EL34 Lovers?


What are your favourite amps using EL34 tubes? And why?
pubul57

Showing 6 responses by entrope

Pubul-

I would try a tube change from your JJ tubes to a set of Siemens, RFT, Mullard, Sylvania or Telefunken if you can find the deal.

I have a Sonic Frontiers SFS 40 I use in my B system. I swapped out the JJ's in it for a quad of Siemens as well as the driver/input tubes with Valvo's and it transformed the amp.

What was a passably good midrange while suffering in the high and low end has changed to an excellent midrange with very good highs and quite acceptable clean tuneful low end .

If you are happy with the EL-34 sonic signature- a good set of American or German EL-34's tubes may send you over the rainbow.

Ralph
Pubul-

My tubes were not the "L" version but I have had similiar results with other EL-34 based amps over the years. A Dynaco ST-70 & Sound Valves M-40 both responded to non-russian/non-chinese EL-34's with great improvements in dynamics and range.

It may be worth a tryout since you can resell good tubes easily. You have nothing to lose really by comparing and a non-russian EL-34 certainly will not hurt your amp.

Is this not the nature of this hobby to try new things?
You can't unless you find them used. They were actually made from the Dynaco designed circuits after Dynaco's demise.

A company bought the designs ungraded the components to a degree and started producing Sound Valves amps.

You can find them occassionally here or on eB*y. They are easy to mod and if you like the Dynaco sound can be a real find.

Ralph
I don't understand the reluctance to roll some NOS American or German EL-34's in these amps aside from cost.

I think that you will be very surprised and how much difference there is between tubes.
EL-34 tubes I have tried that I think are better than JJ's:

Siemens- Good dynamics, engaging presentation,solid top to bottom

Telefunken- Rich, good dynamic range, detailed-great tube but pricey

Mullard- original not the Russian reissue . Smooth, warm engaging a bit on the soft side for me but not mushy

Sylvania-great American tube, solid performer, dynamic

Other EL34's with good reputations I have not tried:

Philips
Matsushita -made in Japan from Philips tooling
GE
RFT- german

YMMV
Both circuit and tube determine the sound of a particular component as well as internal components. A circuit can indeed be optimized for a particular tube's characteristics. Does it mean no other tube of the same type will work? Probably not. Could it cause problems? Maybe but not likely. Will you change the circuit? not likely. Will you change the tubes to try to improve the sonics of the circuit? YOU BETCHA!

If you change tubes and nothing else resulting in a change in the sonic signature of the component then it has to be the sonic character of the tube causing the change.

Whether that change is positive or negative is determined by your ears alone. The tweaky nature of this hobby means I am going to try all avenues to extract the sound I most desire from a system. Tube rolling is one of the easiest and most easily reversed ways to do that.

For your peace of mind you may want to compare tube specs between JJ EL34L and other EL34's to find if there is a signifcant difference in the tube voltages and outputs. If there is not then you may be missing some music that is available to you with a tube change.

A quick search on the web seems to point out the only difference in specs between a standard JJ EL34 and the JJ E34L (there designation) is the ability of the E34L to handle a larger plate voltage on grid 1. (-13.5V to -16.5V compared to the standard EL34 -10.0V to -13.5V) All other specs are the same.

Significant? Don't know enough about tube grids or the circuit in your Sonum to say yes or no. Perhaps others can.

Ralph