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EL34 recommendations

mikecj

Member
2007-12-25 12:37 am
Just purchased my first tube stereo a Jolida 302. I'm on a budjet and am satisfied so faqr with the improvement over the "crap" ss system I was running.

I have been using tube guitar amps for decades and have been building them for a few years no.

What I am looking for is recommendation or opinion regarding the el34 in the Jolida and which brands are preferred for the HIFI application. [came with chinese glass sounds okay]

I have upgraded the coupling caps, and have a pair of NOS GE long plate 12ax7 and a pair of nos GE 12at7wb that I will replace the stock tube with.

I would like some feedback re the el34 though. JJ, Groove, EH,?????

Thanks
Mike
 

jduffy

Member
2006-10-18 2:40 pm
I agree, you gotta get some tubes and live with them for a bit to see how they work out. In time you find which ones give you the warm and fuzzy feeling.

From my experience with the 34 in a guitar amp, they can be so different, even from the same manufacturer!

Snag a few and do some listening tests. I'm sure some people will post here with their choice picks.
 
Hi Mike,

I'm also interested in new EL34's for my 302B, still using the original Shuguangs, but wired in triode. I was going to try JJ KT77's, but they seem to have gotten a pretty bad reputation, so they're off my list.
I tried a quad of Ruby EL34's briefly, they sounded like they would be better in a guitar amp, nice tone but not very hifi.

Rumor has it New Sensor is coming out with a KT77 reissue (waiting to see what they are like).

Stretching the budget a bit, there is also NOS RFT/Siemens EL34, which are supposed to be excellent but not cheap.

What caps did you use for coupling? I have some Russian .22uf K40 pio's, but they aren't in yet. The leads appear to be too short to reach without modification.

Jeff
 
SED makes a nice EL34. If money is no object then a set of Mullard xf2's.

Also be aware that Ruby = Sino = Shuguang as far as I'm aware.

I've also found that for preamp tubes anything blackplate is the way to go. RCA's if you can get 'em. Sylvania 6679 blackplates make a great 12at7 alternate and are cheap.
 

mikecj

Member
2007-12-25 12:37 am
Thanks for the replies and links guys....

Jeff I used "Kimber" to replace the interstage couplers mainly because they are what I had on hand.

Any one had experience with the Groove Tube " reissued "Mullard "Style"" EL34s ordered in the 6 to 8 range of their "breakup / distortion" index ???

Thanks again all

Mike
 
I would question the quality of most of JJ's tubes. I have JJ EL34's, EH EL34's, SED EL34's, new production Tung Sol 6L6GC-STR, Chinese 6L6's, etc. I believe the Shuguang EL34B is a nice tube for little money. The SED is a nice step up from them. Next on my list would be a quad of the TAD mesh plate EL34's.

As far as the driver goes, I would adjust the operating point of the 12AX7 to draw more current and replace it with a 12AV7. 12AT7's are a dime a dozed on eBay. Sylvania grey plates ought to be great in that app.
 
I'm going to be rude and hijack this a little...

Does anyone have any recommendations for new production EL34's based solely on electrical stability and reliability? I need 5 for a bench power supply.

Feel free to tell me off for hijacking and I'll go and start my own thread, but it seemed to make sense to butt in here.