Tube Amp Archive

Thank you Erwin for your help. i think i found the problem, its on pin 8 of V2 i can measure 150hz on the 0,22uf LNFB cap and on CX02 0,01uf. And from there its in the signal chain. I will now check the tube and components. Hi Christopher, you mentioned in your initial post that opening your first ...

Thank you Erwin for your help.

i think i found the problem, its on pin 8 of V2 i can measure 150hz on the 0,22uf LNFB cap and on CX02 0,01uf. And from there its in the signal chain. I will now check the tube and components.

So yesterday i tried to find the noise with my scope but around V1 i see nothing, the B+ supply after the plate resistor also looks good. Of course my scope is an relatively cheap USB Scope (I can only measure up to 400v with a x10 probe) and little artifacts are always there but with a 1000hz 150mv...

I can't realy see how the cap can is connected and how it is grounded. Can you make a drawing of the wiring? The cap can is grounded on the Lug Strip, the can has one negative pole, and there is a black wire that goes to the lug strip. Hard to see of course. The rest is as on the plan of Ryan. And ...

The hum is still there but the noise floor generally lowered around 3db (same settings on the volume pots). Because of the hissing at around 3000hz the hum is not perceived as such. :? I attached the soundfile, high filter first and low filter second. The FET-Board was still disconnected. Tomorrow i...

I rerouted some grounding wires and reflowed everything around V1 and some other components, i also checked the grounding of all metalparts, indeed there was a problem with the high filter switch. I temporally added caps in parallel on the Cap can. I disconnected the FET-Board also. Nothing changed ...

The 1M resistor is there, it is directly on the input jack. It is also an RN65 so the color is nearly the same as the jack itself, it is behind the blue cable. The yellow wire doesn't react to chop-sticking, generally i didn't find anything that reacted to my chopstick for now :lol: But i will chang...

Hello and thanks for your response. :D I already scraped all ground points and used lock washer while building the amp. All groundpoints measure great. The Input jack is isolated and i already test it by having the jack floating freely, but nothing changed. I have now replaced the input-jack cable w...

Hello everyone, this is my first post but I've been reading the forum a lot since i bought the SSS Chassis and PCB's from Erwin. I completed my SSS Build last year incl. scope PI-Balance etc. The amp sounds amazing and i really like him but i have one problem, i got some noise/buzzing. The noise goe...