The Amp Garage

Good catch! Main objective was to lower the gain a bit. Why? The power amp has much more gain than the LTP+CF combination. The windows started to rattle with the master on 1. The amp did lose its wilder side though. Local feedback made it even cleaner, which was not what I was looking for. It did b...

And the schematic minus all relais. I think this amp would benefit from a deep switch instead of a mid boost, though that is subjective. No full layout. It's 90% SSS005 though. Hi Rootz, Nice amp and thanks for the schematic. I noticed you implemented a LNFB on V1b in this amp which AFAIK was absen...

Nice!

What is this? Intrigued.

Best,

Electron

Hi Charlie, Now I am a bit confused. Is it a 10M or 1M? Best, Electron Well, six years later and I think a made a mistake with regards to one of the component values in the Tweedle Dee. :oops: After talking to Jelle a while ago and staring at my own photos I now believe that the grid leak resistor o...

Many thanks for your reply Charlie!

Indeed Ampeg amps might have been a huge inspiration for Dumble. I found this Ampeg V9 schematic and this is quite interesting.

https://el34world.com/charts/Schematics ... peg_v9.pdf

Thank you,

Electron

Dear Ampgaragists, As you all know, Dumble ODS #121 is a rare specimen. Read up on the history of #121 and you will see that it was built for Todd Sharp and that it is covered in the Dumble book. Little to no information is available, but from the little information I derived a draft for a schematic...

What components you planning on? Mostly piher resistors, a combination of el menco and Mallory brown drops and Sprague di-film caps. Some old mepco rn60e for v1 and v2 plates and old Dale 50k for v3 plates with a 5k trimmer. Cathode caps a mix of old bc Philips and new Sprague TE, cathode resistors...

And is the only possible source of this voltage whatever the user puts into the input? Yes - including scuffling across a carpet and then touching the end of the guitar cable to plug it in. Several kV is pretty common for things like that. Then there's the static electrical gradient, about 120V/met...

Really neat work! I love your rig. Once you go rack, you can never go back! First pic is with the 200w per side Class D stereo power amp, but I couldn't resist an all tube 20/20 rig in the end! The Palmer Macht does have some slam though, and I'm keeping it. Wow, that looks nice rogb! Did you tweak...

ijedouglas wrote: ↑Thu Feb 15, 2024 7:02 pm Amazing work. I just love the look of those rackmount units. Great workmanship!

Thank you for your kind words Ian!

Electron

Schematic

Fellow Ampgaragists, Forum member dbharris graciously provided me with a set of his very fine Dumbleator PCB sets. See his thread about his built: https://ampgarage.com/forum/viewtopic.php?f=4&t=36202&p=451296&hilit=Dumbleator#p451296 Apparently he still has some sets so I would encourage everyone t...

Hi Ian, fantastic build again. Do you think grounding points in this chassis have something to do with the sound of the amp? Current flows can be a strange thing. Maybe I do a PM on this. Erwin Thanks Erwin, I'm convinced of it. If you look at the attention HAD paid in his amps to the grounds as we...

Hi Eges,

I built a 002 clone without the reverb section but with an internal Dumbleator FX loop back in 2014. It sounds great.

Here is the schematic I recently upadated with the bipolar bias circuit as per Martin Manning.

Hope this helps.

Best,

Electron

Great job! I may have to try one o these :D Thanks!! I need to fix the LED location on the faceplate and it should be ready for DIY scene soon once the revisions are made. I forgot to add that I'll try an OPA2134PA op amp instead of the TL072 to see if that slight top-end loss is recovered. I know ...