Posted by fxbill [ 66.229.170.101 ] on October 15, 2006 at 17:15:30:
Hi,
I recently picked up a Melos power amplifier. I believe the model is a Mat 185, but it doesn't say anywhere. It runs a quad of 6kg6's and is a huge 75 lb beast.
The left channel operates great, but the right channel has a problem with the auto bias circuit. Each tube has it's own led next to the tube and on each channel you can see as one led grows brighter the complimentary tube's led gets a little dimmer. On the right channel, however, one led is at full brilliency all the time and the other doesn't light at all. Needless to say the tube with the full lit led glows cherry red within a minute and the right channel just makes an occasional shuddering noise through the speaker.
I have swapped the op amps from the right side to the left side with the same results, but can't fo much farther without some sort of schematic.
Does anyone here have one, know where I could get one or know of a reasonable repair shop that knows Melos equipment? I love the sound from the one operating channel and would really like to get this unit repaired.
Thanks for any help you might offer!
Bill
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