Try the power supply for the right channel on the left. Also, check the cables going to the left channel. You may have accidentally reversed the IC's.
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I am a little unclear about the recent history. You say you originally heard no problem with the right channel, only the left channel was without signal. And incidentally, you mention that only the L channel was grounded. When you replaced the fuses, did things get worse, in that you lost the R channel as well? It seems so, based on what you wrote.
Have you opened the chassis, at least to see by visual inspection whether there are any loose wires? The fact that only the L channel was grounded should be neither here nor there, because if you're talking about chassis to chassis grounding, the grounds are probably common to each channel. I don't think there is a problem with your transformer, because you would have heard nothing at all or something more catastrophic might have occurred, if the AC voltage coming out of your transformer is seriously off the mark. BUT do you perchance have an AC voltmeter with which you can check it?
You have read entirely correctly:
- I lost signal entirely when I went back.
I opened the amp up - no burning smells - not sure about loose wires
I am confused due to having heard something from the right channel initially.
Spoke to a guy called Ben Jalopy from Highend audio repairs in NYC and he thinks it is most likely a capacitor issue.
If this piece of kit wasn't so rare I would probably do the work on it myself, but I think I have roped a good technician into dong the work.
My real fear is losing the original fets if they are damaged - I am told they are the best thing about this phono stage...
There is a company on the West Coast, the name of which escapes me, that carries a lot of supposedly no longer available transistors, including FETs. I was able to buy the full complement of transistors needed for my 1980-vintage Beveridge amplifiers from them. I will look for the name later today, but you may find it by simply doing a google search on the needed FET, if indeed you need a FET.
Hi Lewm - I think I have found the 'unobtanium' company. Trust me it was a flipping pain in the backside to find them - I felt like a stalker tracking posts by John Curl on another site. I spoke to a chap called Ben Jalopy - a pretty decent guy who reckons that it is most likely the old Panasonic electroytic caps that have gone bad. He reckons Elna replacements are the way forward.
The company you found, is it in California? If so, they're a really good source.
I feel remiss in not thinking about the electrolytic capacitors. By all means, they need to be replaced if still OEM. One can only hope that damage has not already been done to one or more of the FETs.
Last year I bought a Klyne 6LX. I built a new outboard supply for it using an overkill toroid from Antec, and I replaced all the lytics on the audio chassis with ELNA Silmic IIs. I also upped the values of the PS filter caps. Lots of bang for the buck.