18Watt.com

That resistance is probably negligible and it’s also very likely not an accurate thing IMHO
The 6N2P-EV is not the cause of any serious voltage difference. I always use those and they have given me absolutely no trouble at all. On the contrary.. they just deliver, every single one

chaliapin wrote: ↑

Sat 09/23/23 5:10 am

I have 100uf to hand but nothing larger, will that be any improvement?

It might help a little. I think you need to go to 2200µF though.

Well the always on ups reduces rubbish from washing machine and electric fencer but still angry noise at full power and volume up to 6, guitar on full. Patched over the vvr, no change.

Mostly sounds good on lower power, no nasty noises.

Another highlighter test revealed nothing, several caps do not have the values marked on them. I could take them out and test them but I did test them before installing. Would I see a problem in the voltages if there was a problem here?

Could be the power tubes, I haven't got alternatives yet. However with the pp-se mod I can use 2 at a time. Switching them round does nothing, seems unlikely more than once is bad?

I also have done nothing concerning the jj rectifier tube. Could this be failing to supply enough juice when asked to although appearing to work fine the rest of the time.

chaliapin wrote: ↑

Sun 10/01/23 7:55 am

I also have done nothing concerning the jj rectifier tube. Could this be failing to supply enough juice when asked to although appearing to work fine the rest of the time.

just delete that tube. It's nothing but trouble and zero to be gained. Go SS on this amp..

I was going to add protection diodes, would that be enough?

chaliapin wrote: ↑

Mon 10/02/23 3:06 am

I was going to add protection diodes, would that be enough?

They won't reach the B+. You have to tie them together. Better take 2x 2 diodes in series and join them at the A-node or standby switch. it's a 2 minute job

Or if you have the space you can add a switch to choose between SS and tube rectification.It goes without saying that this switch should be a decent one with good power handling, not the mini switch type of thing. And never switch with the power on!

Thanks, I have a single switch 240vac rated. What about rob's version?

https://robrobinette.com/Generic_Tube_A ... ier_Switch

chaliapin wrote: ↑

Mon 10/02/23 4:39 am

Thanks, I have a single switch 240vac rated. What about rob's version?

https://robrobinette.com/Generic_Tube_A ... ier_Switch

that's ok too, but mine is safer. On Rob's you are going to switch the DC voltage, which is a lot higher and DC is more dangerous and hard on the switch. But hey, the standby switch is done this way too, so go ahead. But also know that a DPDT switch on the AC side of the HT winding, switching the 2 HT wires at once is also a safer way. Same deal for the HT fuse.. better 2 fuses, one on each wire. There's been a lot of discussion about this, but that is my conclusion.

Bieworm wrote: ↑

Mon 10/02/23 4:13 am

Or if you have the space you can add a switch to choose between SS and tube rectification.It goes without saying that this switch should be a decent one with good power handling, not the mini switch type of thing. And never switch with the power on!

Or you can do it my way. Replace the Standby switch with a DPDT On-OFF-On switch. Standby is the middle position, then tube or ss rec on one of the other two positions. No extra switches needed.

SS rec is better though. The tube rectifier doesn't do anything for your amp tone. Sag resistors take care of the sag if somebody cares about that.

Put in the ss switch as per rob as I had the parts. B plus up but no improvement in sound. Bypass caps are now 100uf made no difference.

Did my highlighter test, found nothing but I'm unable to verify a few caps as they are not marked with values.

The 5n cap I think is the coupling cap after v1 before the volume and tone and the 5n going to ground from the volume and tone. I also couldn't verify the coupling caps to the power section but I replaced those previously and verified them on the meter before installing. Should I remove the 5n caps and test? I would have tested before installing originally.

Start over, this thread has gotten cuckoo.

Post NEW voltages, and NEW photos of the build in its current state.

Post a schematic that's accurate to your current setup; if you've changed something, notate that on the schematic.

I think you may need to improve your filter caps, and you should definitely try a 2200uF cathode cap. You also need to try new tubes to rule the tubes out, speculating doesn't help.