Noise issues with Crack

[mikko]

What pins on tube sockets are related to right channel?
I built my Crack in 2014 and added Speedball about a year ago. I haven't had any problems until recently. I started to hear buzz on the right channel that comes and goes. Just like mentioned in this thread earlier. I have re-soldered 9-pin socket  twice and 8-pin socket once. No luck. Now I'd like to concentrate the joints that are directly related to right channel. I have changed the both tubes many times, unplugged the RCA cables etc. basic things.

 

[Paul Birkeland]

I would resolder all the joints in the amplifier, not just the sockets themselves.

If you have a really cheap pair of headphones, you can plug them into the amp while it is running and flipped over, then use a wood chopstick to poke all the connections in the amp.  If poking something inside the amp produces a noise or static, you know where you need to do a little additional work.

-PB

 

[hpjun]

I had a problem similar to this so I thought I would chime in. Try wiggling those long wires that go from rca input to the pot and see if you hear any differences.

 

[mikko]

OK, I see if I can find some ”sacrificial headphones” to use on further investigations. I already got scared some time ago when one 6080 died with loud crackle on my HD-650 and sparks inside the tube. This buzz problem was present before that event, and at first I thought “OK, it was just tube dying that caused the buzz and now it finally died completely.” I changed the tube, and exactly the same buzz is still there.