Whats on your amp workbench?

[StrummersOfThunder]

Itrs a shame we didnt video this simple mod for you tube / glad better living / the courts.

I could swear someone was filming. Or maybe just your hidden cameras in the ceiling

The whole situation had a Japanese gameshow vibe.

The obstacle course and the genital shaming?

[robthemac]

I could swear someone was filming. Or maybe just your hidden cameras in the ceiling

The whole situation had a Japanese gameshow vibe.

The obstacle course and the genital shaming?

And fifteen giggling Japanese schoolgirls

[Bg]

If in doubt, give it a clout.

In other outside of the box news, I just removed a door handle set with a hacksaw.

[jeremyb]

I've seen a few paintless dent removal videos on youtube, maybe another hobby I could entertain to add to the overwhelming list of ones I already do but don't do.

[StrummersOfThunder]

The whole situation had a Japanese gameshow vibe.

The obstacle course and the genital shaming?

And fifteen giggling Japanese schoolgirls

The general theme of your pedal enclosures as far as I’ve seen

[Bg]

IMG_2018.jpeg (3.82 MiB) Viewed 755 times

Here we go, I really dig this djw, but also wanted it in a headshell. It'll be removable.

Work in progress

[murky]

Upgraded to a Fryette ZMACS amp switcher - 4 amps/4 cabs. Should come with a warning not to casually dismiss how many cables you’re going to need…..

IMG_0609.jpeg (4.55 MiB) Viewed 532 times

And that’s just for the ZMACS - probably another 8-9 required for the rest of the rig and Cyclops.

[Cdog]

Upgraded to a Fryette ZMACS amp switcher - 4 amps/4 cabs. Should come with a warning not to casually dismiss how many cables you’re going to need…..

IMG_0609.jpeg

And that’s just for the ZMACS - probably another 8-9 required for the rest of the rig and Cyclops.

That's hard core! This in your studio?

[murky]

Upgraded to a Fryette ZMACS amp switcher - 4 amps/4 cabs. Should come with a warning not to casually dismiss how many cables you’re going to need…..

IMG_0609.jpeg

And that’s just for the ZMACS - probably another 8-9 required for the rest of the rig and Cyclops.

That's hard core! This in your studio?

Nah, studio implies talent. Just a room where good amps go to be tortured….

[MikeC]

Upgraded to a Fryette ZMACS amp switcher - 4 amps/4 cabs. Should come with a warning not to casually dismiss how many cables you’re going to need…..

IMG_0609.jpeg

And that’s just for the ZMACS - probably another 8-9 required for the rest of the rig and Cyclops.

That's hard core! This in your studio?

Nah, studio implies talent. Just a room where good amps go to be tortured….

Send them to me when they're permanently unconscious.

[jeremyb]

Upgraded to a Fryette ZMACS amp switcher - 4 amps/4 cabs. Should come with a warning not to casually dismiss how many cables you’re going to need…..

IMG_0609.jpeg

And that’s just for the ZMACS - probably another 8-9 required for the rest of the rig and Cyclops.

That's hard core! This in your studio?

Nah, studio implies talent. Just a room where good amps go to be tortured….

We don't call it torture, its advanced interrogation!

[WellyBlues]

Upgraded to a Fryette ZMACS amp switcher - 4 amps/4 cabs. Should come with a warning not to casually dismiss how many cables you’re going to need…..

IMG_0609.jpeg

And that’s just for the ZMACS - probably another 8-9 required for the rest of the rig and Cyclops.

That's hard core! This in your studio?

Nah, studio implies talent. Just a room where good amps go to be tortured….

It would be Trial by Ordeal for both amps and listeners in my case!!

[Jay]

I think the northern lights have been captured in your toobz!

I don't think I have seen such a bad example. I wonder how the bias can drift so much to cause this. Any suggestions welcome

I don’t think drift can do that. It’d have to be a serious failure somewhere that’s messing up the bias.

Is it cathode biased? If so, the cathode bypass cap may be shorted. If it’s grid biased, something is messing with the negative bias supply- maybe a bad cap. Or else one of the 6V6s has a short from anode (or screen) to cathode or grid, which could then mess up biasing on both tubes.

Well, finally back at this and figured out what is causing the red plating but don't understand if it is bad amp design or a failed component somewhere.

Here goes... the grid bias I set to -49vdc. Trem depth pot fully turned counterclockwise. Switch trem on via push/pull knob.
Bias still at -49vdc, no trem sound.

Turn knob a quarter clockwise, nice trem sound coming thru, bias swings between -49 and roughly -45vdc.

Turn depth knob full clockwise, trem sound fine, bias swings between -49 and -39vdc. No RED plating.

Now turn trem switch to OFF but leave depth knob as is. Bias should return to -49vdc but it doesn't, it stays at -39vdc and the plates are turning RED.

Turn the depth know knob fully counhter clockwise and bias goes back to normal and no red plating.

So I thought one of the 0.1uF caps is leaking (circled in red on photo) and replaced them with new ones. No change.

Now the plate voltages are huge at idle being 485vdc and the 6L6 spec says for class AB its max voltage is 360vdc. So perhaps bring those down?

Any recommendation for next step to test?

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[jeremyb]

I hope you have all your shots up to date, I caught tetanus just looking at the photo!

[MikeC]

Are you measuring bias on the 6L6 grid?
Also, EH 6L6 specs state 500V max on plates? It's not 6V6 is it?
Is it just biased too hot to deal with the lowered bias voltage that occurs with the trem settings as described.
Have you calculated the % of MPD at idle - can you lower this?