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Hi all...I'm having a bit of a problem with either v1 or the high normal channel input or both. I'll try to describe the symptoms and ask questions along the way. BTW, I swapped in 4 different 12ax7's that I know are good.

1. Guitar plugged into the TMB channel with the TMB volume all the way down but the normal channel is cranked. I'm getting sound when I play, not loud/full on, but sound nonetheless.

2. Unplugging the guitar from the input causes a lot of crackling and sometimes what sounds like bad feedback. I'm guessing, but somewhere around 400 hertz.

3. When chopsticking the normal channel input I can get all kinds of hell to break loose when I touch the terminal that has all the ground points or when I touch the 1 meg resistor.

4. Chopsticking the tube socket I get problems when I touch the cathode pin of the normal channel. LOUD pops and bangs and then no sound out of the amp. Poke some more, POPOPOPOP sound comes back.

5. Jiggle the tube in the socket and it sounds like 2 and 4 above.

I have not reflowed anything yet. I did use some contact cleaner on the tube socket and the input to no avail. I'm wondering if I dont have two problems: the ground connections on the input jack and something else with V1.

Anybody have any thoughts??

Thanks
Joe G.

Generally, I try not to have thoughts - they make my head head hurt.

1 & 3 suggest your ground connection to the chasis is poor.

4 & 5 are saying you also have a bad tube socket

2 may be related to 3, or else bad connections at the input jack

HTH

_________________
Great tones come in small glass jars!

Thank you for your thoughtless suggestions

Anytime you hit a joint & it snaps, crackles or pops, it's a good be a cold joint so reflow one at a time & see.

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Thanks Coco. I'm going to re-flow the ground connection at the input jack first and then work through all the other solder joints as needed. One thing i failed to mention was that v1 is also microphonic. The tubes I swapped in were Mullard re-issues and Tung-Sols, which were not microphonic in other positions. I don't relish the idea of re-flowing the socket joints since they are so close together and difficult to get to, but I'll re-flow those as well starting with the cathode pin.

On another note, I really like the Tung-Sols in my amp. I don't find them overly bright at all. JJ's sounded very shrill to me especially in V1. What I have in the amp now are TS's in V1 and V2 and JJ ECC803s in V3. I just have not found a spot I like for the Mullard. I might try the Mullard in V3 and the JJ in V2 to see what that is like. All that being said, I'm reading more and more about cathode follower failures with most new stock tubes.
What does that actually sound like? My amp has been a bit more saggy then I prefer lately which could be related to the other issues. I'm just curious about what a tube failing in the CF position actually sounds like.

Thanks

PS
Looks like there are to Joe G.'s on this board so to avoid confusion I'll start tagging with Jersey Joe