Best sounding current production EL34, what are you guys using ?

[Nigel]

Thanks....I have a YBA-1 bassmaster, which doesn't have an adjustable bias pot, but Tesla EL-34s do fine when tested (with a bias probe device), drawing 32 mA and sounding fine. So I leave that amp completely stock.
The YBA-1A Mk II bassmaster is the one I'm more concerned with, as it has higher plate and screen voltages, to put out ~ 80 watts from 2 power tubes (originally American 6CA7s back in the 70s). Fortunately, it has a bias 'wiper', and with the Teslas I can adjust for a current draw of 34 mA & it sounds great. I think the wiper is turned all the way to one side for that value, ie, I could adjust it for higher current if needed, but not lower).
I'm just curious if you had to install a bias part in a YBA-1 amp to take the KT77s. Or if anyone has a YBA-1A Mk II, if the adjustable bias wiper didn't allow for a workable current draw.
(Btw, I subscribe to Aiken's view ('the last word on bias') on bias - how it's mostly to avoid obvious over-bias (where it sounds lousy), and obvious under-bias (where the plates are getting that subtle red glow). In between is a wide range where it all sounds good, so I tend to go with the lowest current draw that sounds good - usually high 20s to lower 30s). thanks!

I find the JJ KT77 sounds best when slightly red-plating. I keep a strong set in for jamming and a weaker set that begins to glow for recording. Tubes can sound best when they are about to die!

 

[napalmdeath]

I tried a pair of EH 6CA7's in my Laney, and they really pack a wallop, and sound damn good. I had Tungsol EL34B's in it prior, and they are excellent as well. But, the EH's are staying in there.. They both dethroned my go-to KT77's.

 

[GlideOn]

Thanks....I have a YBA-1 bassmaster, which doesn't have an adjustable bias pot, but Tesla EL-34s do fine when tested (with a bias probe device), drawing 32 mA and sounding fine. So I leave that amp completely stock.
The YBA-1A Mk II bassmaster is the one I'm more concerned with, as it has higher plate and screen voltages, to put out ~ 80 watts from 2 power tubes (originally American 6CA7s back in the 70s). Fortunately, it has a bias 'wiper', and with the Teslas I can adjust for a current draw of 34 mA & it sounds great. I think the wiper is turned all the way to one side for that value, ie, I could adjust it for higher current if needed, but not lower).
I'm just curious if you had to install a bias part in a YBA-1 amp to take the KT77s. Or if anyone has a YBA-1A Mk II, if the adjustable bias wiper didn't allow for a workable current draw.
(Btw, I subscribe to Aiken's view ('the last word on bias') on bias - how it's mostly to avoid obvious over-bias (where it sounds lousy), and obvious under-bias (where the plates are getting that subtle red glow). In between is a wide range where it all sounds good, so I tend to go with the lowest current draw that sounds good - usually high 20s to lower 30s). thanks!

Yes, modern EL34s that can tolerate 500+ v on plates are a crapshoot, but hey even more reason to use KT77 which were designed with high plate voltage in mind, they won't even break a sweat

 

[robk916]

JJs seem to be the most consistent from tube to tube. When you get a good set of mullards, those can be pretty magical as well

 

[tlp1234]

JJs seem to be the most consistent from tube to tube. When you get a good set of mullards, those can be pretty magical as well

JJ's for the longest were some of my favorites. Not because they sounded good/bad to my ears, but because they lasted a long time. Extremely seldom ever got any that failed prematurely.

But.....during 2020-21 I got 7 in that period that failed. Some after only a few hours, others a couple of months. And I always bias them on the cold side. Didn't give much thought to the first couple of failures as there always seem to be some crappy ones that slip through QC.

I finally gave up on the JJ's. Same with TAD's.

I had a spare set of Mesa branded EL34's and put them in my SB50 after two failed pairs of JJ's. It's been a year now of consistent thrashing, and they (Mesa branded EL34's) are still sounding and holding up remarkably well.

I've changed over to Mesa branded EL34's, 6L6's, 5881'a. I really believe Mesa tests them extremely well before they go out for sale. During the supposed "vacuum tube drought", I tried a number other vendors with bad results. Of course it could have been an extremely odd string of bad luck, but I doubt it.

Although I'm certain Mesa has their share of tube failures even after their rigorous testing, I've yet to have any Mesa power tube fail on me prematurely.

Unfortunately, I cannot get them (Mesa) to sell me any tubes at all as of late. I just got a 30yr old MKIV Rev A (my second one this year) fully restored by Mesa. I was astonished that even for that service event they would not sell me any tubes. Fortunately, I still have a stash of Mesa Branded STR 415's Sylvania 6L6's that I bought back in the very late 80's when you could still buy them in quantity. I bought a bunch and people thought I was crazy (aka moron) at the time. I'm glad now I did.

I heard lots of talk of Western Electric spooling up to produce popular application audio tubes during the brief "OMG the sky is falling no more tubes from Eastern Europe/Russia, and OMG the China Shuguang factory has burned down WTF are we going to do?" era. I finally quit visiting the stupid ass TGP because of all the cringing and knashing of teeth and a new thread or two everyday about how the sky is falling no more tubes. (jeeez TGP is a bunch of fucking idiots!!!!).