Hafler 945 Preamp Issues - diyAudio
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Old 21st March 2008, 02:21 PM   #1
john65b is online now john65b  United States
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Default Hafler 945 Preamp Issues

Hey all,

I fixed a friends amp the other day and in lieu of payment he gave me a broken Hafler 945 Preamp/Tuner.

Theres a Relay on the preamp board that went bad - I could tap it a few times and the channels would come in fine. I replaced that (12v coil) relay and all was good, but I noticed the balance is tripped up. I have the checked the mono button, and when on, the balance pot has no effect.

But when off, I turn the balance pot all the way to one side, both channels just get a bit fainter.

When I unplug one channel from the inputs, only that channel works as it should.

Seems I may have tripped something up on the balance replacing the relay. But then again it may have been an issue all along and have nothing to do with the relay.

I have also scrubbed down the preamp and PS boards with Alcohol to clean it, and replace the main PS caps...

Anyone have a schematic of the Hafler 945 preamp or know what could be an issues here??
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