Pimp my Electar/Beast my Champ

[Bear]

I've got a stock Electar Tube 10 begging to be improved. 5881, 12ax7, SS rectified, TMB, gain and volume controls. Not the worst thing I've ever heard. Can be borderline okay through an external cab. But it's time to make it sound good. Making it sound less congested, less hard and pinched in the mids, and with a less farty bass response is the general idea. I'm planning on just using it as a head to my TL-806 cab with an EVM-12L, so I don't care about speaker upgrades for now.

The anemic little OT will be yanked, maybe to be reused if I want to do a 5F1 with a 6aq5 at low volts down the road. For these SE jobs, is there such a thing as too much OT? Or is there a sweet spot for matching the transformer to the rest of the circuit to get some saturation?

The Beast circuit is a pretty obvious starting point. Just a rawk amp or does it clean up well? How does it take pedals? Other ideas?

[Phil_S]

The anemic little OT will be yanked, maybe to be reused if I want to do a 5F1 with a 6aq5 at low volts down the road. For these SE jobs, is there such a thing as too much OT? Or is there a sweet spot for matching the transformer to the rest of the circuit to get some saturation?

The conventional wisdom seems to be that you can't have too much iron, though I've got a PT from an organ with a 6.3V 9A winding and you'd need a roadie to cart it around. Aside from practical limitations like size and weight, the conventional wisdom generally holds up. I suspect, however that you are right about the saturation issue. A big OT might sound good, but may not produce the tone you are looking for.

I can't imagine the one you are harvesting from the Tube 10 is that big. If the turns ratio is appropriate, I'd sure give it a try. You probably know, you can "adjust" the primary impedance by your choice of speaker impedance.

BTW, 6AQ5 is probably my favorite tube. I've got about 50 of them from when I went on an acquisition binge. I think my average cost per tube is probably in the $3 range, maybe less. Yeah, I got a few losers, but the winners are wonderful. I think the best ones turned out to be Sylvania, which I put in a TW Express deviant and they biased better than new tubes. I've got them running with plate voltage in the 330s. I don't use the amp that much, so I don't know for sure about longevity at that voltage, but what the heck, you only live once. I don't think it's a problem at all to run the 6AQ5 in the 300-310v range. I know what the spec sheet says, and depending on which brand, it's 250V or I think it's Tung Sol that says 275V.

[sliberty]

I'd try to fine a place to add a second 9 pin tube, and go with an AC4 preamp against that octal power tube.

[Bear]

There's a nice spot next to V1 where there's a preamp out jack and plenty of territory for putting in a fresh socket. I've seen pics of someone's mod doing just this.

I was thinking more a top-boost/Rocket type pre if doing something with two preamp tubes. Can't decide where would be a good place to wiggle the bias with the spare triode, so probably use the spare for a paralleled front end. EF-86, tone switching, one half of the 12ax7 to give a bit more push, with the other half wiggling the first, and then the power amp -- that might work. As long as V1 would be in a new socket, an octal 6SJ7 pentode would be a cheaper entry into that sort of feel.

Alternate idea with an extra socket would be a Vibrochamp with an improved and/or simpler tone stack.

Hmm. I think maybe I should aim clean(ish) and not worry about OT saturation. I use pedals, including plenty of dirt flavors, and I only play at home these days. Which is moving me towards tuning this for a 6V6 -- yeah, volume differences aren't huge, but a bit less is good.