Tweed Super questions

[Mark Buckingham]

So, I've got a chassis and cabinet for a tweed super coming my way (thanks Bruce)...

I already have a OT & PT from Weber that can handle a pair of 6v6's (made for a Deluxe Reverb)... (680 or 540 VAC / 150 ma.)

I'd like to avoid buying another transformer set, so I'm trying to figure out exactly how much I'd be giving up by using the transformers I have... Otherwise, I'll have to buy another set.

I'm not gigging right now... Not even in a band anymore, but if I had to, I have a 50 watt SLO clone that would be loud enough for that sort of thing.

Would the 6L6's have that much more oomph to them, or even better, could I get away with the 6L6's with the transformers I already have?

Would I get more headroom out of the 6V6's if I moved away from the cathodyne inverter and went to a long tailed pair? I already have a princeton reverb, so I do want to have more headroom than that...

Thanks!

[Arthur B.]

I don't know about switching between 6v6 and 6l6GC, but I do know that the cathodyne can be assisted by a pair of gain stages. Moving the input tube into this position would work.

[Bruce / Mission Amps]

The mid 50's 5B4 tweed Super PT is probably rated around 160ma to maybe 180ma and the amp will make about 18-22watts clean.
I've built LOTS and LOTS of "REAL" 25 watt 6L6 amps, with fixed bias using a Delxue Reverb PT, 5AR4 and a black face Pro Reverb OT.
Although the Weber Deluxe PT is "rated" at 150ma, I think it is much closer to 120ma based on my experiences beta testing it for Weber and comparing it to my 6V6 PT and reissue Deluxe Reverb PTs.
The footprint of the Deluxe PT is smaller then the punch out in the Super chassis so you'll have to come up with an adapter ring.
Since you are doing your own circuit board for this project, and you want to build a great amp, so, build a 5F6A Bassman using 6V6s and the tranformers you have but don't bother with a mid range control.
Instead use a 10k or 12K resistor under the bass pot.
I have done this amp a few times and it is great fun.
Now you'll get the extra gain of the long tail pair phase inverter plus the two channels can be tweaked for tone.
Use different cathode bypass caps and coupling caps on the preamp triodes for bright vs normal ... OH... use a 12AY7 for the first preamp tube so the rest if the preamp doesn't drive the socks right off the 6V6s.
You will not need anywhere near as much drive as you would with 5881/6L6s.

[Mark Buckingham]

Since you are doing your own circuit board for this project, and you want to build a great amp, so, build a 5F6A Bassman using 6V6s and the tranformers you have but don't bother with a mid range control.
Instead use a 10k or 12K resistor under the bass pot.
I have done this amp a few times and it is great fun.
Now you'll get the extra gain of the long tail pair phase inverter plus the two channels can be tweaked for tone.

Thanks Bruce... Just wondering... Would the bassman tone circuit sound much different from the tweed super? I'm thinking of basically using the super circuit up through the tone controls, then switching to the bassman pi & power section... Would that work any differently?

Thanks again.

[Bruce / Mission Amps]

The Bassman tone circuit sounds very very good for a slightly more modern guitar tone. It is probably more versatile then the older tweed two tone control setup.
The stock 5F4 style is more tweedy sounding with a certain upper midrange hump that you can add to with the treble pot.
They both sound good but I think the Bassman has a bit more clear treble response and sounds more Marshally when really overdriven.