JVM Forum

Just curious if anyone has had any luck with these? I've only used SED winged C's in mine and I'm about ready to order a quad and wondering if I should try something different. I would love to drop a quad of NOS tubes, but that is too expensive.

Good luck. No one is ever on this forum anymore it seems. I heard they are pretty 6L6-like so I stayed away from them. I'm assuming you're talking about the reissues. I haven't actually used them this is just based off reviews I read.

The SED =C= EL34s are some of the best EL34s you can buy nowadays. They are tight and have a smooth midrange. Marshall knew what they were doing as far as the poweramp goes.

True, there used to be quite a bit a traffic here. I was just wondering about the EL34's since most topics here are regarding preamp tubes. Power tubes are more expensive to experiment with and would be good to hear what others have tried before dropping a c-note on a quad that may not work well.

Reliability seems to be hit-or-miss with EL34s these days. I've heard anecdotal reports that the winged-C SEDs are one of the more reliable choices. I think Rachel Morgan posted that Randall advised their customers to use 6L6s in their modular amp, or if they must use EL34s to stick with the winged-Cs, again due to reliability. I think they sound great, too.

DH

Most tube suppliers seem to have more faith in the SED =C=. I have retubed my amp twice with SED's and the first quad was good, but the second quad only lasted about 3 months. They started sounding scratchy on the highs. I thought it was a bad preamp tube so I tested all of them and they were good, so I put the old power tubes back on and the scratchiness went away.

I think I just got a lemon which is likely in tube batches. I just got a new quad that I will be putting in and hopefully these will last. If these tubes fry in two months, then it's a problem with the amp.

Yeah the SED EL34s are solid. I didn't really appreciate them until I got JJ E34Ls. The E34Ls were a little punchier but one of the tubes failed so I threw back my SEDs which I "thought" were old but I popped them in and biased correctly and man those things sounded awesome. The bias was probably off when I first got the amp. I didn't know any of that stuff when I first got it. The SEDs weren't as tight as the JJs but they had more body to them. Eventually I ran them into the ground from being used so much but they are a reliable and good sounding tube.

I have 'em in my Plexi clone...they're just as good as =C= or JJs. I have Shuguangs in my JVM....they just seemed to have a bigger and more balanced tone than the stock =C=.

I just tried a quad of Tung Sol EL34B's in my JVM410. Two of my stock tubes went bad so I ordered a quad of Electro Harmonix EL34's. They are a bit smoother than the stock tubes but one went bad after about 20 minutes of hard playing. The Tube Depot replaced the bad one and I haven't had any more problems with them even after a few gigs.

I read some reviews that said that the EL34B's were great so I ordered a quad. They are definitely a fuller sounding tube than an EL34. They seem to increase the low midrange frequencies warming the tone up. The problem for me is that with the fullness you lose the wonderful Marshall presence/bite that I bought the JVM for. First I put all four in my JVM410 and biased them up to 72mA per side. Too fat and mild for me. Then I took two out and put two EH EL34's in and rebiased. Still a bit too mild, not enough chain saw for my taste. I took all of the EL34B's out and put the EH EL34's back in and biased again at 72mA per side. Back to the in-your-face Marshall bite that makes your pulse rise. I increased the Resonance knob two notches and it fattened up the tone similar to the EL34b's without decreasing the beautiful Marshall presence.

I am going to give the EL34B's another chance in a while, but for now the EH EL34's are where it's at for me.

the current production el34's have a screen voltage limit of 450Volts... right were most guitar amps are or even above...
the SED's have a limit of around 500 volts, that's why most fabricators advise them

PLUS ONE ON THAT!!!

Plus one from me aswell. On the EL34 part, cuz I prefer the =C= :D