I have a Schiit valhalla 2 preamp. It was working quite well till last month, after which it started giving a problem of losing one channel after about an hour of usage. When I turn on the amp, it plays just fine, then after around an hour or so, the left channel starts to distort/crackle and then mutes itself. It then restores itself after about a minute and sometimes it doesnt. I have tried a few ways to debug the issue from Changing to New tubes as well as changing New tube sockets as well as changing to a New potentiometer. But the problem remains. Tried cleaning the input and output rca Jacks as well but to no improvement. If I use a different preamp, everything plays just fine, so no issues with any connected equipment as well.
I suspected a cold solder joint somewhere, but could not really find one upon inspection (but it may be there)
Can a failing coupling capacitor be a suspect ? Tried using a magnifying glass to inspect a cold solder joint but could not find one. Whatever looked dry, i reflowed New solder on them.
Please advise
I suspected a cold solder joint somewhere, but could not really find one upon inspection (but it may be there)
Can a failing coupling capacitor be a suspect ? Tried using a magnifying glass to inspect a cold solder joint but could not find one. Whatever looked dry, i reflowed New solder on them.
Please advise
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Looks like there are some transistors in there, maybe as a current source for the tubes? Those can fail or become intermittent. If that's the case, unless you have a schematic you're better off to contact Schiit about a repair. You may want to save yourself a lot of trouble and do that anyway.
I have written and email to the company asking for the schematic. Hoping to get one from them. If not, how do I make sure that the transistors are the cause as you have pointed out ? And if they are, then just replacing them with the value mentioned on them (if it is) be easier ?
Also I forgot to mention that when one channel crackles and goes mute, and if i tap on the top or back of the amp, it comes back. But this does not work always.
Also I forgot to mention that when one channel crackles and goes mute, and if i tap on the top or back of the amp, it comes back. But this does not work always.
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I doubt they will send you a schematic. You could replace the PNP's, they're not expensive, if you can determine what they are. Tapping would usually mean an intermittent connection, especially one that happens when the unit warms up and the solder joints can expand and contract. Maybe someone else will have a better suggestion.
