Simple 6L6 PP Guitar Design Needed

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Hi Guys,

Im Looking for a Simple Schematic,

I just acquired a few vintage parts in great working order I would Like to use in a simple 6L6 PP power amp for guitar use.

PT is rather heavy duty as it was used to run 7-12AX7s,28 12FQ8's and a 5U4 rect. So power should be in ample supply.
The OPT transformer was matched to this unit driven by 2 6L6GC's and output was into 2- 12" vintage instrument speakers.
All donors from a 1959 wurlitzer organ.
The speakers will of course not be re-used.

My current supply of tubes is fairly wide so im not limited to only 12AX7's as drivers, Though it would most likely add to simplicity.

I have several preamp designs that produce tonal qualities I prefer, But I am looking for a bit more power over the practice amps I have recently built.

I would prefer something that is in the KISS league (Keep It Simple Stupid) as I am not a newbie, but no expert either.
Gene
 
There are sevferal very similar old Fender amps that use a pair of 6L6 and a pretty simple front end:

Pro 5E5
Super 5D4 or 5E4
Bandmaster 5E7
Bassman 5F6

Each of these uses two or three 12AX7 or in some cases 12AY7.

In fact, if all you are using is the tranformers and parts, you can buy ready made chassis, drilled and labelled for the models I listed. Cabs too for that matter.

The 5E5 and similar numbers are specific versions fo these amps. LAter versions got more complex, like adding tremolo and/or reverb. SOme of these have two input channels, and one could be eliminated to make it even more simple. SO I recommend looking into those specific schematics first. The differences between the models is not spacious. FInd one of them and you get the idea.

You can also get a lot of helpful discussion about it over at www.ampage.org
 
PP 6L6 guitar amp designs are...

...everywhere.

There were lots and lots of push pull 6L6 amps made. All kinds. Ampeg, Fender, Gibson, Epiphone, Mesa Boogie, Traynor, and all sorts of other obscure brands.

I went through a phase of building a lot of different guitar amp circuits into a chassis, to try out how each one 'sounded.' My conclusion was that the power amp section doesn't make all that much difference, but the preamp/tone control section sure does. Each tone 'stack' has its own tonal character, and they're very different.

My personal favorite is the mid-1960s 'Blackface' Fender Vibrolux-style power amp circuit. It has a 12AT7 long-tailed pair (Schmitt) phase splitter/driver, with a bit of negative feedback from the output transformer secondary to the tail of the LTP. The tone control circuit has that 'Fender' sound, but you can substitute any you like, so long as you match the gain to the input sensitivity of the output stage.

Duncan's Tone Stack Calculator is fun to play with:
TSC

You can see how the different tone control circuits affect the frequency response as you adjust their controls. It's pretty cool.

Finally, I think the single biggest factor in getting a sound you like is the speaker cab (of course). I like smallish speakers in big, open back cabs (for guitar). I like the sound of a large baffle area for electric guitar, but I hate the sound of a large speaker on a small baffle (like in a Mesa Boogie amp).
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