PRESONUS ADL 600 (tube preamp)

[Anderton]

PreSonus ADL 600 – Prologue

When I did a Pro Review of the Mackie Onyx 400F, I thought it wouldn't last more than a week or two…after all, what can you say about an audio interface for a computer?

Well, it turned out there's a lot you can say about an audio interface. And in the case of this Pro Review of the PreSonus ADL 600 (a collaborative effort with Anthony DeMaria Labs), I suspect we'll have a lot to talk about as well. What makes a preamp worth $2,295.95? One of the purposes of this review is to find out if the price tag is justified, and if it is, what that buys you.

But what’s also going to make things really interesting is that this is a preamp intended to have "character." It's not supposed to be a straight wire with gain, but a straight wire with attitude. That’s just begging for controversy right there, but the ADL pedigree says a lot, and PreSonus has gotten to where it is by picking and choosing its products carefully.

Another point worth considering is that I've never been a "my slew rate can beat your slew rate," boutique kinda guy. I have my preferences, but if what comes out of a preamp is suitably close to what came in, I'm happy. So part of my interest in getting "up close and personal" with the ADL 600 is to find out exactly what a pricey puppy can do for my sound.

As with other Pro Reviews, I see no point in restating material that's available elsewhere. If you want specs, a block diagram, applications, and the like, PreSonus has quite a complete "product landing page" for the ADL600 at http://www.presonus.com/adl600.html. You might want to swing by there for a bit and get some background before getting into the review. To see what the ADL 600 looks like, click on the attachment to view the front panel. To get an idea of what it feels like, get a bunch of telephone books and some bricks – it weighs in at a hefty 28 pounds.

For those of you not familiar with how the Pro Review concept works, it's simple: This is a forum, so everyone's invited to participate in this "open source" review. If you have questions, comments, or concerns, step right up and voice them. As usual I’ve also invited PreSonus to participate, and I’m sure they’ll be more than happy to talk about the fine points of vacuum tube design, or whatever else strikes your fancy. Please note that this is a sponsored review; for details on what that means, click here (http://acapella.harmony-central.com/forums/showthread.php?s=&threadid=1070486) for the Pro Review FAQ, as well as links to other Pro Reviews.

Okay, that’s enough blather for now. Let’s open up the box, and get started.

[Anderton]

The ADL 600 has rear panel XLR connectors for line in, mic in, and line out. Click on the attachment for a view of the rear panel. I would like to have seen a combo jack for the line ins so you could feed in 1/4" phone jacks without adapters; I assume PreSonus would say that XLR-only jacks are sturdier. I’ll ask when a company representative checks in.

1/4" input phone jacks are on the front for instruments, along with a switch to select among the various ins (note the four different impedance options for the mic in; more on this later). While you can't mix different ins together, note that the two channels are completely independent so you could, for example, use one channel for mic and one for guitar. Speaking of guitar, the input impedance for the instrument input is 100kohms; I would prefer to see that doubled to avoid any chance of loading with passive, single-coil guitar pickups. However, 100k is considered an acceptable value for high-impedance guitar inputs, as evidenced by the many effects that use this value.

On the right channel, the +48V phantom power switch (and it really is +48V) is located between the Power and Polarity switches. This makes unlikely that you’d hit it by accident, as you won't be flipping these other switches much. For the left channel, the phantom power switch is located between the instrument input and polarity switch - again, the odds of hitting it accidentally are remote.

There are also filters, gain controls, and so on, but we'll get into those as we delve into real-world applications. In fact, as one of the ideas behind a Pro Review is to evaluate a product in context, I'd like to speak a bit about that context.

One of the reasons I'm starting the Pro Review now is because I have several NAMM videos to complete for the HC NAMM report. I’m doing these last because they all require narration, so it seems like a perfect chance to put the ADL 600 through its paces. I'm also working on some library music, which requires guitar, synth, and drum machine parts. This gives a good chance to check out the instrument preamp, as well as what kind of "character" the line ins add to various electronic instruments.

I'll also be doing some miking with the ADL 600 at Maricam studios in Santa Fe, which specializes in recording classical and acoustic music, as well as recording some percussion and other sounds in my own studio. Finally, I'll use the ADL 600 in mastering applications to see if there's any real advantage to adding a "tube sound" to certain types of material.

Along the way I'll comment on the build quality, ease of use, documentation, and whatever else seems worthy of note – or more importantly, whatever you ask about! Meanwhile, it's getting late…rather than start doing narration now when my voice is shot, we'll revisit this in the morning. See you tomorrow.

[bluesway]

i'm glad you did this review, since i've been a lover of PreSonus for years and when they came out with (correct me if i'm wrong here) their first BIG TICKET item, i was curious to see how good it was going to be. i currently record with a PreSonus Firepod and i love it, but my preamp is an Avalon 737. (amazing) how would you say it holds up in comparison?

[Anderton]

Well the Avalon stuff is great, but I don't have one here for a direct comparison. I'm going to be dealing with the ADL 600 on its own merits, and try to describe what it does as accurately as possible...hopefully that will be enough that you'll know what to expect, and how it differs from other units out there.

I will say my initial impressions are very favorable...three tubes, high voltage, and an output transformer (a very important element IMHO) do make a difference.

[zax2]

Craig,

I am so glad to see you reviewing this fine preamp. I just got one a week or so ago and am taking it through its paces during some tracking sessions and have been amazed so far by the results.

While every preamp has its own sonic "fingerprint", the ADL 600 has really blown me away so far.

Looking foward to experiencing this unit along with you.

Neil

[Anderton]

Okay, testing time. I’d written the script for the IK Multimedia video, and it was time for narration. I chose a Shure SM58 dynamic mic because I know it better than any other, and plugged it into the ADL 600 input. I plugged the output into my Panasonic DA7 mixer, which has quality preamps that I thought would provide a good standard of comparison – again, I know them well. I didn’t have an A-B switch per se, so I dedicated one input to the ADL 600 out, and another to the straight mic in, and spent a lot of time patching between the two of them for comparison.

Click on the attachment to see a close-up of the controls we’re about to cover.

There’s a “master” gain control with eight stepped settings in 5dB increments, from 35 to 65dB of gain. I was pleasantly surprised that turning it didn’t produce any pops. An additional Trim control alters the gain plus or minus 10dB. I was also pleasantly surprised by the lack of noise; I expect some degree of hiss out of tubes (especially three of them), but the ADL 600 seemed quieter than average.

As the input switch has four choices of impedance, I figured I’d explore that first. Choices are 150, 300, 900, and 1500 Ohms. There’s no “right” setting; it depends on which you like best. The most dramatic difference was between the 150 Ohm setting and everything else: It had slightly less output and low end. This isn’t necessarily a bad thing – if you’re close-miking and doing the proximity effect thang, this might be the best option. However, I was keeping the mic several inches from my mouth, and wanted more of an intimate, “FM DJ” sound. I was drawn to the 1500 Ohm setting, which gave a really full, round bottom. But after a while it seemed a little exaggerated, so I dialed in the 900 Ohm setting and it seemed perfect for the task at hand.

The best way I found to test out the positions was to sing a constant, fairly low note and turn the input knob. The difference among positions is subtle – any changes don’t hit you over the head – but I can’t imagine anyone not being able to discern a difference.

The input knob was a little loose, but the ADL 600 comes with a Allen wrench for the knob setscrews, so I tightened it up. (It makes me wonder if they loosened that knob on purpose just before shipping so I’d appreciate the inclusion of the Allen wrench!)

Having gotten the low end the way I wanted, I started to mess with the HP filter. There’s a switch to bypass it, and a three-position frequency switch: 40, 80, and 120Hz. The response is gentle (the specs quote response as being 12dB down at the selected frequency) so if you have some serious low end problems, you’ll likely need to take care of that in your host, or with a different processor. It’s definitely not a digital brickwall filter. Having said that, though, it’s effective. Engaging a response drop at 40Hz “tightened” the vocal sound, while the 120Hz position definitely started affecting the vocal range. Hmmm…so what happens if you use the HP filter and the input selector together?

[Anderton]

Hey Neal, welcome aboard. One advantage of Pro Reviews is they get people to post who otherwise just lurk :)

However, you're not getting off that easy! Could you let us know a bit about how you're using it -- what are you miking, where do you think it works best, what exactly about it blows you away -- that sort of thing. The more opinions are expressed here, the more effective and helpful the review.

[Anderton]

As I said at the outset, I’m not a boutique kinda guy. But I am a tweaker and a perfectionist, so I couldn’t resist seeing how the HP filter and input impedance selector interact. And actually, they do interact quite a bit, thus allowing more tailoring of the mic sound than either option allows by itself.

I need to emphasize that again, these are subtle differences. For example, popping in the 80Hz filter with the 1500Ohm position tamed the low end compared to just using the 1500Ohm setting by itself, but the sound was different compared to just the 900 or 300Ohm settings, which also tamed the low end – but in a different way.

At this point, it would be logical to say “But why don’t you just use EQ in your host program to dial in the changes you like?” And yes, you could create a similar effect solely with EQ. But again, there are subtleties to consider. Of course, a passive filter sounds different compared to a digital filter. But perhaps of greater importance is that your choices are limited and repeatable. In other words, if you find that a particular input impedance and filter setting works well with a particular mic for narration, well, it’s easy to dial in the next time. Of course you can save presets with plug-ins, but there’s always an immediacy about flicking a switch.

Another point is that by making these changes in the “front end,” you’re influencing the recording process. Cutting out bass rumble before hitting your recorder means you can get more level into the input, as opposed to recording a signal with rumble and then trying to get rid of the rumble at a later time, like while mixing. It’s also worth considering that the interaction between mic and input with respect to impedance is a complex one with many variables; I think it will be quite some time before we see an “impedance matching modeler” plug-in. Yet this does make a significant difference to the overall sound.

I was a little surprised to find myself paying such close attention to these minutiae, but hey, they’re built in to the unit and I’m doing a Pro Review, so I gotta check it all out. You can definitely get hung up seeing how close you can dial the sound in to perfection, but frankly, the results were worth it. I felt I found a combination of settings that provided a good match for the mic, and flattered my voice.

Now it’s time to concentrate on trying to define the ADL 600’s “character,” because it does have one.

[Anderton]

So how does it compare to using the plain, yet very competent, DA7 preamps? Unfortunately attachments with this forum software are limited to slightly over 100k, which precludes providing WAV or AIFF samples of any reasonable length. But actually, it’s not too hard to describe the difference.

The most noticeable difference is that the high end has a bit of a “sparkle.” It’s a certain clarity that isn’t strident or bright, but does add definition. I’m not sure what specific aspect of the circuitry accounts for this (any PreSonus people out there who can answer this?), but I think that using a higher impedance setting at the input selector might account for at least part of the clarity. As a dynamic mic is an inductor, and high frequencies are loaded down more by lower impedances than lower frequencies, this doesn’t seem like an unreasonable assumption.

The next most noticeable difference is a slight sort of compression. Yeah, I’m going to use the term “subtle” again. I can’t tell if this is solely an amplitude-related phenomenon, or if perhaps there’s a very slight bit of overdrive short of distortion; in any event, I felt it added a bit more intimacy to my voice.

Another slight difference is a sort of “creaminess” or “thickness” in the midrange. I’ve often heard this effect in gear with quality output transformers, so presumably that’s the factor at play here; the ADL 600 has an output transformer driven by a tube output stage. Another interesting aspect is that the vocal sound through the ADL 600 is (and I hate to use this word) is more organic-sounding. The DA7 preamps sound accurate, but the ADL 600 kind of coats the signal with a certain veneer of richness.

Just to see if this was psychological, I recorded a little bit of vocals through the ADL 600 and through the DA7 pres. On playback, there was a definite difference. Although I couldn’t exactly do a double-blind test, nor could I maintain a totally consistent vocal quality at exactly the same level, I think that given a sufficiently consistent vocal sample of sufficient length, it would be easy to identify the two preamps in a listening test.

Bottom line is that I feel my narration vocal quality was considerably improved compared to the DA7 pres; as a “real world” reality test I also tried the preamps in the Digidesign Mbox2 and PreSonus FireBox. Again, there was a definite difference when using the ADL 600; the sound was rounder, more defined, and more intimate.

It will be interesting to see if these differences hold up after the video goes through the mixing and encoding process. There are two NAMM videos posted on this site using other preamps, so I’ll be able to compare them to the newer videos that use the ADL 600. My initial reaction is that the degradation in quality caused by the data compression process will mask any differences, but we’ll see.

It’s dinner time now, and I doubt I’ll get the video finished tonight…but I might. In any event, when I do, I’ll move on to the next part of this Pro Review: The instrument input. If this holds up next to my big-bucks Class A DI box by Radial Engineering, I’ll be pretty impressed.

[Warhead]

Hey Craig, I was present at one of the shootouts the studio next door to us was doing to write their upcoming ADL600 review in EQ Magazine. I also have a fair amount of time using the pre myself, and I'm curious to see your findings!

War

[diamondjim]

This is great timing... I just got my ADL 600 last week and started some recording tests this weekend. I agree with your assessment of the "creaminess". That was how I described the sound of my violin and acoustic guitar recorded thru Earthworks TC-20 omnis. When I record through these direct to the FF800, the sound is very clean and detailed, but without added character, which is fine in some cases. However I got this unit to counteract the impression some clients have of digital being too sterile. Actually I think that some people can't stand the actual sound of their instruments, but that is another debate.....

In any case I was amazed at the difference in sound, definitely a richer sound, like the difference between black coffee and a mocha latte!

OK, now I need to go back and try some other mics and the direct input. I have a collection of decent but lower end condensors, Marshall and Octava, which I am hoping this unit will make even better sounding. My fav mic is the Marshall V69 tube, so it will be interesting to see if the ADL 600 improves that already great sound.

Thanks for starting this thread, Craig, I was really looking for some seasoned input on this unit, after dropping $1800 (Sweetwater B-Stock, great deal!). I am looking forward to hearing more of your opinion.

[Anderton]

<<I also have a fair amount of time using the pre myself...>>

So, whaddya think? How do you use it? And tips or tricks?

[Magpel]

I'm certainly not in the market for any big ticket pres at the moment, but I thought I'd drop in to say that Anthony DeMaria is an old friend of mine from grade school, that he still lives around the corner from me, that his nickname is D-Mo, and that he's a really good guy who loves his work...so, uh, buy this unit!

I do have some experience with his gear. He left a prootype of his single channel comrpessor in my wee little composing studio for the better part of two years, even though he knew its price was way out of proportion with the economics of my studio.

...But in the 8th grade one-on-one basketball tournament, D-Mo beat me in the finals when the gym teachersrefused to call him for clearing me out, again and again, with his left arm as he drove to the basket...

carry on :freak:

[Anderton]

Interesting side comment! I must say the unit has the "vibe" of someone who was designing the unit for himself, not for a focus group. There's a lot of "spare no expense" stuff going on, like the component quality, that probably wouldn't make it through a team of accountants but easily passes muster with engineers.

I don't know how much I'll get done today, I haven't had the chance to try anything new...still doing narration. But the one thing I will say is that my initial impressions are holding up.

[Warhead]

Originally posted by Anderton
<<I also have a fair amount of time using the pre myself...>>

So, whaddya think? How do you use it? And tips or tricks?

It's HUGE sounding is my main thought when using this preamp. It's not just the low end that sounds large and extended, it has a big presence to it from top to bottom. It's also very quiet, as quiet as most solid state stuff really. Another standout feature of this tube pre is the detail, there is great detail going on that is not normally associated with tube equipment and transformer in and out preamps.

As an example, when used on overheads against several other high end preamps (KM100 mono setup) the ADL600 was the only preamp where a kick mic might have been optional. The low end was just there, pulled to the surface and present. On kick drum it was insane how much of EVERYTHING it delivered top to bottom, and I've talked to several other guys who are now using it as the go to kick pre.

My only tip thus far would be to use the ADL600 when you need a huge track like vocals, kick, maybe a featured guitar etc. When mixing it's impossible to make everything sound large so for guys with multiple preamp setups this preamp will come in quite handy for featured tracks that need that size.

War

[zax2]

Craig,

As always, you are amazing in your details and perception.

As soon as I got the ADL into the studio, I thought I would do a little shootout with some of the other mic pres that are here and I have been using on different projects. The culprits for the test were obviously the Presonus ADL, a Universal Audio LA-610 (a longtime favorite of mine since I got it), my trusty Peavey VMP-2, and a Focusright Vocal Master.

I had a singer friend of mine come into the studio and do some singing with the constant of each test being either a Blue Blueberry mic or a Studio Projects C1. I thought that might be a great cross section of microphones for my use.

An added piece of gear for the testing was a Peavey VC/L-2 tube compressor. These compressors really are great and it is ironic it even has the Peavey logo on it (as many of you know might know). This is a classic case of not judging the book by it's cover.

The first thing we noticed about the ADL was the high headroom it afforded. The sound was big, natural, and warm. The highest compliment that I can give it was that it was extremely transparent in allowing the natural sound of the mic and singer come through, but adding a character of it's own (this is not a bad thing). It sounded REAL.

The LA-610 (with no compression) sounded great as well, but it was a different "fingerprint". It was not as open and wide as the ADL. The Peavey fared well, but there was a mid hump in the tone that unless comparing it to the ADL you would never notice. The Focusright was taken out of the test immediately as it sounded like a piece of paper compared to the ADL.

One thing I might mention is that the dual metering (LED as well as VU) is extremely cool and useful.

To boil down the results, our favorite preamp (in blind listening tests) was the Presonus hands down. The mic of choice for that test was the Blueberry. :thu:

The one thing that is a bit esoteric, but worth mentioning is that I think is that the ADL has a certain "vibe" to it. Just taking it out of the box and racking it you can feel the incredible build quality, attention to detail, and solid components (knobs don't wiggle, switches are solid). It just feels strong and dominant.

After plugging in and taking it through it's paces, I have just started recutting some tracks I am doing for my next CD so that they will be recut through the Presonus. THAT'S how impressed I was with the sound.

I will be tracking a variety of instruments over the coming weeks and I will let everyone know the results. Coming this weekend, Hammond B3...


Neil

[ricknaqvi]

The most noticeable difference is that the high end has a bit of a “sparkle.” It’s a certain clarity that isn’t strident or bright, but does add definition. I’m not sure what specific aspect of the circuitry accounts for this (any PreSonus people out there who can answer this?),

Hi Craig and folks,

The 'sparkle' is due to a couple of factors. First, the ADL600 is running at a very high plate voltage which also gives it a lot of headroom. This in combination with a high slew rate and low noise helps to bring out more definition in the upper mids and high frequencies. The type of input and output transformers also contribute to the way that it sounds.

Hope this helps.

Regards,

[Anderton]

<<It's HUGE sounding is my main thought when using this preamp. It's not just the low end that sounds large and extended, it has a big presence to it from top to bottom. It's also very quiet, as quiet as most solid state stuff really. Another standout feature of this tube pre is the detail, there is great detail going on that is not normally associated with tube equipment and transformer in and out preamps.>>

Interesting we're picking up on the same things. I do feel some of the "largeness" is due to the impedance matching options. The "detail" is harder to pin down, the "miller effect" in tubes has a tendency to dull highs a bit...I think that may be one reason why people dig 'em for guitar amps. Yet the high end seems really sweet, which I didn't expect.

I'm hoping someone from PreSonus can come in here and explain some of the circuitry behind these characteristics, unless of course it's proprietary or something...I guess my point is we all HEAR there's some mojo going on, but I'm curious as to the technology behind what we're hearing. It can't just be good quality parts <G> -- or can it? Do quality capacitors REALLY make that much difference?

[D Charles]

Hi Craig,

Several years ago I bought an expensive tube pre made by Avalon. We almost sent it back because just listening to soloed parts, it wasn't a world of difference from my Mackie and Hill mixers and some low cost pre's we had around.

THEN we tracked some multiple parts of the same thing and played them back together. WOW, there's the real difference in the high ticket stuff and the consumer stuff. Everything seemed to have it's own 3D space and it was way way easier to mix the parts.

The biggest difference I noticed was on background vocals (they had no build up of crunchy consonants or excessive sibilants like with the cheap pres), bass and acoutic instruments. Even if I were rich and could afford a different pre for every instrument or voice I record, I'd keep the Avalon around just for backup vox and bass guitar.

I think you should try some multiples of the same part with the PreSonus. A high, mid and low harmony vocal part would be really telling in how well the parts blend and how easy they are to place in your mix.

I think the 'one or two channels of an expensive mixing desk' items were made for people like me who mostly track one part at a time.

[Anderton]

<<THEN we tracked some multiple parts of the same thing and played them back together. WOW, there's the real difference in the high ticket stuff and the consumer stuff. Everything seemed to have it's own 3D space and it was way way easier to mix the parts.>>

That's an excellent point -- CUMULATIVE differences. It's like if you shave 1 dB of noise off of a 24-track mix, all of a sudden you have a lot less noise. I plan to try what you're talking about with guitars, so far the guitar sounds I'm getting are pretty righteous!!

[UstadKhanAli]

That's a really great point about the cumulative effects of mic preamps (and the same goes for converters). You can really spot the idiosyncracies of these when you start layering things are using them for entire recording sessions. Great aspects, anomalies, not-so-great aspects can really come to the fore after doing this.

[gsbe]

I really like the way this type of product review works. I look forward to reading more of this one and other in the future. Hopefully this type of idea will catch on in MI reporting. It would be great to hear the comparisons you're creating, also. Perhaps you could just host them at h-c.com and post links to the files. Anyway, just wanted to give you some quick feedback to say that this is a great method for product review.

[roguescout]

I just want to know who won the ADL 600 Giveaway!

Two detailed emails to Presonus regarding this resulted in no answers and I can't find any link to the info on their site.

Does anyone know how this turned out? Obviously it wasn't me. But I believe it is illegal to conduct a contest and not produce the results.

Thanks for any info you can provide!

[Anderton]

<<I really like the way this type of product review works. I look forward to reading more of this one and other in the future.>>

There will be many more to come. You might also want to check out the ones that have been done already, there's a stricky thread here with links. Thanks for the feedback!

[Anderton]

Just saw the ADL 600 banner ad. Guess the people at PreSonus have noticed what's happening, eh? Now maybe one of them could check in and answer some of my questions...

I used the ADL 600 for narration all day and yeah, it DID sound really good. Even after being data compressed mercilessly, it STILL sounded bigger & better. When the Edirol, Boss, IK Multimedia, and Roland videos get posted, I bet you'll hear a difference compared to the videos I did without the ADL 600.

Next up is guitars............

[modul8]

First I would like to say this form of review is a brilliant concept. We gain the benefit of a blow-by-blow shake down of a new piece of gear from the vantage point of one of the most respected industry writers in the world along with the added input of other active users in one convenient location. Gone are the days of searching for reviews and then a separate process of weeding through the host boards :-) (well... perhaps eventually)

Craig, I have always wanted to thank you for the work you do. Your various magazine columns and reviews have been a great value to me over the years. Pointing me in new directions when I was lost as well as reinforcing my own discoveries and conclusions giving confidence in my approach to making music. At some point I became aware that you literally wrote the book on a large portion of the gear I rely on daily (Emax, EmaxII, SP1200...). I truly respect your opinion and value that you often express a budget conscious approach to quality production.

I am very excited about following the progress of this review. The ADL is definitely an exciting introduction. I look forward to your progress!

Now... why don't I email Universal Audio about a high quality UAD-1 Quadrafuzz... ;-)

[Anderton]

<<Now... why don't I email Universal Audio about a high quality UAD-1 Quadrafuzz...>>

You have no idea how close you are to reality with that statement! I don't want to get off topic, but...stay tuned.

[modul8]

I will be here DAILY!!!

Quadrafuzz was my favorite plug-in back in the VST-24 days. Saddly, I gave up on Cubase some time ago but always missed my quadrafuzz. The sounds you can create are truly inspiring (I favor the dark side of electronic music)!!!

Automatable everything would be nice :-)

Back to the topic at hand, I am very interested in how the ADL handles male, baritone vocals and analog synth (bass in particular). Has anyone had the oportunity to use the ADL with these sources? What are your impressions?

[Chrismeraz]

Roguescout,
I'm with ya, who did win that darn drawing?? I guess we're all just "mad it wasn't me."

Seriously though, I can't wait to hear some comparisons from Craig (not to rush you buddy). Here's what I'm looking for:

I have a Digi002. Preamps are fine, no complaints. My only mic is a Mojave MA-200, I use it mostly for vocals and classical guitar. Would the ADL really make a $2000 difference? Would it even make a $1000 difference? I think I would be better off spending that money elsewhere (another microphone maybe). I can't imagine a preamp making so much difference. This is probably an item to consider for big-budget studios, but not really for us little guys, isn't it?

[diamondjim]

We just finished tracking an acoustic guitar with vocals through the ADL 600. The singer has been looking for "that sound" for some time, and we came close with the Marshal V69 on vocals, but when adding the ADL 600 up front, and running the guitar through an Earthworks TC-20 omni condensor, the sound was stunning! Very full and clear. It sounds as good raw as any track I have ever mastered, and this one has no treatment whatsoever.

Needless to say I am keeping this unit, and my wife now feels better about the money spent on that "warmer upper thingey". :love:

[benpasley]

Guys, great forum! I have been a Presonus user for quite some time, and I was very pleased to score one early to use in a preamp shootout back in the fall 0f 2005, and then I bought it! By the way, I am very utilitarian, not rich, and if I buy an expensive piece of gear it has to seriously contribute to the core of my work as a producer/artist.

I had some great companies like Front End Audio and Mercenary help me with preamps for testing, along with Rick Naqvi from Presonus. I tested the Langevin Dual Vocal, Presonus ADL, Great River MP-2, and Phoenix DRS-2. A lot of variety here, but excellent all, and I wanted to invest in a few channels of "work specific" preamps to help my productions move to the next level...after hearing them for myself. For clarity on "work specific": I record a lot of vocals, acoustic guitars, and deep and dynamically challenging world drums. I also record electric guitar and kits, but they are not central to my work.

In summary: I though each pre had an excellent place in studio applications. For my work the transformer-thick Great River and Phoenix pieces were a bit too colored through the midrange for my multi-purpose preamp goals. I chose the ADL hands down as the best all purpose pre of the bunch. It was extremely responsive to the dynamic content (even with a mild tubey compression at higher gain settings) and really allowed a wide variety of instruments to live in a very 3-dimensional space. It was also so absurdly quiet I couldn't believe it was tubulated. The velvety sheen it imparts to material which is intensified at high gain settings is very musical, not hyped, and extremely desirable on vocals and melodic instruments. At low gain settings it was suprisingly articulate even on the challeging percussion-meets-tone of the acoustic guitar--unlike any tube pre I had ever heard.

As a note, I also bought a used Langevin Vocal Combo--not for vocals--but because the depth and impact of the low end on the Langevin piece was incredible, fast, and extended. I believe that for better low end impact that the fast, tight Langevin is better on kick and djembe, etc. though I do understand that some people like the kick to be harmonically enriched and not necessarily extended into the below 50Hz range...I did use the ADL on kick and snare in a progressive rock session in the fall and the results were awesome. In hindsight, after listening to the recording, next time I would use the ADL on overhead/stereo room mics and the Langevin on the up close mics because what the ADL does to "sexify" the sound would be best used in my 3 to 5 drum mic preference (jazz/natural) as the primary sound of the kit in the room.

Yesterday, I wrapped a three day recording session with a singer-songwriter working on Chair and Microphone, Volume 2 which is a stripped down, natural sounding record featuring guitar and solo vocal only--recorded in one pass, no overdubs, four mics. I set a tube mic and a 4050 to figure-8 pattern for near miking the vocal and guitar, respectively, (great off-axis rejection in those patterns) and I set two 4047's at wide stereo position for capturing the big, wooden retreat lodge we tracked in. I used the ADL on the near mics and the sound was freaking amazing. Because the ADL is so "lively" I decided to apply compression using a cheap but very handy ART Pro VLA which is a slow opto-compressor (very sparingly), but the combination allowed for lots of breathing room without fear of killing the inputs when Aaron Strumpel, the artist, went from whisper to scream. I drove the ADL pretty hard on the vocals, which in my experience means if you push over the midway point on the LED metering you are into the "thickening" tube saturation, and I kept the kept the guitar gain way down so the meters moved barely beyond 25%. The ADL is so quiet you can get away with this kind of setting, and the articulation and clarity is greatly increased at low input levels. This recording is the best stripped down thing I have ever done, and most of the credit goes to the ADL-600 for giving me what I have never really had--an esoterically beautiful sounding preamp--it really has made my modest microphone cabinet sound like a million bucks. I will use very little EQ or post-mods on this recording and it will be out in about 60 days.

I look forward to providing any feedback you folks in the forum might have...happy recording!

Ben Pasley

[Anderton]

Wow, these are some fantastic comments, very useful and educational. Thanks for contributing to the thread, it's giving me a chance to dig in a little further on my own without feeling like I HAVE to post something.

That's one thing I really like about this review format -- it develops its own personality and can unfold over time. Sort of like peeling off the layers of the onion :)

[benpasley]

I am glad my last post was helpful. I don't want to crash in here with too much info, but I did notice someone was curious about ADL-600 over the mix bus...

During the aforementioned "preamp shoot out" I was weighing the investment/return ratio on spending money on an analog summing bus or other neato-magic-analog gear that might impart some textures to my DAW output. I use DP and the Motu 828 Firewire I/O for recording to final product. With that in mind I decided to put the ADL-600 across the stereo bus. For caveman testing I even put a Presonus M-80 across all 8 Motu outputs (stemmed mix) just to listen for actual analog summing effect even though this unit was not specifically designed for that application. I pulled up some southern roots-rock mixes I had on the hard drive that had lots of bam, biff, and sock...and I was familiar with the mix and mastering that I had done earlier.

My impressions: My ears did not hear any significant contribution to the final audio via either of these analog experiments that would assist me, under normal conditions, in mix/mastering. The M-80 did nothing really that I could tell that could be called magical. The ADL did impart a noticable thickening of the midrange sound as you would expect and some softening of the peaks...the more you pushed it, the more of this effect you could acheive. It was definitely quiet enough for this application, and it also has well put together balanced XLR line inputs on the back to make it easy. I though it might be cool on some very unique mixes, though I can't think of what they might be, but probably best used to "reamp" a signal like a dry keyboard input or a flat bass guitar track to impart the much desired harmonic textures.

Bottom line: I have banned personal thoughts about analog summing altogether since that experiment, and I chose to go the route of spending money on excellent preamps for the front end. So, at risk of sounding like a salesman: go buy an ADL-600 for your "go to" mic preamp!

(Bonus note: For those of you on extremely tight budgets, like me, I have found the single most magical piece of gear across a stereo bus at mixdown is the $400 ART Pro VLA. Run with the lowest compression ratio, fast attack and release, with almost no visible impression on the meters at all...that thing makes flat tracks really come alive and gives digital mixes a sizable boost in the width of stereo image, shape of instruments, and girth in bass content...for what it's worth.)

Ben Pasley

[zax2]

This weekend I was supposed to track B3, but I ended up recording guitars and here is my experience.

For a majority of my recording these days, I "reamp" direct guitar tracks to regular amps during the mixdown process. Without going into the pros and cons of this, it really has its advantages because I can always change or tweak the sound later.

In any case, I have been using Guitar Rig 2 a lot lately and really loving it. Normally, my guitar would go into the first mic pre on my Digi 002R in GR2 and that would be the end of it. I never needed or wanted "tube tone". I just wanted a dry guitar ready for reamping later.

Today, I ran my guitar into the ADl (instrument input) and then into the 002. What a difference! Obviously, the mic pres in a 002 can never compare to something along the lines of the ADL, but the difference was amazing. The sound was bigger, yet more defined as I would A/B different presets.

All the bells and whistles were off. No HP filter...

I was just amazed that the ADL made the sound right off the pickups sonically more pleasing.

Thankfully, I caught this way of tracking guitars before I got too far. When I eventually reamp them at mixdown (if I even do as the tone I am getting is killer) I will report that as well.

More to come...

Neil

[ricknaqvi]

I just want to know who won the ADL 600 Giveaway!

Hi CHRISMERAZ and ROGUESCOUT,

The winner of the ADL600 was Charlie Woolford who lives in Kansas. We actually did the drawing but were delayed in posting the results due to the NAMM show which fell at the end of January. Sorry for confusion.

Here's the link on our site: http://www.presonus.com/contestwinners.html


Kind Regards,

[Anderton]

Welcome Rick, good to see you here checking up on your "baby." It's doing a great job in the studio here...let's see, how long can I stretch out this review...let me look at my list of upcoming projects :)

Seriously, one thing I want to talk about some more is the build quality. I assume you won't mind if I take it apart so I can take some close-up photos, right?

[ricknaqvi]

No problem Craig. Feel free to take it apart.

BTW, (I assume you know this but) just be careful because the powersupply still holds current after the unit is turned off. I'd hate to taint your opinion of 'high voltage' mic preamps so soon!! :-)

Cheers,

[drummin4christ]

Thanks Craig for starting a great review!!!

I have been using the ADL600 for about 4-5 months now. I have been very impressed with the amount of detail this unit protrays. The depth of lowend is very impressive and this has become my goto mic pre for kick. I am also in the middle of tracking vocals on a project and the tracks have turned out very warm, detailed, and present. Sonicly, this unit completely delivers!!! This has been a great complement to my API 3124+.

I have also been very impressed with the detail of the acoustic guitar tracks I've recorded. It sounds like I'm sitting in the room with the guitar. I absolutly love it!!!

[Anderton]

Today I cut vocals for a tune where the recording process had been interrupted by NAMM. I had already cut one vocal prior to opening up the ADL 600, so I used the ADL to double-track a backing vocal. I was curious how the two would mesh.

The ADL 600 ended up having a more "dominant" sound, which was not my intention. I tried to tame it a bit in the mix by reducing the level somewhat, and rolling off some highs. But then it just sounded like a lower-level vocal with less highs :) That wasn't my intention either!

I decided why fight it. The ADL 600 vocal sounded better as the lead vocal, and the original vocal sounded better as a backing vocal. Unfortunately, though, the performance of the backing vocal was better. As I had a lot of other Harmony Central things to do today, I put doing a finished vocal on the back burner. But when a few minutes open up, I'll re-record the lead vocal through the ADL 600 until I get a better performance.

However, I will keep the other vocal as the second backing vocal, and not re-record it through the ADL 600. This is a useful lesson about when and when not to use "character" in a preamp; the background vocal seems to work better when it has a "flatter" character, as it doesn't draw attention away from the lead. Perhaps I could tweak the ADL 600 controls to give a flatter, more neutral sound; I'll have to try that at some point. I've been sorta seduced by the sound I get from pushing it a bit, but in the interest of completeness, I also need to try out some more conservative settings.

So now I'm starting to see the ADL 600 as not just a preamp, but as something to pull out when a track needs a little more emphasis or character. It's different from boosting the level or changing the EQ; it can add a certain "vibe" to a track and by doing so, lets you have a little more control over the soundstage, and provide a bit of a variation compared to other tracks. To be fair, this is not unique to the ADL 600; different preamps do sound different. I've found, though, that the ADL 600 has a broad pallette of sounds, so it's much more than a "one-trick pony."

Bottom line: Choose the right tool for the right job. The background vocal definitely worked better when it sat back in the track, and the lead vocal definitely worked better through the ADL 600.

[D Charles]

Cool observations. I read an article about a producer who said he mostly used Neve channels for lead vocal and Avalons for backups. I can see how different textures could blend well.

Another thing I wish you'd try (time permitting) is to run some stereo synths and drum machines through that ADL to recorder and see if they sound bigger or more life like.

Thanks!

:thu:

[Anderton]

<<Another thing I wish you'd try (time permitting) is to run some stereo synths and drum machines through that ADL to recorder and see if they sound bigger or more life like. >>

Absolutely! I've pretty much found out all I need to know about vocals. Guitars are next, then synths and such. I've also booked some time at Maricam studios to check out acoustic guitar.

[dr_chopz]

Hey Guys,
Couldn't take it any longer... ordered a 'B' stock from Sweetwater! Can't wait!

Craig, cool format for the review... appreciating your comments as well as hearing what other folks are up to. Wondering if Anthony DeMaria would like to offer his "input" as well... maybe hear how the prototype evolved into its present incarnation... using different tubes (what type are in there now?), getting his side of the story shooting hoops with magpel. :D Anyway, always cool to hear what the designers have to say.
Thanx,
Torry

[Magpel]

Originally posted by dr_chopz
Wondering if Anthony DeMaria would like to offer his "input" as well... getting his side of the story shooting hoops with magpel. :D Anyway, always cool to hear what the designers have to say.
Thanx,
Torry

lol. I wonder if Anthony would even remember that. He wouldn't recognize me by the name "Magpel,"but the bit about him leaving one of his mono compressors in my humble composer's studio for 2 years would be the giveaway.

[Circulogi]

Craig,
Great review. I had an oppurunity to check one out about a month ago and was quite pleased with it. For those of you paying $1800 at Sweetwater for B-stock, check around. You can pick them up new for a bit less than that. :)

[diamondjim]

zZounds - $1999.99
digitalproaudio - $1999.99
Dale Proaudioshop - $1999.99
Sam Ash $1995.95
ProAudioAmerica $1999.99
BSW $1995.00
musiciansfriend $1999.99
americanmusicalsupply $1999.99
samedaymusic $1999.99
musiciansbuy $1999.95
amazon $1995.95
nothing on eBay

OK, I give up! Where?

My sweetwater B-Stock item was essentially new. A single 1/2" scratch on the top, probably from when it was first removed from the box. Everything else perfect, original shipping carton, the works. $1800 was a sweet deal for this!

[Circulogi]

I just did a Google search and Front End Audio has a demo for $1699. I know for fact that other dealers who I also found on that same Google search sell news ones for less than that. Its worth the few seconds to do the search. $1999 is MAP price. I hope no-one pays that. Its essentially retail. Is the ADL600 worth $2000. It actually might be, but if some lemonhead wants to give me deal way below that. I'm gonna take them up on that. :)

[dr_chopz]

Thanx for that demo price Circulogi, but please share thoses other sites with the killer sales price... can't seem to come across any and I've run outta keywords. Just curious. I too searched for months and couldn't find a better deal than Sweetwater's. Front end also has a sale price of $1799... not sure if it's 'B' stock or not.

FWIW, In this case I'd prefer a 'B' stock as they're sent back to the factory and "reconditioned". Initial batches of brand new ADL 600s had a trim pot problem and I wanted to be sure that had been taken care. See link below... be sure to check Chad Kelly's post... Kudos to Presonus for taking care of this in a classy manner btw.

http://gearslutz.com/board/showthread.php3?t=47813&highlight=adl+trim+pots

Torry

[Anderton]

Thanks for the link. It's interesting reading, especially because it pretty much confirms everything I'm saying here. People like this box! As to the trimpot issue, mine hasn't had any problems, so I guess it survived the "UPS shake test."

[Anderton]

Click on the attachment to see a picture of the power supply.

I opened up the box and took a bunch of pictures so you could see the build quality, and get a feel for the kind of components that are used. Here’s the high-voltage power supply, with its warning sticker so that curious people like me don’t have a shocking experience. The main filter caps are rated at 450V; the fuses are top-mounted for easy access – you don’t have to remove the upper power supply board to get at fuses. You can’t see it too easily, but there’s a slot in the metal “cage” protecting the power supply, and the wires pass through a thick grommet on their way to the rest of the circuit.

[Anderton]

Click on the attachment to see a picture of wires connecting the front panel to the main circuit board.

The ADL 600 has connectors everywhee – pots to circuit board, panel board to circuit board, etc. This means that almost all the solder connectors are wave-soldered to the boards, eliminating any possible problems with point-to-point wiring, and also allowing for more automated assembly. The only thing that makes me nervous seeing this many connectors is if you live someplace very humid or very polluted, as the contacts might corrode over time. I think it would probably be good practice to open up the box once a year, unplug the connectors, then plug them back in to wipe the contacts. Does anyone at PreSonus have comments about this?

[Anderton]

Click on the attachment to see a picture of the input transformers.

The input transformers are relatively large and shielded.

[Anderton]

Click on the attachment to see a close-up of the knobs.

It’s too bad a photo can’t convey feel, because these are big, solid suckers. Note the setscrews so you can easily remove or replace them, should it be necessary to service the panel board to which the controls attach.

[Anderton]

Click on the attachment to see a picture of the meter board.

This looks pretty digital to me…I wonder what the “prog” pins are for? I assume the trimpots are for calibration purposes.

[Anderton]

Click on the attachment to see a picture of the output transformers.

The output transformers are slightly larger than the input transformers, and also shielded.

[Anderton]

Click on the attachment to see a picture of the tubes used in the ADL 600.

There are three tubes per channel. The two toward the right are Electro-Harmonix (Sovtek) 6922 types, while the tube toward the left is a Ruby 12AT7. There’s always something cool about a photo with tubes!

[Anderton]

Click on the attachment to see a picture of the rear of the panel-mount XLR connectors.

Even the XLR connectors attach to the main board through connectors, presumably for both reliability and ease of replacement should you smash one by mistake.

[Anderton]

Click on the attachment to see the rear of the ADL 600’s front panel pots.

The pots – well, detented switches, actually – are fairly small. Except for the HP Filter control, they all mount directly to a panel mount board, and wires connect from the panel board to the main circuit board.

[ricknaqvi]

The only thing that makes me nervous seeing this many connectors is if you live someplace very humid or very polluted, as the contacts might corrode over time. I think it would probably be good practice to open up the box once a year, unplug the connectors, then plug them back in to wipe the contacts. Does anyone at PreSonus have comments about this?

Hi Craig,

Actually we have used this type of connector on a few other products in the past and so far we haven't had any problems with corrosion due to humidity. (The fact that we are from Louisiana, the most humid place in the country, gives us a great way to beta test this theory)

However, the only trade off with this type of connector is that if the unit will be jarred around a lot (say in a live sound rack), there is a small possibility of the connector getting loose over time. In a recording studio, you should have no problems with loose connectors.

Cheers,

[MorePaul]

Hey Rick;

You are down in Louisiana?

I believe you did the recording at a wedding I attended a couple of years ago and I had a brief moment to chat with you


I have the CD pressed from that and the sound is very good

[Anderton]

<<However, the only trade off with this type of connector is that if the unit will be jarred around a lot (say in a live sound rack), there is a small possibility of the connector getting loose over time.>>

I see your point, but that might be overly cautious. A lot of the connectors have a little retainer that snaps into a groove on the connector, and holds it in place.

As to beta testing for humidity issues in Louisiana -- yeah! If it's not a problem there, it wouldn't be a problem anywhere...!

[Anderton]

Now it was time to see if I got the same kind of “character” out of direct guitar that I got out of microphones. I compared the ADL 600 with a PreSonus FireBox as the “control,” and also with the Radial JDV MK3 Class-A direct box. For those not familiar with the JDV, it’s the polar opposite of the ADL 600: All solid-state, and transformerless. It’s also been my “go-to” direct box since falling in love with it while reviewing it for EQ magazine.

The first thing I noticed was a very subtle “dulling” of the sound with the ADL 600 compared to both the JDV and surprisingly, the FireBox as well. I checked the specs; the JDV has a 3.9M input impedance, and the FireBox, a 1M input impedance. These are considerably more than the ADL 600’s 100k input impedance, which while acceptable for electric guitar, will produce a subtle shaving off of high frequencies under some circumstances. The dulling effect was slightly more apparent with single coil pickups than humbucker, and with humbuckers, the pickup switching made a difference as well. The effect was much more noticeable with a single treble pickup, and barely noticeable with the bass and treble pickups in parallel.

Now, this isn’t necessarily a bad thing. In fact, the JDV has a “drag” control that lets you dial the input impedance down to 10k ohms – conceptually similar to the ADL 600’s choice of input impedances for matching mics. Some guitarists prefer the “chunkier” sound of a lower input impedance; personally, I like the “crispier” sound of high input impedances. I think it would have been a great addition for the ADL 600 to have a variable impedance option for the instrument input, which would have also been consistent with having that feature for mics. Tubes are inherently high-impedance devices, and the guitar goes into the circuit after the input transformer, so I don’t see any theoretical reason why this wouldn’t be possible.

[Anderton]

If you’re expecting an overdrive device for guitar, the ADL 600 isn’t really set up for that – remember, it has truly massive dynamic range thanks to the high plate voltages, and getting it to overload is not easy. Sure, you can dial in high amounts of gain; but the same high voltage that gives such an open sound with vocals stubbornly refuses to play fuzz tone with guitar. Also note that the output trim control doesn’t really pad things down more than 10dB, so if you do use huge amounts of gain, you’ll probably overload whatever’s after the ADL 600.

However – and this is intriguing – I did notice a definite “opening up” of the sound at higher gain settings, especially with single note leads; the guitar just seemed to “speak” better. When something like that happens, my first thought is "objective testing required." Thinking that perhaps I was being misled by the shifting volume levels, I recorded a couple tracks into Sonar, one with a low amount of gain, and the other with a high amount. I then normalized their peaks, yet there was still a qualitative difference between the two.

Thinking that maybe I’d just recorded a “rogue” peak during the low gain section that didn't let it normalize up to a higher level, I looked for the highest peak, cut that part, then renormalized. There was still an obvious difference. Click on the attachment to see the two waveforms.

You can see that the high gain version has consistently higher peaks and a higher average level. Initially, this seems contradictory: Wouldn’t higher peaks, upon normalization, lead to a lower average level?

I think what’s happening is this: At high gains, the transients are being either soft-clipped by the tubes, “swamped” by the output transformer, or both. Thus, there’s a bit of limiting/compression going on, which accounts for the higher average level. So I wasn’t imagining things: Turning up the gain changed the sound quality, even when matching peaks of the low and high gain sounds, and even though there was no audible distortion.

I guess the bottom line is that when you’re playing guitar through the ADL 600, pump up the gain! Sure, you may need to pad the output a little bit, or turn down the input of subsequent stages, but you’ll definitely get a hotter, more present sound.

[Anderton]

Until I found out the virtues of turning the gain way up, I wasn’t thrilled with the ADL 600’s performance with guitar. It was satisfactory, but nothing mind-blowing. But turning up the gain provides that elusive “character” that seems to be a hallmark of this unit. The difference still isn’t something that hits you over the head, but it’s not subtle either – you can even see it, unmistakably, in the previous post’s screen shot.

It’s also worth noting that the HP filter is very effective with guitar. Setting it to 120Hz can really “tighten up” the sound, and counter-balance the lack of a “crispy” high end. I’d go so far as to say that unless you have a compelling reason not to use the HP switch, check it out with guitar – I bet you’ll find a setting that works better for you than having the HP filter switched out.

Something else I noticed, although this is subtle, is a slightly “rounder” midrange than with the Radial JDV (or the FireBox). I chalk this up to having an inductor in the signal path, which adds a little character (something phasey, maybe?) to the lower midrange.

Incidentally, the ADL 600 is ideal with electric bass. Bass just seems to have a nice, full character through this box. Again, it’s nothing that sounds light years ahead of comparable units; but if you’re in the market for a solid bass and guitar DI as well as a mic pre, the ADL 600 will give you all three, with an emphasis on the mic pre aspects.

Well, I guess I’ve had enough fun for one night :). Tomorrow I’ll start investigating what happens when you put synths through it.

[anthonyadl]

Hi Craig,

This AnthonyDeMaria from ADL. Just wanted to thank you for your time and effort reviewing the new ADL/Presonus pre-amp 600. If anyone has any questions please let me know. Thanks, once again.

Sincerely,

Anthony

[Anderton]

Well Anthony, welcome to the thread! You did good with the ADL 600.

Actually, the only question I have is why you didn't use combi XLR/phone connectors for the line ins and outs. Seems to me a lot of people are using TRS phone jacks, and using combi jacks would make their lives easier.

I'm curious what involvement you've had other than the design. For example, do you do any overseeing of the manufacturing, or is that entirely up to PreSonus? The thing has great build quality...I assume you had some input into that. Inquiring minds want to know! <G>

Thanks again for stopping by.

[dr_chopz]

Originally posted by anthonyadl
Hi Craig,

This AnthonyDeMaria from ADL. Just wanted to thank you for your time and effort reviewing the new ADL/Presonus pre-amp 600. If anyone has any questions please let me know. Thanks, once again.

Sincerely,

Anthony

Hi Anthony, great to have you here! Craig had popped the lid and listed the tubes you've decided to use. Great pics man, and first time I'd seen anyone mention the type of tubes in this baby.

Can you expand on why those selections and possible substitutions (type & brand) that can add different color or easier to saturate/orverdrive. For example, guys were raving about Mullards in various other pres. The ability to add diferent colors is another plus for tube pres.
Thanx,
Torry

[Hype]

Hi Craig, Rick and Anthony.

I've been a longtime Presonus user and actually have a Studio Biography on the Presonus Users page "Brin Addison at Hype Schwartz Productions"

I've been using the ADL for a few weeks now and would like to give you my input.

So far I've testid it on Kick, Snare, Overheads, Bass , Electric Gtr and Vocals. My findings are as follows:
- Kick: sounds great using an Audix D6 thru the ADL 600. I find very little need for compression because the ADL is doing something to the sound that makes it sound "somewhat compressed" in a good way. It just sits in the mix nicely and has great character.

-Snare: Very much the same as the kick with a beautiful sheen and great presence without being bright. Again very little need for compression. I just don't really want to mess with the good sound if I can help it.

-Overheads: I'm working on a project right now where I thought I'd test out the ADL on overheads instead of Kick/Snare. I want more of these boxes. It sounds fantastic with my matched pair of BLUE Dragonflies. The imaging is superb and there is no sign of harshness coming from the cymbals. However on Overheads I find the ADL to be very dynamic, more than I'd imagined after the Kick/Snare test. The detail and progressive dynamic range make for an emotional listening experience. I need two of these bad boys.

-Bass: what can I say... Authority!! Really nice thick sound and extended low end ads a "sense of size" to 5 string basses. It goes down forever with no sign of sweating the energy needed. Tight enough with a sizable pillow for modern subwoofer oriented bass.

-Electric Guitar: Good character from both Dynamic (SM57) and condenser (BLUE Blueberry) mics. I've always found the Blueberry to really bring out the "truth" of a 4x12 cab and when mixed with a '57 or audix I5 the sound is lively and crisp without being brash. I have noticed how all the good qualities of the highs come into focus but non of the glassy, brittleness is present. This is great for DAW's.

-Vocals: I'm not sure if it's the vocalist who has improved with training or the ADL 600 but one or the other, maybe both have impressed me. My Dragonfly sound terrific on voice but the NADY TCM 1050 (Chinese tube mic) still demonstrates the "cheap Chinese" characteristics one would expect from a low budget mic. What the ADL proved to me was that the difference between mics is so much more apparent when the Mic Pre has the goods to offer. I think it's part of the detail this box is able to translate. It will reveal the true heritage of the front end you're using, without masking the good and restricting the bad.

All in all I've very impressed with this preamp and like I said, I need more of these for simultaneous recording.

On the down side the first one I got must have been damaged in shipping 'cause one channel didn't work. I returned it to Guitar Center and had to take their display model which turned out to have something wrong with Channel #1's instrument input and there is a "vibrating Tube" noise that has crepped into some recordings while tracking bass and monitoring at high levels. This is somewhat annoying and a little embracing after explaining to a client how a $2000 preamp is making a rattling noise on his bass tracks. I found that when monitoring at low levels this noise is not present and is obviously linked to vibrations being transmitted thru the tubes, so I suggest insulating the preamp from it's surroundings. Needless to say it's going back and a new one has been ordered for me. Hopefully this one will only do what it's supposed to and no more.

I can't wait to send my stereo mix thru the ADL 600. All in all this is a terrific preamp and like everything presonus makes....It looks good!

[Hype]

Originally posted by Anderton
Well Anthony, welcome to the thread! You did good with the ADL 600.

Actually, the only question I have is why you didn't use combi XLR/phone connectors for the line ins and outs. Seems to me a lot of people are using TRS phone jacks, and using combi jacks would make their lives easier.

I'm curious what involvement you've had other than the design. For example, do you do any overseeing of the manufacturing, or is that entirely up to PreSonus? The thing has great build quality...I assume you had some input into that. Inquiring minds want to know! <G>

Thanks again for stopping by.

That's a good question I'm guessing it's aimed at the pro market and they found no reason to mess with prosumer connectors, however a neutrik combo jack/XLR is a great invention and would be well served on the ADL 600. But we'll just have to pop for the high end XLR cable connectors for now or install combos in-house.

Great to see some "buzz" on this pre. I've been wondering what to get in the $2000 range and it was hard to make an informed decision without any available info.

Thanks!

[anthonyadl]

Originally posted by dr_chopz


Hi Anthony, great to have you here! Craig had popped the lid and listed the tubes you've decided to use. Great pics man, and first time I'd seen anyone mention the type of tubes in this baby.

Can you expand on why those selections and possible substitutions (type & brand) that can add different color or easier to saturate/orverdrive. For example, guys were raving about Mullards in various other pres. The ability to add diferent colors is another plus for tube pres.
Thanx,
Torry

Hi Torry, thanks for your question.
V-1 (12AT7) Because the overall design has a good deal of gain this tube is actually a low gain tube it makes for a quieter signal beginning into the next set of tubes, 6922 V-2, and V-3.

If you would like you could try a 12AX7, but remember everything is a trade-off the 12AX7 has more gain and more noise. A.

[anthonyadl]

Originally posted by Hype


That's a good question I'm guessing it's aimed at the pro market and they found no reason to mess with prosumer connectors, however a neutrik combo jack/XLR is a great invention and would be well served on the ADL 600. But we'll just have to pop for the high end XLR cable connectors for now or install combos in-house.

Great to see some "buzz" on this pre. I've been wondering what to get in the $2000 range and it was hard to make an informed decision without any available info.

Thanks!

As for the connectors on the adl 600. In the R-D
phase the group of engineers and producers did not comment on the jacks. A.

[Anderton]

<<I find very little need for compression because the ADL is doing something to the sound that makes it sound "somewhat compressed" in a good way.>>

Check out the attached picture in the second post, that shows what's happening to your signal. There is indeed some compression-type mojo happening if you turn up the gain enough. Yet I don't see clipping upon magnifying the peaks, so either it's a VERY soft clipping, or perhaps there's some other phenomenon limiting the peaks (transformer, maybe?).

Should be interesting to see what it looks like with drums....

[Anderton]

Sorry for the delay. The session at Maricam had to be rescheduled because we had a snowstorm here in Santa Fe, and I needed to deal with some issues around the house, like covering the firewood and such (note to self: skylights are nice, but make sure they don't leak before the winter season begins).

I was also kind of expecting some more comments, complaints, something...I did a little poking around on the web to see what other people are saying about the ADL 600, and it seems pretty much everyone is saying what I'm finding:

"Sounds great, built like a tank."

The only significant variation I've found is "Arrived with a problem, but PreSonus took care of it pronto. Now that it's working, it sounds great, and it's built like a tank."

So there really doesn't seem to be any controversy around this. No one is claiming it sounds wooly, or weird, or whatever. If the ADL 600 was meant to be PreSonus' ticket into high-end audio respectability, it sure seems like it got them there.

Anyway, things are settling down here, so I'll finally get a chance to try the ADL 600 with some more signal sources. Well, those are the breaks with a real-time review :) Thanks for your patience.

[Anderton]

As I said at the beginning, I’m not a boutique kinda guy, so it’s been interesting to hear (and see) that yes, the ADL 600 does make a difference to the sound. In my latest tests, I found that drums benefit from the “ADL 600 sound” as well.

I’ve been trying to make these tests as tough as possible – for a couple grand, you want something that really performs, not just something that does its thing under certain conditions (e.g., when it’s overdriven). For the electronic drum test, I set up an Ensoniq ASR-X Pro because I’ve always liked the “punchiness” of the drum sounds, and I wanted to see if the ADL 600 preserved that. In order to test the ADL 600 solely as a processor, I recorded two files: One with the ASR-X going directly into a PreSonus Firebox, and the other, with the ASR-X going through the ADL 600 before going into the Firebox. By going through the Firebox in each case, any contributions it made to the sound would cancel out.

I didn’t want clipping to enter into the equation, so not only did I set the Firebox levels carefully to make sure there wasn’t any clipping, there was no clipping in the ADL 600 either. I wanted to see if the ADL 600 “mojo” could exist with just the sound of the unit itself. I recorded the two different versions in Wavelab, then normalized the peaks (even though the levels appeared to be evenly matched) so there would be a “level playing field.”

The attached MP3 file of the ASR-X going through the ADL 600 is unfortunately limited to 160kbps due to file size limitations for attachments, but you’ll still hear a difference compared to the file attached to the next post. The difference is more obvious with full resolution WAV files, but the fact that you can hear the difference even with MP3 is pretty surprising to me. (If you don’t near much of a difference, try listening on headphones).

Click on the attachment to hear a short drum part going through the ADL 600 – Firebox chain.

[Anderton]

The file attached to this post was recorded identically to the previous one, but through the Firebox only. What’s interesting is it sounds just fine, but the one going the ADL 600 has a certain quality that makes the non-ADL version sound more “polite.” Through the ADL 600, the drums have more presence and power, and seem to hit harder. It’s a subtle difference, but not so subtle I had any problem whatsoever differentiating between the two.

Click on the attachment to hear a short drum part going through the Firebox only.

As was pointed out in a previous post, subtlety may not seem that impressive when listened to in isolation. But as you record more parts with that “extra 10%,” it all ads up to a more satisfying overall sound. The ADL 600 really brought out the best of ASR-X. I didn’t feel the sound was so much “processed;” it’s more like the ASR-X character remained intact, but was just enhanced.

So were my ears playing tricks on me? Did something sound better just because I knew it was going through the ADL 600? Check out the next post.

[Anderton]

A good way to verify what’s happening with your ears is to use your eyes too, so I tiled the two waveforms in Steinberg’s Wavelab for comparison. Click on the attachment to see a visual comparison of the two waveforms.

The upper waveform shows an excerpt of the version going through the ADL 600/Firebox, and the lower version, the same drum part going through the Firebox by itself. Again, let me emphasize there was no clipping anywhere to influence the sound.

Look at the area outlined in red. Clearly, the ADL 600 has added a subtle compression, raising the average level. Yet the peak hasn’t been “squashed” – it retains its character, and the transient even seems a bit more pronounced than the lower waveform. The peak is higher, extending to the maximum available bandwidth.

Now check out the area outlined in yellow. Again, the ADL 600 has raised the average level, but note how the transients once more retain their identity; they aren’t “flattened” at all, which is why you don’t lose the crispness of the drum transients.

While the difference between the two waveforms is subtle, as is the difference in sound quality, the waveform pictures make it very clear what’s happening. So all of you who are hearing more “depth” or “presence” or a bigger sound when running tracks through the ADL 600, rest assured it’s not just wish fulfillment to justify spending the bucks: There’s a measurable, repeatable difference.

[Anderton]

Okay, so a bunch of you have downloaded the examples and seen the JPG...whaddya think?!?

[Lee Knight]

Originally posted by Anderton
Okay, so a bunch of you have downloaded the examples and seen the JPG...whaddya think?!?

Really interesting. Transients are pronounced as is low level detail... I want one. I wish I had a couple of grand.

[diamondjim]

Nice work, Craig!

Its good to get the visual impact as well as the subjective audio. This was my 2nd big gear purchase, following on the heels of an RME FF800, and having the visual helps explain what I am hearing. It would be interesting to compare this result with a Neve Portico, or Groove Tubes Supre.

I would show this to my wife as proof of my amazing skills at picking gear, but she would just roll her eyes......she calls it my vocal warmer upper thingey.

[modul8]

The mojo...um... I mean... compression is distinct and has, dare I say, an almost "just right" quality to it. The Kick and snair exhibit excellent benefits.
I think when I can afford to add a new color to my humble preamp selection, the ADL will be at the top of the list.
If I may request, I would be interested to also hear the tonality differences you mentioned when pushing the input. I feel this will give us a better sense of the ADL's sonic dimensions.
Thanks again for your efforts! I am waiting with great anticipation for the synth results :-)

[Anderton]

<<If I may request, I would be interested to also hear the tonality differences you mentioned when pushing the input. I feel this will give us a better sense of the ADL's sonic dimensions.>>

If I have time, I'll go back and revisit this. I will say that the next (and final) batch of NAMM videos I did for the site used the ADL 600 in the vocal chain. Even when squished down via WMA data compression, you can hear a difference compared to the narration on previous videos.

[Anderton]

<<Thanks again for your efforts! I am waiting with great anticipation for the synth results :-) >>

Me too! What I want to try is taking the output from Cakewalk's Dimension Pro and Rapture, which have exceptionally clean audio engines, running it through the ADL, then bringing the result back into Sonar. I have a feeling the ADL 600/Dimension Pro/Rapture combination would be a good one.

[diamondjim]

Craig,
I am curious about how you will approach this. Are you going to take single audio tracks out, and then record them back in? If so how will you adjust for latency?

Or will you take the entire stereo mixdown and record it, for example:
1. export to stereo
2. import into a new project, play that through the ADL
3. record it back onto a new track, and toss the first

I am anticipating doing the second approach to some of my old mixes, just to see how they sound. I.e. using the ADL as an outboard mastering processor just prior to dithering down to 16 bit.

[Anderton]

<<I am curious about how you will approach this. Are you going to take single audio tracks out, and then record them back in? If so how will you adjust for latency?>>

Well in this case, latency doesn't matter as I just want to generate a set of tracks for comparison. But if it was a "real-world" situation, I'd just compare the new waveform to the old one visually, and line up the peaks.

FYI Cubase SX is set up to do this kind of thing -- it will "ping" your system to measure the delay, and compensate automatically.

[ivorycj]

Hey Craig,

Thanks for doing this -- you give a lot of creedence not only to HC as a 'pro' forum, but also to these products that you review. I just got my ADL600 today -- I can't wait to play my K2600 through it :)

[Anderton]

I decided not to try bringing synth sounds of the computer and back again the ADL, as the additional conversions would likely skew the results. Instead, I figured out dragging out a good old-fashioned hardware synth, and recording it both with and without the ADL.

But as I wanted to try out both synths and mixed tracks, I figured why not have a dual-purpose test, and try a mixed track of synths?

The signal source was an Ensoniq TS-10 with some sequences I had loaded in some time ago. The reason why I chose these was because they had really punchy drums, some sampled acoustic guitars with a lot of “zing,” some analog-type handclaps – a nice mix of sampled “real” sounds and synthetic sounds. I was hoping that by using a diverse collection of sounds, I could readily pick out differences in individual tracks as I compared the ADL-ified version with the straight version.

Another point of interest is that I believe the TS-10 response tops out at about 15kHz. I didn't want to have too many highs, so I could hear if the "sparkle" that the ADL seemed to add would work with a more muted signal source. In other words, was the ADL generating harmonics, or working with the ones that were already there?

I did the usual trick of recording one track straight through the FireBox into Sonar, then another track through the ADL 600 and then through the FireBox into Sonar. On playback, as I switched back and forth between the two, the differences appeared to be subtle. I thought I recognized the ADL 600 "signature," but was concerned that because I had already listened to so many signal sources through the ADL 600, I was “psyching” myself into hearing something that maybe wasn’t there. Also, as I transitioned between soloing one track and another, there was a long enough pause that my auditory memory was fading by the time the second track was lined up and ready to go.

I needed some way to do more of a blind test. So I took identical sections from the two tracks, put them end to end, and looped the combination. I then left the room for a minute, came back in, put on headphones, and listened. The looping process was already occurring, so I had no idea whether I was coming in for the first segment (recorded through the ADL 600) or the second segment (no ADL).

Well, I gotta say…as one segment played back, I was absolutely 100% sure it was the ADL 600 – it had that definition/compression/peak massaging mojo. I looked at the screen and sure enough, the first segment of the loop was playing.

This is also an interesting example of psycho-acoustics in reverse: Because I wanted so much to be objective, when I knew which segment was which, I tended to hear the similarities more than the differences. When I came into it “blind,” the differences between the two segments were obvious. It was easy to tell one from the other.

Unfortunately an MP3 example at a high enough bandwidth and of sufficient length won’t fit in the allowed file size for a post, so in a bit, we’ll get graphic.

[Anderton]

I put the two waveforms into Wavelab, and was surprised that the “higher average level” effect I’d seen on individual instruments wasn’t as pronounced here. With the ADL, the peaks had been softened a bit, but other peaks were brought up. This didn’t seem to jibe with what the waveforms looked like on previous tests, but the sonic signature was the same.

So what exactly is that sonic signature? Well, of course this ventures into the wildly subjective. But I would identify the following as the components of the “ADL sound.”

“Punchier” transients. It seems counter-intuitive, as the peaks are typically reduced a bit to allow for a slightly higher average level. Yet without going through the ADL, peaks sound more “smeared” and less distinct. It’s not the FireBox doing this, because as it’s following the ADL, it would smear the ADL’s transients. It seems to me that something within the ADL is actually “sharpening” the transients. Slight ringing from the transformers, maybe?

More defined midrange. The sense I get when listening to the mixed tracks is that the stereo positioning is more precise, and it’s easier to pick out individual instruments. This seems particularly true with harmonics from bass, which are brought out a bit. This gives the illusion of better bass response, because the bass sounds fuller rather than having more of a low frequency “blur.”

”Sweet” high end. Put a screechy FM patch through the ADL, and you’ll hear what I mean. There’s a certain sparkle that’s very subtle.

Better bass. It’s hard to describe what I’m hearing here, because the waveforms don’t seem to indicate that the bass is any louder; in fact, the reverse appears to be true. But it just seems “rounder.”

Slightly higher average level. Of course, just increasing a signal level somewhat will make the bass and treble seem larger, due to the way the ear works. But I went out of my way to try to also listen at lower (not matched) volumes compared to the reference signal, and you could still hear the effects mentioned above.

All right…let’s see what some spectrum analysis says about all this.

[Anderton]

I used Wavelab’s 3D Spectral Analysis feature to analyze the two different tracks, and besides, it looks cool. Click on the attachment to see a picture of the two spectra; each signal lasts a little under 2 seconds. The upper one is going through the ADL 600.

At first glance, the differences appear to be minor. And that’s right, because the ADL is about adding a subtle character to the sound, not hitting you over the head. Still, as you look closer, there are some significant points of interest.

The top peak is definitely rounded off a bit, and not quite as high in amplitude. But the big difference extends from about 50Hz to 500Hz. The ADL signal clearly has a slightly higher level, with more definition. Note how the yellow bass region “blob” on the lower shot around 50-115Hz is much more defined in the upper one. And while it’s not all that easy to see, look in the upper shot around 500-1500Hz, and follow the response toward the left. Those blue ridges are higher, and more defined, than what’s happening in the lower shot.

Once again, we have a strong visual correlation to what we’re hearing. Interesting…

At this point, I think I’ve pretty much found out what there is to know about the ADL 600. Even though I couldn’t book a make-up session (at Maricam Studio) for the one that I canceled during the snowstorm, I did some acoustic recording here and the ADL stayed in character – I was mistaken to think that I would need to go to a studio specializing in acoustic recording to hear the difference. Percussion (shaker, tambourine) in particular sounded wonderful.

So I’m going to sleep on this a bit, mull over some additional thoughts, and present my conclusions next. As usual, that doesn’t mean the end of the Pro Review, as there will likely be follow-ups and additional discussion. But I feel I know the unit really well, and it’s time to wrap all this data and all these subjective impressions up into a nice, compact package.

[Anderton]

You never know what's going to happen with a Pro Review, which is part of the fun for me, and of course, a bit of a nail-biter for manufacturers. Of all the Pro Reviews done so far, this has probably had the least amount of interaction from both readers and the manufacturer, even though it's clear a lot of people have been following the review.

Why is this? I decided to spend some time checking out what people were saying about the ADL 600 on other forums. It could pretty much be summarized as: "Sounds great, built like a tank." This is basically the same conclusion I came to (although I'd like to think this review delved a little more into the objective reasons behind that conclusion). And when users did post here, their reaction was pretty much the same as well. I even called up EQ magazine's editor, Eugene Robinson, because I knew they had done a shootout recently with the ADL 600...yes, their reviewer liked it too.

There was one variation I found a couple times: "Well, it didn't work when it arrived, but PreSonus took care of that. Sounds great, built like a tank."

So basically, although the Pro Review format allows "checks and balances," there seemed to be virtually zero controversy around this piece of gear. I expected at least some "Well I don't hear anything different" or "$2,000+ is a lot for a stereo mic preamp" or even a few "tubes good/solid state bad" comments. Nope. Just "Sounds great, built like a tank."

I believe that PreSonus was hoping the ADL 600 would update their image and show they could make boutique-type, pro-level gear more accessible but without compromise. Okay, $1,000 a channel still isn't exactly the budget zone, but when you look at the build quality it's clear that a lot of effort went in to designing and manufacturing this amp. And given what it does to a signal, there will be people willing to pay that grand per channel. If an image update was part of what PreSonus set out to do with the ADL 600, it was a good move because it has garnered the company a "buzz" ih pro audio circles it didn't really have before.

[Anderton]

When I started this Pro Review, I didn't really know what to expect. I've worked with enough "boutique" gear over the years to recognize that a lot of it does bring something special to the table - but some of it seems way overpriced, and more "emperor's new clothes" than anything else. Where would the ADL 600 fall?

Overall, it does indeed justify its price tag - not by being a "straight wire with gain," but by adding character to the overall sound. "Character" is always a dangerous concept, because it might be a character you like, but it also might not be. This is particularly the case with tube gear, where "character" may mean distortion or ringing from transformers: Fine for some signals, but not for others.

The ADL 600 has a character that really seems to flatter just about everything you put into it, from individual instruments to complete mixes. It does this by what appears to be a very gentle peak limiting/compression effect, and that's easy to see on the waveforms attached to some of these posts. There are also some frequency response things going on, as evidenced by the 3D spectrum analysis shots. Subjectively, I'd say there's more definition overall, and a very smooth bass range.

Those who expect these changes to leap out at them will be disappointed; the ADL 600 is much more about subtlety. It really comes into its own when you use it on multiple tracks and hear the cumulative difference, or use it to accentuate individual tracks. I also like what it does to mixes, and the surprisingly low noise level means yes, you can consider this a legitimate piece of mastering gear.

I really have only two complaints: Using XLR-only connectors in today's world, while "pro," isn't as practical as using combi jacks with XLR and 1/4" TRS connections. It's not a deal-breaker, but with so much gear using 1/4" TRS balanced connections, you'll find yourself looking for adapter cables perhaps more often than you'd like.

The other issue is the instrument input impedance. 100k is acceptable, but on the low side of acceptable. To squeeze every last bit of response out of a guitar or bass with standard pickups, the input impedance should be at least doubled...and I'd prefer something between 500K to 1M. This doesn't make a huge difference to the sound, but given the level of detail in the ADL 600's design, I'm surprised this detail was overlooked. (I also assume it would be relatively easy to mod the ADL 600 for a higher input impedance on the instrument input, although I haven't seen a schematic so this is speculation.)

Realistically, though, these complaints are minor considering the positives. Frankly, the idea of a box that just plain makes things sound a little better is hard to resist. Whether the improvement is enough to justify the ADL 600's expense is difficult to say; for example, if you don't have a really good mic, you're probably better off buying a really good mic than taking advantage of the fact that the ADL 600 can make okay mics sound better. On the other hand, if you do a lot of work with electronic sound sources and want something that can give them a more organic feel, then the ADL 600 might be an excellent investment. I've certainly enjoyed its visit (and so did the narration that used it instead of stock preamps).

Bottom line: This isn't an "emperor's new clothes" situation, but a solidly-engineered preamp that delivers what it promises. Some would say that it actually delivers more, because while it's billed as a tube preamp, it does a lot more than just make mics louder. Either way, it's a mighty fine piece of gear. Anthony DeMaria and PreSonus have every right to be proud of their new baby.

Thanks again for your participation, even if you just lurked :). I've pretty much said all I have to say on the subject but feel free to carry on the discussion, particularly if you have any further questions.

[gsbe]

Originally posted by Anderton
Frankly, the idea of a box that just plain makes things sound a little better is hard to resist. This one comment was worth wading through the 6 pages for. I love it!

I'd like to see more direct comparisons to similarly-priced units in the future. You do a great job at quantifying what you're hearing with the various graphs. Having an A/B comparison such as the user posted with a Langevin or similar pre would have furthered these analyses. Adding in a third, popular less-expensive unit would have really helped, also. Some ideas for the future...

Thanks again for a great thread,
Graham Spice

[Anderton]

<<This one comment was worth wading through the 6 pages for. I love it!>>

Well, it was worth doing the Pro Review just to be able to find a box that actually does that. Nice to know not everything is "emperor's new clothes."

<<I'd like to see more direct comparisons to similarly-priced units in the future. >>

That defeats the purpose of a Pro Review a bit, which zeroes in on one particular piece o' gear. You're asking for more of a shootout kinda thing, which is a little more daunting to pull off, what with having to deal with multiple pieces of gear. I don't mind throwing in some comparisons, but only if I already know the gear with which I'm comparing the unit.

<<You do a great job at quantifying what you're hearing with the various graphs. Having an A/B comparison such as the user posted with a Langevin or similar pre would have furthered these analyses.>>

The big problem there is the 102k limitation on attachments to posts. You can't really do great fidelity unless it's a very very short example. Hopefully I'll get some hard disk space on the server to which I can hot link examples in the very near future.

Thanks for the comments!

[Anderton]

Hey everybody, the ADL 600 is being shipped back to PreSonus tomorrow, so I won't have it to refer to if you have any further questions.

Great box, though. I was kinda hoping they'd forget they'd sent it here :)

[SteveE9C6]

I followed this and read everything I could about it. I don't have a huge budget and my mic pre's are currently limited to my Onyx 400F, Presonos Firepod, and my new Joe Meek TwinQ.

I now have one of these on order. I suggest folks look around for better deals. I saved several hundred dollars over the M.A.P. price. (After spending over $20k at that sweet place, they won't budge off of MAP... I ordered this and a new Neumann TLM49 form someone who would budge. With the money I saved, I can get some new software:D )

Regardless.. I appreciate the effort that went into this review.

My one dissapointment with the ADL600? No digital out. Any digital out would have been a real boon. I guess decent convertors would have upped the price though.

Steve

[Anderton]

<<My one dissapointment with the ADL600? No digital out. Any digital out would have been a real boon. I guess decent convertors would have upped the price though.>>

Well, the ADL 600 has a 100% analog signal path. There's no digital in it from which you could derive a digital out, so you're better off just choosing the A/D of your choice and going from there.

[SteveE9C6]

I'm running the outs into channels 5 and 6 in the Onyx 400F. That way they don't go thru the Onyx preamps too. Works great. This really is a nice preamp.

Craig, I know it's all analog. What I meant was the cost of adding a A/D convertor inside the box would have been cost prohibitive. I suspect most folks who have this pre already have premier convertors in house.

Still.... 2 thumbs up for this preamp!

[Brittanylips]

Great review! I have heard similar praise about the ADL600 from other users who are putting this thing high up on their echelon of go-to preamps, and it is now high up on my wish list.

Also, I thought I might add that I have dealt with Presonus in the past and – with reference to the thread “are people more mean spirited?” – if anyone ever wants evidence that good-spirited people are out there as well, just give Presonus a call. Without exception, the guys at PreSonus are consistently friendly and helpful and if there is ever a problem, they go out of their way to make sure that it is quickly and entirely fixed. FWIW, in my experience, they really treat their customers right.

-blips

[mr. moon]

Hi folks,

I just want to make you aware of an issue with the ADL600 which was described in a review (by Paul J. Stamler) published in the October issue of Recording magazine.

Here's a quote from the article detailing the problem:

"The other anomaly I measured was the input impedances. These are marked on the selector switch as 1500, 900, 300 and 150 ohms, but when I measured them, what I found was quite different (see Below). The range of impedances available from the ADL 600 is considerably less than stated, and an input impedance >1 k (as recommended by most makers of condenser microphones) is only available with the 20 dB pad switched in. (Of course, condenser mics are hotter, so using the pad would probably be a reasonable choice.)

Impedence:
Listed-Measured-Measured(20dBPad)
1500-----785-----1256
900------526-----696
300------453-----560
150------177-----270

PreSonus confirmed my results; the discrepancy is due to a jumper resistor that was used in tests and was left on the first production run of these preamps, which can be easily removed if the user desires impedance settings that match the front panel specs. Concerned users should contact PreSonus about how to do this; my feeling is that the effect will be audible but small..."


I own an ADL600, so I contacted Presonus about this issue via an email to their technical support stff, and Presonus stood behind their product 100% and satisfactorily resolved this issue on my unit.

The difference to me between the before/after fix, was more dramatic than suggested in the review. I noticed that it REALLY opened up my Gefell 930 when recording an acoustic guitar; much larger and lusher image, to my ears anyways.

Hope this helps!

-mr moon

NOTE: I will also be posting this under it's own thread ("ADL600 input impedence issue") in the recording forum

[jahboo]

Greetings ... I use a Soundcraft Ghost 32 LE console and an Alesis HD24 as the basis of my home studio ... I was wondering if I would have any benefit from the ADL 600 during mixdown ... running the main outs of the soundcraft into the adl 600 or main inserts ... and then into my Alesis Masterlink ... I'm sure it would really come in handy for all kind of uses ... but that was my main plan for it ... between the console and masterlink during mixdown ... any thoughts ? thanks ... jahboo

[ricknaqvi]

I was wondering if I would have any benefit from the ADL 600 during mixdown

Absolutely. There are a lot of engineers running their final stereo mix through the LINE inputs of the ADL600 and hitting the tubes and transformers for a little extra 'love'.

We even have heard from some mastering guys that are using it in that way.

The ADL is not a 'low fi' sounding preamp. It has an extremely wide frequency response and headroom. So it lends itself to an overall mix in a really musical way without robbing the mix of any fidelity.

[Anderton]

I just noticed the new post (happened while I was in Frankfurt, I have an excuse!) and agree with Rick. As mentioned during the course of the review, the ADL 600 does "something" to the sound that makes it more defined and just, well, better-sounding. It's not exactly an inexpensive solution, but based on what I heard, there's a reason why it costs what it does.

[Erik-RMCAudio]

I'd just like to thank Craig for the great review. As of a couple of years ago it was hard to find decent reviews on gear such as this. I'd also like the thank Presonus for making such a nice product. Let's see some more items like this. :)

[syncretism]

Craig,

Consider using a proper ABX applet for blind listening - there are fewer hoops to jump through, and you can be sures of the test's integrity:

http://www.pcabx.com/


Hope that helps!