Tube Amp Archive

Are all the front pots grounded through the front-face of the chassis? I saw some old post by Carmeron I've seem to neglect/not notice.... Still have the noise on both units, but are shipping off the original 88 to the Finnish tech when he gets back to me about payment options and shipment. Clone do...

Okey, so I think I figured out the real issue of the noise on the GP-1000. The signal goes way too close to the power section at several places. I moved some cables a few inches more away, and now there is no noise on the pot, however, it is still present underlying, however I've read that all amps ...

Yeah, all originals has their at the input socket.My clone didn't have any at all, but adding didn't do any. So the amp is broken stock then? Must be some of the worst mistakes a company can do. Anyways, what do you want picture of? There is large full amp pictures of original and clone in this thre...

My 88 behaves exactly the same way as the clone. The more I turn up the level trimpot the more noise. I think it is linear in my clone thought, because the noise is present on every setting except the very minimal one (still there but bearly audible). Now gorhruts original was noise free on that con...

It could generate hum, but I've never experimented that it has too much hum to handle, and at least not with EMG mics. You could try to sheild everything better, but my guess is that this is an amp issue. I mean does other amps sound the same with the guitar? Are all grids sheilded? Are any V1,2 and...

So I've tried installing a grid stopper and rewiring C4 between the two masters instead at 2 EQ switch, and nothing got better or worse. Still same old story. There must be some issue with the overall design... and yes possiby a ground issue. It is like the signal is partly being fed to ground, that...

No won't take it to a tech for several reasons; 1. It is no guitar techs or guys at the instrument stores with knowleadge for about 60 metric miles. 2. In Norway that kind of stuff is very very expensive. Even minor stuff. Like $2-300. 3. It is my signature amp with my name on it, built by a friend ...

It is not on my tube socket, checked 4 times, no resistor there at all except the two ground resistors (R201/R202). No grid stopper at all. On the last stage...Gorhrut fixed it without touching much of the last stage.... Did the exact same thing as him... And no this is not going to a tech, if I can...

So you think it is a ground issue when the grid stopper isn't there at all and it is eliminated with low master volume or treble also distortion tames it. Would have to be related to V1 then or input.... Also Gorhrut had it eliminated in his original state amp and have now a very simple grouding sol...

Okay, decided that I could test it with a 33k grid stopper, have some around from my unused JE-1000 clones. Or could run two in series, but would increase the chances of shorts, and I've read that 33k could be enough to prevent noise even on high gain. Also read that low gain amps that have good inp...

It's a very weird thing to leave out and I'm 100% sure it is not there, so really really weird... Yeah that could be my whole problem right there. Also seems like he switched the position of R202 and R204, but can't be sure without doing some readings with my multimeter. Can't read the stripes on th...

Double and triple checked today, R101 the 68k resistor going to tube is missing, it is not on the back input either, so it was left out. I don't know if it is something that could create noise, but worth checking. Also... the whole TUBE PCB is kind of messy on the clone...Especially around V2, seems...

Looks great and easily modified! Some wring yet, but a lot better than the original. I still crave double masters thought. You know what I can't for the life of me find R101 (input resistor) on the clone! He might have hid it underneath some pcb at the back input. But if it isn't that would be a maj...

Tried several GT sets also with 12au7s and also a EH set. No difference, EH et actually made it worse due to a faulty tube. Also there is no noise present when you mute the guitar/strings and it happens on all my 9 guitars with 5 different pickups/hookup methods. It is not the tubes and not the guit...

Okay, so I tried rewiring the pot and simply remove the pot from the circuit just connecting the masters to C4, and the problem is still there. It is like a screeching frequency that totally overdubs the guitar sound, what I posted before was at the lowest possible noise setting at low trimpot level...