...when I turn the amp from standby to ON. Hum goes away when I pull out the rectifier tube. I've tried different rectifiers and it doesn't matter. Even swapped out all my tubes one by one, as well as replaced every component of the LTP one by one, and every component of the power supply one by one. I can sort of play through the amp, but the hum and another LOUD abrasive noise will not stop. Also have one output tube redplating. Any ideas?
thanks!
MASSIVE hum...
Moderators: pompeiisneaks, Colossal
Re: MASSIVE hum...
Is this a new build, or is this an amp that had been working properly?
Wife: How many amps do you need?
Me: Just one more...
Me: Just one more...
Re: MASSIVE hum...
this is a new build. It's a 6v6-powered plexi-ish/Lightning-ish circuit, with a few of my own tweeks.
Been at this for a couple of days, and I ended up getting a few suggestions at 18Watt(yep, finally able to log in -- problem was on my computer). I've actually made some progress:
1) underneath the board there was a frozen drip of solder from one of the turrets in the power supply that was just that close to one of the OT's mounting bolts. It was arcing.
2) I had one 6v6 redplating a little bit. Turns out the socket's cathode pin was pretty loose. Ended up replacing both output sockets. No more redplating. The other one had a very loose pin #5.
3) I think I've narrowed the hum down to the PI. I was chopsticking and the hum went away, but it's still intermittent. I took the chassis off the cab and placed it next to the cab. Seems the vibration was helping to set it off. I'm gonna replace that socket and rewire the PI.
In the process of trying to locate the problem, I ended up replacing nearly every component from the PI through the power supply, as well as an OT. But I'm still proud of this build and I can't wait til all the bugs are fixed. This thing sounds pretty amazing. Reminds me a little of an Express and a Studio .22 -- really. I'll have to post clips when I'm finished. I am a little bit bummed that the build doesn't look as nice as it had started out. I made a really big effort to build this as cleanly and pro as I could, but some of that has suffered due to all of the parts-swapping. Oh well, live and learn...
Been at this for a couple of days, and I ended up getting a few suggestions at 18Watt(yep, finally able to log in -- problem was on my computer). I've actually made some progress:
1) underneath the board there was a frozen drip of solder from one of the turrets in the power supply that was just that close to one of the OT's mounting bolts. It was arcing.
2) I had one 6v6 redplating a little bit. Turns out the socket's cathode pin was pretty loose. Ended up replacing both output sockets. No more redplating. The other one had a very loose pin #5.
3) I think I've narrowed the hum down to the PI. I was chopsticking and the hum went away, but it's still intermittent. I took the chassis off the cab and placed it next to the cab. Seems the vibration was helping to set it off. I'm gonna replace that socket and rewire the PI.
In the process of trying to locate the problem, I ended up replacing nearly every component from the PI through the power supply, as well as an OT. But I'm still proud of this build and I can't wait til all the bugs are fixed. This thing sounds pretty amazing. Reminds me a little of an Express and a Studio .22 -- really. I'll have to post clips when I'm finished. I am a little bit bummed that the build doesn't look as nice as it had started out. I made a really big effort to build this as cleanly and pro as I could, but some of that has suffered due to all of the parts-swapping. Oh well, live and learn...