Maybe an amp with cathode biased EL34s and no NFB

I’m thinking about my next project which will be putting something with vacuum tubes inside the Crate SS head I bought a few months ago at a thrift store. This Crate GT1200H costs me 25 bucks an actually worked perfectly but it needs tubes….

I’m going to try and do an amp that has a pair of push pull EL34s and no negative feedback. From my searching around I haven’t found too many examples of amps with this configuration.
There are the Matchless Clubman and Chieftain and I’ve also heard of some people basically using EL34s in an 18 watt lite design. Thats about all I have come across.

While working on another amp I briefly tried the 18 watt lite configuration with EL34s and while it sounded good I don’t believe a single triode and an LTP PI was enough to really drive a pair of EL34s. I had to turn up the volume more than I would have expected.

So I’ve been thinking about possible designs and I think I’ve settled on something loosely based on a Fender 6G3 Deluxe preamp but with added tone control options. It will have treble, middle and bass but not in a conventional tone stack. Each will be separate and in different parts of the circuit (somewhat like Matchless Clubman and Chieftain). By doing it this way I hope to not loose so much gain but at the same time have a wide variety of ways to dial in the amp. The Fender 6G3 does have a bit of NFB but I’m going to try without. I’ll probably use a cut control in the output section which is something that I I believe helps Matchless get away with no NFB in it’s EL34 based amps.

I think I’ll also include an effects loop, mostly for adding reverb.

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