jj tubes and mesa power amps

[frehley]

I've been on the Eurotubes website and saw some info in which Eurotubes claim
that the bias on most Mesa stuff is set really cold and can benefit from a bias mod or the use of hotter JJ tubes to bring up the bias to where it supposedly
belongs. Well, I decided to try their JJ E34L's and three ECC83s P.I. and got popping and crackling noise with them after a few minutes. I found that I prefer
the tone of 6L6's over EL34's as I played but I took out the JJ's and put the Groove Tubes 6L6S's and the Mesa P.I. tubes back in and the noise went away.

The main reason I tried the JJ tubes was because I wanted to try a tube that
would give me the "proper" bias of the amp but I got this crap instead.

I see some of you like JJ tubes but is there any merit to their claim that Mesa sets the bias on their amps too cold? If it turns out to be total B.S. then I'll just
stick with the Groove Tubes 6L6S's which I like very much but if not, then I might try the JJ's one more time. Any info would help.

Thanks!

 

[krankguitarist]

Re: jj tubes and mesa power amps

I've been on the Eurotubes website and saw some info in which Eurotubes claim
that the bias on most Mesa stuff is set really cold and can benefit from a bias mod or the use of hotter JJ tubes to bring up the bias to where it supposedly
belongs. Well, I decided to try their JJ E34L's and three ECC83s P.I. and got popping and crackling noise with them after a few minutes. I found that I prefer
the tone of 6L6's over EL34's as I played but I took out the JJ's and put the Groove Tubes 6L6S's and the Mesa P.I. tubes back in and the noise went away.

The main reason I tried the JJ tubes was because I wanted to try a tube that
would give me the "proper" bias of the amp but I got this crap instead.

I see some of you like JJ tubes but is there any merit to their claim that Mesa sets the bias on their amps too cold? If it turns out to be total B.S. then I'll just
stick with the Groove Tubes 6L6S's which I like very much but if not, then I might try the JJ's one more time. Any info would help.

Thanks!

I ain't exactly an expert, but this is what I know (or, rather, what I think I know):

Mesa/boogie tends to use a "fixed" bias on their amps, and AFAIK, tends to set the bias relatively cold in their rectifier series. I'm not sure about the other models, and I'm certainly not sure about the power amps.

What power amp are you running? Is it switchable between EL34-type tubes and 6l6-type tubes? If not, swappin those two types of tubes out is a defininte no-no. If yes, well, onto the next point...

You should not simply assume that if you put a "hotter" set of tubes in there that your amp will be biased correctly. You really wont have any idea whats going on until you measure the bias itself. If you're new to biasing, I'd say take the amp to a tech to have it biased. If you have some basic knowledge and skill with electronics however, and dont mind shelling out for a bias probe, some of those articles on the eurotubes website can be remarkably helpful. Thats where I learned how to bias my amps.

As for JJ/teslas, I'm a fan. I've got em in every amp I own, and I highly reccomend their 6l6GC tube.

 

[Johnny Q]

Re: jj tubes and mesa power amps

I've been on the Eurotubes website and saw some info in which Eurotubes claim
that the bias on most Mesa stuff is set really cold and can benefit from a bias mod or the use of hotter JJ tubes to bring up the bias to where it supposedly
belongs. Well, I decided to try their JJ E34L's and three ECC83s P.I. and got popping and crackling noise with them after a few minutes. I found that I prefer
the tone of 6L6's over EL34's as I played but I took out the JJ's and put the Groove Tubes 6L6S's and the Mesa P.I. tubes back in and the noise went away.

The main reason I tried the JJ tubes was because I wanted to try a tube that
would give me the "proper" bias of the amp but I got this crap instead.

I see some of you like JJ tubes but is there any merit to their claim that Mesa sets the bias on their amps too cold? If it turns out to be total B.S. then I'll just
stick with the Groove Tubes 6L6S's which I like very much but if not, then I might try the JJ's one more time. Any info would help.

Thanks!

Most folks like the JJ's and many folks swear by them in thier Mesa's, but I am one that strongly disagrees with that. I retubed my Rectifier completely with ecc83's and 6l6's and it sounded like I placed a blanket over the amp. I also had some "shooshing" and sputtering sounds - I will never use them again. The EH's work best for me in that amp, with the Ruby Select Grey plate Chinese pre's a close second.

JQ

 

[ES350]

Re: jj tubes and mesa power amps

The JJ power tubes have been having some serious problems regarding the tooling for pin size---another problem is the rate of microphonics in their small signal stuff. I won't use them if I have to throw away 1 out of 3.

 

[Gearjoneser]

Re: jj tubes and mesa power amps

Tell Bob what happened, and ask him if you can send them back for the same number of JJ 6L6's.

E-34L's have a way hotter bias than 6L6's. They're 10% higher output than EL-34's. I'm actually surprised that he'd suggest something that biases at 39mA in place of something that biases at 32mA, but I've heard a few erroneous things he's advised in the past. He's not the guru people make him out to be. He's simply a JJ distributor.

 

[H8Red442]

Re: jj tubes and mesa power amps

I bought my Dual Recto from ebay with JJs in it and when I got it I wasn't thrilled. I put in the mesa tubes as the seller had included them and it was night and day. Not a fan of the JJ tubes.

FWIW, Rectos have switchable bias.

 

[muttonchopsrule]

Re: jj tubes and mesa power amps

frehley, what power amp are you using the JJ's in???

i've tried out groove tubes, EH, tung-sol, JJ and the stock mesa tubes in my dual rec, and i prefer the EH over all of them, at least in the V1 slot. i think i still have some JJ's in other slots in the preamp, but it's been a while since i've been home from school so my memory is a little sketchy.

never have tried JJ power tubes, but i've found that i'm perfectly happy with the tone of GT E34L's.

 

[frehley]

Re: jj tubes and mesa power amps

Hey Guys,
Thanks for all the great insight. This is what I wanted to get, your feedback.
Hey Krankguitarist and Muttonchopsrule, I have a Mesa 2:100 dual rectifier power amp. I decided to try the JJ E34L tubes because I thought I would like their midrange better but I've been spoiled by the massive lows of the 6L6. I realised what I wanted from the power tubes was a thick tone with huge dynamics and less compression. Anyway I spoke with Bob today and he sounded a bit irritated which I can understand I suppose and he explained to me that the problem might be that the extra pin hole that's not used by the 6L6 might be dirty and should cleaned. He didn't seem to think that maybe the problem might be a faulty tube or the use of tubes that are too hot. He also said that unless the tubes have absolutely no scratches on the base, he won't even replace them. This bummed me out because I explained I wanted to exchange them for 6L6's instead but some tubes have some scratches so I guess I'm stuck with these.
Muttonchopsrule, I also tried the GT E34LS tubes and thought they were really good but I prefered the GT 6L6S tubes and that's what I have in there now. I'll keep you all posted on this. Thanks again, I appreciate all your opinions!!!

 

[muttonchopsrule]

Re: jj tubes and mesa power amps

Hey Guys,
Thanks for all the great insight. This is what I wanted to get, your feedback.
Hey Krankguitarist and Muttonchopsrule, I have a Mesa 2:100 dual rectifier power amp. I decided to try the JJ E34L tubes because I thought I would like their midrange better but I've been spoiled by the massive lows of the 6L6. I realised what I wanted from the power tubes was a thick tone with huge dynamics and less compression. Anyway I spoke with Bob today and he sounded a bit irritated which I can understand I suppose and he explained to me that the problem might be that the extra pin hole that's not used by the 6L6 might be dirty and should cleaned. He didn't seem to think that maybe the problem might be a faulty tube or the use of tubes that are too hot. He also said that unless the tubes have absolutely no scratches on the base, he won't even replace them. This bummed me out because I explained I wanted to exchange them for 6L6's instead but some tubes have some scratches so I guess I'm stuck with these.
Muttonchopsrule, I also tried the GT E34LS tubes and thought they were really good but I prefered the GT 6L6S tubes and that's what I have in there now. I'll keep you all posted on this. Thanks again, I appreciate all your opinions!!!

that's kind of s****y, i think that's the first time i've heard of someone having such a negative experience with bob.

that's how it works with tubes though, you gotta try out whatever you can get your hands on and see what you like most. so now you just have one more thing crossed off the list .

 

[Binnerscot]

Re: jj tubes and mesa power amps

I have always liked JJs for power tubes (both E34Ls and 6L6s). I like EH on most occasions for 12AX7s. Sounds like a faulty tube, not the end of the world.

 

[Binnerscot]

Re: jj tubes and mesa power amps

frehley, what power amp are you using the JJ's in???

i've tried out groove tubes, EH, tung-sol, JJ and the stock mesa tubes in my dual rec, and i prefer the EH over all of them, at least in the V1 slot. i think i still have some JJ's in other slots in the preamp, but it's been a while since i've been home from school so my memory is a little sketchy.

never have tried JJ power tubes, but i've found that i'm perfectly happy with the tone of GT E34L's.

Dual Recs come with "Russian 2s" which are Mesa rebranded EH....