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Sovtek Mullard replica EL34 question

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10/29/1997 9:23 AM

Sovtek Mullard replica EL34 question

Anyone know how these Sovtek Mullard replica EL34s sound/perform? I'm using matched svetlanas(they sound great) in my matchless chieftain clone but considering trying the Mullard replicas.
BTW, I'm using a (Doug) Hoffman 50watt output transformer in this amp and it sounds way smoother and less top-end-edgy when compared to a real matchless chieftain. Some would consider it a "darker" sound, but I like it and don't really find it dark. Sorry for ramblin'.

Frank

10/29/1997 10:12 AM
James	I used the new "Mullards"/Sovtek in a 69 Marshall 100 watter with 530 volts on the plates. The owner has used the amp now for a couple of months and no problems. I asked him to bring it back about a month ago to re-check the bias and it drifted very little(not enough to concern me). So, I think they pass the test, for now. Let's see how they hold up in the long run. James

10/29/1997 9:54 PM

Frank,
I had an order for EL34's for a Musicman a while ago. I know that the MM runs plate voltages that are very high - like right at about 700vdc!!... so I called NS and asked them about the max plate voltages for the various EL34's. Their reply was that they changed to the EL34WXT (so called Mullard copy) in their MIG-60 to avoid problems with short life, and shortING, since the MIG runs at about 680volts on the plates. Also real high!!

I don't know if that helps any, but I've had good luck with the EL34WXT's

Charles

10/30/1997 9:24 AM

Just as a point of interest, the maximum voltage that a particular version of a tube can handle has to do mainly with arc-over and is related to distance between electrodes, lead wires, base pin location and even base material or geometry. Merely taking an existing plate/grid/cathode structure and improving how it gets connected to the outside world is how some later versions of tubes, with the same dynamic performance, are able to withstand more severe circuit conditions.

Doc

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