Ceriatone Forum

Ceriatone => Overtone => Topic started by: CeeEm on August 18, 2011, 12:48:15 AM



Title: EL 34's vs 6L6's
Post by: CeeEm on August 18, 2011, 12:48:15 AM
Any thoughts on EL 34's as opposed to 6L6's in a 100watt BM HRM? My BM has 6L6's with transformers that can handle the conversion to EL 34's.


Title: Re: EL 34's vs 6L6's
Post by: bluesfendermanblues on August 18, 2011, 08:17:15 AM
I Use EL34's in a #183 clone and a HRM.

IMO EL34 are not very different sounding than 6L6 - in a Dumble amp (where you don't tend to drive the power tubes into distortion. Its another story in plexi Marshalls if you drive the power tubes into distortion)

El34s have a firmer bottom end and can therefore seem to have a little less middle.
However, we are talking very minor sound details.

I dont hear a lot of difference between a #183 w. EL34's and a #102 w. 6L6's once the music plays - at rehearsal or gigs.

When I play alone at home, I can hear all kind of tiny minor difference between this or that capacitor/resistor/tube/speaker/cable/pickup/string/pick  ;D


Title: Re: EL 34's vs 6L6's
Post by: CeeEm on August 18, 2011, 09:03:58 PM
Thanks blues-

I've heard that about the D-style - that the power tubes don't make that much of a difference. A tighter bottom could be better though ;)
I always thought that EL 34's had more a pronounced mid-range than the 6L6's but I guess it's not that obvious in this type of circuit.


Title: Re: EL 34's vs 6L6's
Post by: Tone Control on August 18, 2011, 10:27:27 PM
Any thoughts on EL 34's as opposed to 6L6's in a 100watt BM HRM? My BM has 6L6's with transformers that can handle the conversion to EL 34's.

for info generally for others, Nik told me that the stock BM50 takes EL34s, just readjust bias to 35mV once they're in.
I think I'll try some soon. I like the El34 clean in my matchless and my Carr


Title: Re: EL 34's vs 6L6's
Post by: 212Mavguy on August 21, 2011, 12:18:23 PM
I have a 50w HRM, it has a pair of old stock Siemens el34's in it, bias is currently at 33-36mv, not a perfect match between those tubes.  It goes into a 1/15 using an old Jensen Vibranto...it sounds absolutely wonderful clean or dirty.  I would say that the mids are more, bass is less than a pair of 6l6's.  Gorgeous upper mid harmonic bloom with the el34's.  With the bias set hotter, around 39-42 it goes into harmonic feedback/bloom sustain at slightly lower volumes, along with slightly less top end and more bottom/lower mids.  I stuck some pearl tube coolers on them as well as the preamp tubes, they really do work...both for cooling and slight microphonics reduction.


Title: Re: EL 34's vs 6L6's
Post by: CeeEm on August 21, 2011, 06:31:37 PM
Thanks 212 mavguy, nice description, kind of what I'd like. I think I'll try the EL 34's when I get the cash for 4 matched ones ( or rather 2 matched pairs ). I'll use your settings when I take it to my tech although he's not of the hooter bias school of thought.  He's a great builder ( built me a 16watt "tweed deluxe" that sounds wonderful ) but somewhat opinionated I'll have to convince him to try it hotter. Besides the NOS ones, anyone have favorites of currant production EL 34's?


Title: Re: EL 34's vs 6L6's
Post by: 212Mavguy on August 22, 2011, 02:55:26 AM
I have both winged C el34's and JJ e34l's.  I find that the winged C's have more treble response overall than the JJ's, my ears prefer the JJ's in a D-style amp, but I'm sure if you biased them a bit hotter that the Winged C's would sound fuller in the mids and bottom.  I know that their 6l6's benefit from a slightly hot bias as well. 

As far as increased heat from hotter bias is concerned, I'm really sold on the tube coolers thang for power tubes.  I have both IERC and Pearl types.  Apparently in the 50's cold war era some pretty thorough research confirmed that when regular tube glass gets very hot, that it becomes more porous than when cold, lets air molecules pass through, compromising both quality of vacuum and overall tube life...significantly.