Rocket Problems

[Littlewyan]

Where are the pots currently grounded?

AH yes your volume pot does look like its wired up a bit strangely. Is the ground connected on the right hand side? I can't see any wire going to the left hand lug.

[JoshBernstein]

The pots are currently grounded with the preamp, which is also grounded with the power amp. The left hand lug is connected, but the wire is hidden behind the bright cap. Ive just reversed the 2 outer connections, with the right hand lug grounded instead of the left hand one.

[Littlewyan]

Can you upload another photo? If the red wire that was attached to the pot was the ground then it was wired correctly already I think.

Leave the pot grounded with the pre amp for now.

[JoshBernstein]

Couldnt get an updated picture tonight, ill get one tomorrow. But ive moved the preamp ground to the input jack, as well as the ground for the pots. Still no change.
Littlewyan,
Thank you for your help so far, and i appreciate you following my thread

[JoshBernstein]

Do you think it could be coming in through the power supply?
Is there anything i can do to see if its coming in that way? I may end up just having to buy a crappy pc based o scope because im going nuts

[Littlewyan]

I'm really not sure at the moment if I'm honest and I have to admit I only heard the noise in your video where you palm muted the notes. I wasn't wearing headphones though.

Have you tried taking the amp off of the speaker cabinet? And are you definitely sure its coming from the speakers? As I had a strange noise coming from my Express once after I changed the OT and it turned out to be a bit of loose metal inside the OT. That was a ringing noise. Once I had the amp at practice volume I couldn't hear it and after a while it stopped doing it anyway.

[JoshBernstein]

Well at this point, its been few months since i completed the build the first time, and im starting to think im just gonna have to live with it. Tonight ill try taking it off the cab and playing it in a different room. Maybe outside to at gig volume and see how it does. It may just not be a practice amp.
It really does seem to be coming from the speakers though. And the thing that bugs me is that it continues the ringing after the regular note is no longer audible.

[Littlewyan]

I'm not sure what else to suggest at the moment. You say you replaced all of the capacitors and resistors?

I don't think its oscillation as it doesn't change whether its clean or distorted.

[JoshBernstein]

Im starting to think the same thing. Im going to try adding some large grid stoppers in the preamp, and maybe some caps accross plate resistors to try and narrow down where it's coming from.
And yell, all resistors and caps were changed.

[Littlewyan]

No I said I don't think its Oscillation. You can try grid stoppers but I can't see them helping personally. If it was oscillation it would normally get worse as you increased the volume. This ringing stays pretty constant no matter where the controls are set.

Is the ringing in tune with the note you're playing?

[JoshBernstein]

Sorry, i misread it, my mistake. It is out of tune with the note being played. Some notes seem more out of tune than others.

[JoshBernstein]

Ive read about similar issues with other amps, and with other amps similar problems seem to be caused by inadequate filtering. I cant imagine that being the problem with the power amp, as it has 80uf for the plate and 40 for the screens, but ill try adding some more filtering and see if there is an improvement.

[Littlewyan]

It won't be a lack of filtering, that is plenty. My Marshall JTM50 runs on less than that! I've only got 32uF for my mains and I have no issues with ghost notes or anything.

[BLT]

If the photo has any bearing on your amp as it stands right now, I would redo your preamp board. Your orientation gives me a headache just looking at it. The one end of your mains filter cap needs a terminal strip, and I'd try to figure a way of getting a GZ34 in there instead of solid state. If you have a meter, it would be nice to see voltages.

[JoshBernstein]

I may end up redoing the board, and i will definitely secure the filter cap. And i orginially built it in a different chassis with a gz34, but didnt like it. All of the amps ive owned so far have been ss rectified, and i guess i like the tighter sound they provide. I know most people prefer the tube rectification, but i still like the diodes.
But i finally solved the problem, which ended up being the v1 cathode cap. Removed it and the problem disappeared.
Thank you for the help and suggestions. Also thanks to littlewyan, who helped helped me and followed the thread the entire time. Its greatly appreciated.
I will go back and add the rubber grommets and, as well as the clamp/terminal strip for the cap that is currently unsupported. Thanks again!