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moody
12-26-2002, 04:05 AM
I have a small mono pa head that I have used on and of for practice and stuff (not really big enough for full PA work). The outputs are hi fi style screw terminals.

I am not sure what all of the terminals do however - they are labeled as follows

8ohm (points to 2 terminals - the ones I use)
com
70
100

There are also a few unlabeled terminals in the same strip which I assume are unused.

moody
12-06-2003, 05:28 AM
Wow, almost a year with no replies....

(Sorry, going through old posts).

RickJ
12-06-2003, 05:59 AM
I'll wager that one of the 8-ohm terminals is jumpered to the "com" (common) terminal.

70 and com will push a 70-volt distributed system. Each speaker on such a system requires a 70-volt transformer.

100 and com is the same as above, b/w 100-volt transformers.

The benefit of distributed systems is you can use a lot of speakers without worrying about impedance issues. Many of the multiple ceiling-speaker systems you see installed in restaurants and banquet halls are 70- or 100-volt.

tlbonehead
12-06-2003, 08:08 AM
Originally posted by moody
I have a small mono pa head that I have used on and of for practice and stuff (not really big enough for full PA work). The outputs are hi fi style screw terminals.

I am not sure what all of the terminals do however - they are labeled as follows

8ohm (points to 2 terminals - the ones I use)
com
70
100

There are also a few unlabeled terminals in the same strip which I assume are unused. Isn't common the ground,or negative and then the two that are marked 8 ohm,the positives?

moody
12-06-2003, 03:12 PM
Originally posted by tlbonehead
Isn't common the ground,or negative and then the two that are marked 8 ohm,the positives?

Maybe it's supposed to... but I screw speaker lead to the two 8ohm terminals and get sound.....