Right channel noisy. Help troubleshooting

[denti alligator]

I've been sitting here now for about 15 minutes or so, maybe slightly more. And it's been totally silent, until a second ago, when there was one brief burst of noise. Now it's quiet again. So I doubt it has been totally quite the whole time.

[denti alligator]

Woke up this morning and it’s noisier than ever. 

(Edit: it’s pretty chilly in the morning. Heat kicked in and since then it’s been silent…)

[denti alligator]

Little over half way through the week. It’s been running non-stop. Sadly the hope I had around days 2-3 has vanished. It’s been pretty consistently noisy for the last couple days. It does sometimes go for longer without any noise at all, but rarely for more than a minute or two. 3 days to go. Maybe it will burn through whatever contaminant is in there after all. I’m not counting on it, though.

[denti alligator]

OK, so it’s been a week that the amp has been on. This morning it is still making that same noise. Where do we go from here? I am willing to begin replacing parts on the right channel, if that’s what it takes. But it would be good to know where to begin. I’d rather move slowly and replace one part at a time to see if it makes a difference. I have wire. I would need new resistors and capacitors, if these might be the culprits. I could order these myself or if possible I would happily buy them from you.

[Paul Birkeland]

Since grounding the grid of the 2A3 allowed the noise to remain, you would want to replace:

4 pin tube socket (if it isn't the one I already replaced)
Both terminal strips bolted to the 4 pin socket
The 2K and 3K resistors
The 220uF bypass cap
The hum pot
The 22 ohm resistors

That would be my next step based on the information provided; it is not necessarily the solution.

[denti alligator]

Thanks. What about the

220ohm carbon film resistor (red, red, brown, gold)

and

0.15ohm 3W (brown, green,
silver, gold, violet)

[Paul Birkeland]

Those are parts are unlikely to create noise problems if there's semi-conductive residue on them.  The grid stoppers because there's no current flowing through them, and the 0.15 ohm resistors because they are already such low resistance that they are unlikely to be influenced by anything short of a dead short.

[denti alligator]

OK, thanks. I'm getting the parts from Eileen. The socket is new (the one you put in) and I have extra 2K wirewound resistors. I'll start by replacing the 2k resistor, which I have on hand.

[Paul Birkeland]

I would suggest doing it all at once if at all possible.

[denti alligator]

I would suggest doing it all at once if at all possible.

OK, will do. Though it would be kind of nice to know what, exactly, was at fault—if indeed any of these replacements fixes it.

[denti alligator]

I’m replacing the parts Paul recommended to replace on the right side. As I’m doing so I’m seeing something that seems to me the obvious source of that green stuff: the 0.15ohm 3 resistors on the socket. They have a primarily green color, are right there where the green stuff was found, and I’m seeing that tiny bits of the outer green part of the resistors has chipped off. It’s the same green color that was there. Could I be that I put too much heat on those and the outer part (what’s it made of) “melted” down onto the socket?

Could these resistors be damaged in some way? They are not among the parts you told me to replace.

I’ll report back later, once I’ve switched everything out.

[denti alligator]

OK, everything has been replaced. I flipped it on and it was noisy. Damn. But that only lasted about 10-15 seconds. Like it needed to clear its throat first. Mind you, this is only happening on the right channel, not the left, so this isn’t the usual slight sound of turning the amp on. But now it’s been quiet for about 5 minutes with only very, very, very tiny little pops every now and then. Fingers crossed. This might be the end.

[denti alligator]

Right, spoke too soon. It’s definitely quieter. But those pops and scratchy sounds still come in every now and then. I’m keeping track of it.

By the way, with the balance turned all the way to the left channel I still hear the noise in the right channel. Not sure that helps identify anything.

In setting the hum pot I noticed that the right channel also has more hum than the left. And if I put my ear up to the mid range speaker I can hear a constant low-level scratchiness. So it’s still there, all the time, but it only gets loud enough to hear from listening distance about once every minute or so, then it quiets down. Certainly better than it was before, but not totally gone.

What other parts might I try replacing?

(Note that I didn’t replace the wiring, just the parts Paul listed above.)

[Paul Birkeland]

I’m seeing something that seems to me the obvious source of that green stuff: the 0.15ohm 3 resistors on the socket.

What about the hundreds and hundreds of other 0.15 ohm resistors in everyone else's Stereomour kits?  How about the tens of thousands of these resistors that have been sold over the last decade and installed in consumer electronics? A little bit of critical thinking in situations like this can go a long way.

[denti alligator]

Look, no need to get snarky. I’ve told you over and over that I have not used anything besides the products recommended on this forum and I’m trying to figure out the source. The same critical thinking would have me believe that whatever was there on the socket should be elsewhere, but I found no evidence of it. Not in any of the six or so other Bottlehead kits I’ve built. So I’m desperately trying to think where it may have come from. Maybe I overheated those resistors or something, I don’t know. It seems more likely than that this stuff came from the solder or iron or whatever. I was asking “might it be” the source since there is something green there with missing green parts. Doesn’t seem that outlandish. And you could have simply answered “no, that’s not possible” instead of insulting me.

Anyway, if the noise is still there, what am to do now?