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previous: Nils Hi,If I remember ri... -- 6/22/1999 12:12 PM

Re: Dumble

6/23/1999 2:49 AM
Paul C	Re: Dumble I built one for a guy last month out of a boogie clone made by some guy named Decker. One "trick" I did ( is this allowed with a dumble?) is with the volume control. The clean channel breaks up so quick it really needs a master volume, but the preamp really doesn't break up. I stuck a MV on the inv side of the relay and noticed that at low MV settings the amp was clean even with the preamp volume dimed. That feedback loop reduces the gain and also the 2nd stage from clipping. But it seems that the different levels of feedback you get from the loading from the volume pot makes the taper feel strange. So we just took the preamp volume out of the circuit. The treble control wiper goes into the 220k series resistor and into the grid - no 1M to ground. So now it's an amp with a MV but no preamp volume!! Then we stuck in a verb circuit sort of like a fender...

6/23/1999 2:49 AM

Paul C

Re: Dumble

I built one for a guy last month out of a boogie clone made by some guy named Decker. One "trick" I did ( is this allowed with a dumble?) is with the volume control. The clean channel breaks up so quick it really needs a master volume, but the preamp really doesn't break up. I stuck a MV on the inv side of the relay and noticed that at low MV settings the amp was clean even with the preamp volume dimed. That feedback loop reduces the gain and also the 2nd stage from clipping. But it seems that the different levels of feedback you get from the loading from the volume pot makes the taper feel strange. So we just took the preamp volume out of the circuit. The treble control wiper goes into the 220k series resistor and into the grid - no 1M to ground. So now it's an amp with a MV but no preamp volume!! Then we stuck in a verb circuit sort of like a fender...

Replies:

Dave Chun Paul -Do you mean the *over... -- 6/23/1999 3:59 AM
Mook "Jazz" switch -- 7/2/1999 8:20 PM