amp circuit help


I have 6 of these amps (schematic attached.) taken out of a hospital and am trying to hook them up to my Yamaha reciever for an awesome looking home theater system but can't figure out what to do to get them to work. They worked in the hospital but I don't know enough about circuits to figure them out. I know I have to remove the step-up tranformer as it generates 70 volts, but what eles do I have to do. Audio in on the N1 & C terminals, out before T1 but the amps don't seem to turn on ( power is on). Ideas????

Thanks for reading.



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Paid Member
2004-06-06 8:31 pm
Georgetown, On
Hi Scott,
Djk is right, they look like they will sound nasty (as in horrible).

You did get free chassis and transformers plus whatever else is useable. Why not build a DIY amp project? Build one and once it's going, build the rest. You are correct that the 70V line transformers must go.

A neat idea but would the final result be any better than just using the Yamaha? Right now I have it powering 6 mission bookshelf speakers & 2 100 watt subs, plus a Harman Karden (200 watt) powering 6 AR satelites speakers and a 100 watt sub. The goal is to use all the speakers but only one source as with two, the sound seperation gets a little blended. This is in a large rec room mainly for movies. As you can imagine I like a full sounding system.
Thanks Scott