trinityamps.com

Just finished my first amp build, and it was so fun and it sounds pretty good! But it’s developed a problem. It has a static when pushed that I think is a tube, but don’t know. So I figured why not ask the people most familiar with this. i made a video: https://youtu.be/va8RrmrJ3xo

Anyone recognize that sound?

Sounds like it could be a tube. See if you can duplicate the sound by tapping on each one with a wooden chopstick.

I did tap on all the tubes and with the power tubes I could kinda hear through the speaker the tapping. Swapped the preamp tubes for known good tubes and no change. Think that means it’s the power tubes?

One thing I noticed when firing it up one time: one of the power tubes flared up very bright, then went to normal, and stayed normal-looking after that.

Update:

Changing tubes made no difference.

But I’ve noticed that if I push against the chassis, it can make it go away. Sounds like a grounding issue?

Update:

Removing the back panel seems to make sound go away, so I’m guessing it’s the cabinet rattling against the chassis. Am going to try some weather stripping on the inside of the panel and see if that solves it.

I had a problem with the back panel rattling a bit on my Tweed. I fixed it by added another screw to secure the back panel to the chassis in the middle. Weatherstripping should work too, as long as it doesn't get too hot.

Thin rear panel tweed cabs (our including ours) can rattle. Our chassis have tapped holes in them so a 4-40 screw can be used to tihghten them down. That sounded like an electrical issue though. Loose connection or one where you forgot to solder!

Cell phones are problematic too!!

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

Thanks and I think you are right. Weather stripping did kinda help, but I think a vibration is making a solder joint vibrate. I’m gonna go through and check it and reflow some solder. Thanks!

UPDATE:

Sorry for being gone for a while and not posting my findings! Short story is I fixed the problem and I got lost playing it so much that I forgot to come back and update.

Long story: I opened it after playing it a while, looking for anything vibrating. My issues were a staticky sound coming from the speaker when biting a G anywhere in the fret board, and the knobs seem to cut signal when cranked past 10 or so.

The first issue I couldn’t find until I pull the whole circuit board out again. I decided I needed to reflow solder on each joint, but noticed that as soon as I lifted the board, the ground wire came loose will almost no effort. Bingo. Resoldered it and I think that was the problem. Also I had used some odd nuts to hold the board in place, so I removed those too, just in case.

I then looked at the connections between the pots and noticed two were touching after I pushed the board back in place. Using wooden chopsticks I moved them around until I heard the least amount of hum and the knobs worked perfectly.

It’s now my favorite amp and has completely shifted my tastes in gain. I love it. THANK YOU TRINITY AMPS