Dumble Ultra P

[Smokebreak]

I've been watching these vids :
https://www.youtube.com/watch?v=GQS7nzs ... e=youtu.be
https://www.youtube.com/watch?v=ZvgV9wOzgsA

I've read every thread I can find about these amps, and there seems to be a lot of possible misinformation. I'm hoping we can have a discussion, based soley on the the overdriven tone of this specific amp, as to what the topology of this amp is, based on what we know about the D style configurations and staging.

To me, this is a fantastic sounding amp, and falls somewhere inbetween Fender/Dumble clean, and the 4 stages of an ODS type. Personally, my only experience is a D'lite, modified into a 183(kinda). But that's enough for me to have a very basic understanding of the DNA, and what these amps are capable of.

It doesn't sound, to me, like 4 stages, even with the OD "turned down". I'm not even convinced that the tone stack is after the 1st stage, but what do I know.
Yesterday, I put the Bluesmaster circuit(50K slope,22n,22n,100k mid pot) in a test bed, but left of the 4th gain stage and did some division before the PI. While I wouldn't say I'm in the ballpark, I'm in the same sport, at least.
I'm curious as to what you all think about the topology, based on what you hear, your experience, and the fact that the platform is an old Fender.

[mhartman]

Did you use the bluesmaster PI as well? If not, try that. Also, notice that it looks like they've got the channels "jumped" so you have two channels fed into the PI.

[Smokebreak]

Ah, I somehow missed the jumpering. Yes, I've got the Buesmaster PI in, but still have a standard 5K/.1 presence in from the previous amp in there. My entrance to the PI is a bit different too, to keep the PI(I think) from being a fuzz box. From the 3rd stage plate: 2n>470k//330k>2n>PI grid