6V6 with A3801 ?

[rdjones]

Greetings all.

<background>
New member here, but long time reader and contributor to A.G.A. (on topic ONLY) as well as rec.audio.pro. old timer around tubes and transformers.
Engineering degree from Kent, former MI tech, etc.
= = =

I just received a Stancor A3801 OT and was planning on using 6V6s
for TW Express style amp. The choice of 6V6 is not set in stone, but I'd prefer to avoid EL34s for various trivial reasons. Knowing that some TWs use 6V6s is appealing.

The first impression is that the '3801 is way too big for the 6V6s.
It's way heavier than any other 6V6 output I have, or can recall.
It's significantly larger than the OT on my 50 watt MusicMan.
I kinda feel like that heavy iron will go to waste with the lower power level associated with 6V6s.

I don't really need another 50 watt or higher amp.
So I'm just looking for discussion, suggestions, opinions and observations about using 6V6s in an Express type circuit.

rd

[Cliff Schecht]

3300 Ohms per side is a bit on the low side as far as the 6V6's are concerned. 6V6's really like a 4-5k load (per tube) for optimum performance but can sound just as good in guitar amps with a lower impedance load, it's just a matter of adjusting the bias accordingly so that your quiescent point is about the same. The 3801 is definitely overrated for 6V6 operation, but then again a big point of the Express design is to overrate everything so that nothing in the system gets too stressed.

[2tone]

My old transformer Express is running 6v6's, they sound grand. It's my favorite rock amp......

[hairyandy]

It's better to have too much iron (which the 3801 really isn't) than not enough! The 6V6s will sound great, but once you bias it up with a good pair of EL34s you will never even CONSIDER going back.

Andy

[2tone]

Actually I prefer the 6v6's in this amp. Ken thought it was killer w/6v6's also. The 34's are grand sounding, but for some reason this Express likes 6v6's, and they respond beautifully, all the dynamics and punch, plus a little richer sounding..This was the first Express ever made..

[funkmeblue]

....so how does she sound as a bass amp?

[ampmike]

Hi,Im using 6v6 with the pacifics and Im set on those tubes,I got some philips nos for 50 bucks and Im very happy!!!!! Mikey Good Luck!

[2tone]

Ha you knew about the Bass toggle?! It does a great job at bass too, especially w/ the right cab. Also cool on guitar....for fuller low mid sounds

[Cliff Schecht]

I have a few good sets of NOS RCA/Sylvania 6V6's from the WW2 era that I think sound better than any EL34's that I've used in my Express. My first few posts about the amp after completion were how much the 6V6's in this sounded better than 34's in both of my Express'. The only reason the 6V6's don't stay is the reduction in headroom kills me when I'm playing onstage and need a decently loud clean. Did you know you can play some nice twang on an Express too?

[Blinkie]

Lori also sounds good with 6v6's. Depending on the mood....34's or 6v6's. Either way is a winner!

[redshark]

I've tried the "holy grail" RCA 6V6's in my express with pacific transformers but in that amp I think the old Tungsol 6V6 is the winner. My pair are labeled delco but made by tungsol and it offers a rounder sound for the express IMO.
I would like to try a pair of old tungsol 5881's but I think I would need to change a resistor in the bias circuit to do that.
Has anyone tried those tubes?

[alanp]

I'd be interested in hearing whether Expresses like KT77's.

[Richie]

may have to do some digging, but in the old RCA books they usually suggest the transformer to use with what tube, and for the purpose. Many times they suggest Stancor transformers. But many of the old transformers were made by Chicago. So even if its a Merit or whatever, its the same thing.
You can look those up in the cross books too.

[breakfastbuddy]

the 6,6k OT is smaler than it is , because off the weaker steel in it . i think that the original el 34 setup is going on for a saturation core sound .
a 6v6 aproash is making the amp feel stiffer i think .
try out a smal iron i think thats closer to what the target .
what about using a ecc 88 cascode boosted front in a trainwreak express instead of the 1/2 side of the ecc 83 , can i just download some gain and be there ?

[breakfastbuddy]

the 6,6k OT is smaler than it is , because off the weaker steel in it . i think that the original el 34 setup is going on for a saturation core sound .
a 6v6 aproash is making the amp feel stiffer i think .
try out a smal iron i think thats closer to what the target .
what about using a ecc 88 cascode boosted front in a trainwreak express instead of the 1/2 side of the ecc 83 , can i just download some gain and be there ?