3 Channel Fender/Dumble amp layout/ PICS ADDED

[Bob-I]

I've been thinking about this for a long time, ever since I successfully built a Dumble clone in a Crate cabinet. I have an old Allen head cabinet that's had a bunch of different project in it, now I'm going for a 3 channel head.

Since I love the old Super Reverb clean sound channel 1 will be from the AA763 ckt as will the reverb. Channel's 2 and 3 will be Dumble clean an OD.

I plan to use 2 relays, one to switch between Fender / Dumble and the other to switch between Dumble Clean and Dumble OD.

I have a Mojo bassman type OT and an AES Bassman PT, Reverb xformer and choke. I'll use metal film resistors and Orange drop PS series caps, solver mica's for 500pF and ceramic for smaller caps. Pots are all Alpha, some will be push pull for boost and other functions and there will be some mini toggles too.

Here's my layout and schematic so far. I figure I'm about 90% done so it's time to share and look for input.

I figure I'll build in sections to prevent confusion, first all the power and output sections including PI. When I'm happy with that I'll add the Fender preamp, then the Dumble and finally the reverb.

Comments are welcome.

[dobbhill]

I did a similar thing, but used a Marshall preamp on one side and a Dumble on the other. I made it so I could use the overdrive on either side. The Marshall preamp into the Dumble overdrive circuit sounds great also!!
Good luck with your project and thanks for the layout drawing.
D

[mlp-mx6]

I'm working on a layout now that will have the "just the clean side" of an ODS, switchable with "switchable ODS". My first stage is a cathode follower, to drive the 2 tone stacks more easily.

We'll see how it turns out. (of course, I MUST stop getting refinement ideas from dogears that force me to rework the layout in the computer!) (grin)

[Bob-I]

I understand the Refinements issue, this is layout #86 I think

[Robert]

Better to accomodate all of dogears suggestions before you build it. I got all my tweaks from several dogears sessions after I built mine and it looks way worse after the changes, but of course it now sounds WAY better! I used all silver mica's thinking they were better quality, which they may be, but dogears suggested all ceramic caps instead and the tone was improved. Beautiful layouts Bob.

[Bob-I]

Thx folks....

yes I've been using dogears suggestions.

[Bob-I]

I'm just getting started but I thought I'd post as I go along. This thread could last a long time..... months

[pedro]

fantastic Bob, like the idea a lot.

good luck with the build - looking forward to seeing all the pics - but above all hearing the amp.

Thx,
Pete C

[Bob-I]

More pics. I finished drilling/punching out the chassis and I'm test fitting the major components.

[Normster]

Looks awesome, Bob! That is going to be one killer amp. I take it this is the "no compromises" build.

[Bob-I]

Looks awesome, Bob! That is going to be one killer amp. I take it this is the "no compromises" build.

The only compromise is that there won't be a Marshall channel

But yes that's the plan, all the features I've come to want in an amp, the Super Reverb snap and the Dumble silkiness.

[Bob-I]

Test fitting the board, notice the bias/rectifier board installed and heaters for the 9 pins wired.

[dogears]

Looks like you are cloning a Fuchs Triple Drive! LOL.......

Congrats btw....

[Bob-I]

Looks like you are cloning a Fuchs Triple Drive! LOL.......

Congrats btw....

really? I've never actually looked at this amp. Any advise?