100K plates driving 2 X El-34

[Tonegeek]

Anybody done this and if so did you use the Fender style PI or the Marshall style? How did it sound? I have a commission to build a 50w D type amp and I always wanted to try something like #124 but into El-34's instead of 6L6's. I have a 100w low plate #124 that I really like and I connected the preamp to my 50w BM output and got some pretty good sound out of it. If I can't get the happy feeling going for this configuration, I will instead build #183 with a few tweaks. The customer has given me a lot of flexibility to kind of do my own thing so it should be lots of fun and I want to take the opportunity to do something I have not done before. We have settled at least on using the non-HRM platform w/EL-34 but the rest is open to discussion.

[talbany]

Anybody done this and if so did you use the Fender style PI or the Marshall style? How did it sound? I have a commission to build a 50w D type amp and I always wanted to try something like #124 but into El-34's instead of 6L6's. I have a 100w low plate #124 that I really like and I connected the preamp to my 50w BM output and got some pretty good sound out of it. If I can't get the happy feeling going for this configuration, I will instead build #183 with a few tweaks. The customer has given me a lot of flexibility to kind of do my own thing so it should be lots of fun and I want to take the opportunity to do something I have not done before. We have settled at least on using the non-HRM platform w/EL-34 but the rest is open to discussion.

Here is basically a 124 (prototype Bassman conversion amp) originally with a quad of Mullard X4's (I believe)
The amp went to Coy Bowles who plays with Zac Brown who AFAIK has had it on the road for several years and loves it..

Tony

[ER]

I used the power supply, PI, and power section like #183, Mated to a low plate early style front end and OD (but with an added OD tonestack). The only changes I made in the power section were 100uF caps in the 1st stage of power supply, 1k instead of 1k5 on pin 4 of the power tubes (JJ-6ca7) and a 12at7 PI tube. Running the 6ca7's around 70% (477v plates ~@ 35.5mA).

After owning a dozen or so amps over the years I like this one best, and not just cause I built it. Power amp wise it is more open and full sounding than I remember my 100W marshall (4xel34), Hiwatt lead 100 (4xel34), dean markley CD120 (4x6l6), and even my strategy 400 (6x6l6 per side).

I was afraid it might sound too "british", but I heard from others that the 6ca7 was a little more "american" sounding, kind of a happy medium between EL34 and 6L6GC. I'm not sure if it's the circuit, the tubes, or what but it does sound like the best of both worlds to me.

It's a loud bugger especially with EV's, 2x would probably be plenty especially in this era of church mouse amps. I just suffer from PTSD from a drummer I used to play with...

[trane34]

Since you are able to tweak till it sounds good, why not start with the stock #124 and go from there? I played some Ruby EL34's in my stock build and they sounded great. In my experience the EL34's held up better with more harmonics on single note runs. Though a pair of SED 6L6's are hard to beat. Sounds like a cool customer to work with.

[Tonegeek]

After thinking it over and taking suggestions, I am indeed going to go with low plates, the Fender PI and 2 EL-34s. Gil Ayan steered me to 100k plates a while back and so far I like them for the most part, but I have only done this with non-hrm, 6L6 amps until now. If I can't get it right, then I will replace with high plates and steer toward #183. BTW I will be using Marshall Iron - an MC JCM 800 PT and a Mercury OT (working with them now on what I want). If I have time, I will post build notes, pix but I am over booked right now and feel guilty even for writing this post. Actually i will still take pix so even if it is not along the way, I will post them at some point. cheers