The Amp Garage

Luckily for all the amp builders /electronic engineers here, the universe is electric.

Thank you Mr. Dumble.

Yes, that is the case.
Everything between 0 and 3dB is debatable.
I found a site where you can test it.
https://www.audiocheck.net/blindtests_level.php?lvl=3

Best,
Eric

I must warn you that I have never build such a circuit.
I guess if you just replace that valve for a set of MOSFET's and keep the same resistor values that the current is not that high.
-280V over 220K gives about 1.2mA / 356mW.

Merlin states that a MOSFET can be used instead of a valve in case you don't want the CF to contribute towards any tonality of its own.
Contribution towards tonality in case of the valve CF is due to clipping of the CF (top) and grid-current limiting (bottom) of the gain stage in front of the CF.

When making choices about applying VVR I guess one must take in consideration: * Where in the amp the distortion is generated (preamp/power amp) * What volume levels are required (-20dB/Bedroom level) * If tone consistency is important (PPIMV's can change tone ) * The required easy of use (how many ...

@Colossal, thanks for helping out
@Phil, a swift recovery

Looks great. Congratulations.

@alkuz1961 Yes, you are right regarding the grill cloth. This is an old picture from before I put the amp in. Currently the grill cloth is tight and does not have any waves. I might even have have put new grill cloth on. But thanks for the tip. This was my first cabinet. I learned a lot from buildin...

I have been where you are now. Indeed with a bit of routing, sanding and tolexing you will do just fine. I would pay special attention to the sanding. Take care of dents. Tolex can cover up a lot but not everything.

Thanks for cleaning up the site, Phil

Regarding the PI ground, I believe that is possible if that wire is connected to ground side the cap and resistor of the presence circuit.

I would say quiet enough on the clean channel that you could accidently forget it's on and walk away leaving it on. This has happenend. My amp is always the one with the least noise at gigs or studio. This was one of the suprises of the ODS.

Best,
Eric

Good to hear that the problem is solved. Did I read it well that this was a MOD reverb tank? I have MOD reverb tank in my Dumble clone. It took me a while to get the reverb to work. I checked the component or wiring many times but could not find the cause of having no reverb signal . In the end I ch...

It is a matter a ruling out logical sections in the circuit. Since the output of the diode bridge is only a few mV's, I would test the diode bridge in isolation first. Unsolder components at the output of the diode bridge and measure the output with respect to ground. When that is the case, the next...