Dumble modded bassman on ebay

[ToneMerc]

Speaking of hand picked parts since this was done in 96-97 this would be post grail era which tells us those parts were tweeked and tweezed well before that era saved by Dumble and chosen for that sound.

These additional parts are typical of parts found in 90's builds, nothing spectacular here. I can go to my local parts shop and pull the same parts. There are NTE flameproof plates resistors, Sprague 715, 716 and there might be a 6PS cap in there.

TM

[qtone]

Hmm so just another nothing special Dumble one off then ?

[stevlech]

Qtone- you have some experience with a similar amp, don't you?

[Cameron]

Anyone notice it has 4 preamp valves.

Aaron

Nothing ODS about it. Looks more like a Naylor type preamp.
One for the pi. One for the fender ch. Two for the Marshall(Naylor) ch.

[jon]

So guys as a birthday treat Jelle built me the high gain side of this amp. It was a great night of soldering and listening to Katy Perry.

All kidding asside this is the smoothest high gain monster I have ever been exposed to.

[qtone]

Qtone- you have some experience with a similar amp, don't you?

"OH FUNNY" in my best Pacino voice.

About 5 months worth yes im here all week.
And dont even get me started on #5.

The stories I could tell there..

[10thTx]

Will edit a schematic and repost.

[stevlech]

Thank you 10th Tx. You are quite prolific with schemes around here and on Hoffman's forum.

I believe the first channel is actually much simpler in that it is a 3 stages + cathode follower + tonestack arrangement like a JCM 800. Maybe this is the origin of the Ripper???

[10thTx]

the first channel is actually much simpler in that it is a 3 stages + cathode follower + tonestack arrangement like a JCM 800.

I think you're right. Thanks!

Maybe something like this? OR instead of an OD stage, an active FX?

Thoughts? This would at least account for the four 12A_7 tubes.

With respect, 10thtx

[stevlech]

I believe that the first channel looks something like this (values in red are purely speculation):

[stevlech]

Oh, and the PI is Marshall all the way w/o a Presence control.

[Cameron]

the first channel is actually much simpler in that it is a 3 stages + cathode follower + tonestack arrangement like a JCM 800.

I think you're right. Thanks!

Maybe something like this? OR instead of an OD stage, an active FX?

Thoughts? This would at least account for the four 12A_7 tubes.

With respect, 10thtx

I think you are forgetting ...it still has the other channel. No extra gain or loop.

[10thTx]

I think you are forgetting ...it still has the other channel. No extra gain or loop.

What !!!! Gee whiz, that's not nearly as interesting.

Do you mean that this incredibly brilliant innovative extraordinary and perhaps eccentric man who is shrouded in mystery and folklore of legendary proportions only did something kinda sorta quasi interesting?



Sounds like it's a sorta JCM800 topology with Dumble component values with another channel with fenderish(?) topology.

Oh well! With respect, 10thtx

[CHIP]

I don't see a mid pot on the front panel, The schematic guesses on this page shows a mid pot. Is the mid pot on the back of the amp?

Sorry, I see that he stuck a pot in the input jack hole.

[ToneMerc]

Oh, and the PI is Marshall all the way w/o a Presence control.

No, the PI is Fender 5F6A which is the Marshall PI.

TM