Elektro-Harmonix Vacuum Tubes

[cableguy]

For kix I picked up a quad of EH 6VGGT's and have been happy with them in the Maggie amps that I own. I love the original Magnavox tubes but at the same time am happy with the new production EH's....I am tempted to try the Russian Military version of the 6V6's. There are a couple of US sellers now and they remain a bargain.....:scratch2:



Bill

 

[clydeselsor]

I recently bought 6 of the EH 12AX7s and they seem to sound good, as good as the old stock Magnavox 12AX7s that I also have. The EH 12AX7 has a fatter glass body than old stock tubes. Some of the tube shields won't fit over them.

 

[Jim McShane]

They fit now too, since they got the height thing figured out.:yes: In this particular tube number, I'd say the EH sounds better than NOS GEs (at least in a Sherwood 5000). I put a quad in Twantiques Sherwood after a resto, and boy did they sound good. Really controlled "crisp" bass response was their strong point, but the mids and highs were quite nice as well IMHO.

What "height thing" are you talking about? I've never seen any change in bottle height.

 

[Jim McShane]

The best newer tubes are made by Ei and are hard to find They can be perfact copies sonicly to the telefunken as they are an exact clone of them but some are very microphonic and not good in critial aplications so these now rare tubes must be hand selected.THe best sounding 12AX7 I have found is the new reissue Tung-Sol very close to the old Telefunken but with 15% more gain than a standerd 12AX7,makeing them perfact for aplication in the low output Rolls Belarri phono preamp.also the Sovetec LPS and Ei brand are good choices for this tube .A nice and very consitant tube is also the RCA NOS JAN new old stock joint army navy they are not as punchey as the Telefunken but the over all tone is very close.I hope this helps you. After hearing the Ei's next to the Electro Harmonic hand selects it is very obvious why the Ei's got snapped up so fast.They are truly golden.

I think you have a "charitable" view of the Ei stuff. Especially in the last few years of production the quality was horrible. A large % of the small signal tubes were VERY microphonic (as you mentioned), the power tubes (especially the KT-90) were very unreliable and many were built with misaligned screens, and so on...

IF you got a good one they definitely could sound good, but finding a good one was darn hard to do.

Also, based on my actual measurements there is no difference between the Tung-Sol reissues and other 12AX7s in mu (gain). Right now the highest gain 12AX7 generally is the LPS Sovtek - again, based on the 100s of measurements. There are sample-to-sample variations, to be sure, but in general that's what I see.

I like a lot of the new production tubes too - don't get me wrong. But not all are stellar examples of the type.

 

[jaymanaa]

What "height thing" are you talking about? I've never seen any change in bottle height.

Help me out here Jim, am I thinking of JJs being too tall? I remember getting ready to modify the heat shield in a Sherwood 5000 II series to accommodate new production 7868s, when a friend gave me a quad of the new (at least he and I thought they were a new issue) 7868 from EH to try. They fit under the heat shield with no mod, which made me very happy.:yes: I can honestly say too, that they (in this amp) were the best 7868 "or" 7591 (for that matter) I have heard to date. Of course a lot of that could be the amp, after all, I did rebuild and mod it. On the EI thing, the only experience I've had with them worth mentioning is with the "old" KT 90s which are pretty dern good.:yes:

 

[Jim McShane]

Help me out here Jim, am I thinking of JJs being too tall? I remember getting ready to modify the heat shield in a Sherwood 5000 II series to accommodate new production 7868s, when a friend gave me a quad of the new (at least he and I thought they were a new issue) 7868 from EH to try. They fit under the heat shield with no mod, which made me very happy.:yes: I can honestly say too, that they (in this amp) were the best 7868 "or" 7591 (for that matter) I have heard to date. Of course a lot of that could be the amp, after all, I did rebuild and mod it. On the EI thing, the only experience I've had with them worth mentioning is with the "old" KT 90s which are pretty dern good.:yes:

I honestly don't know! The only modern 7868 is the EH. Were you thinking of the 7591A EH that is in a larger bottle than the old stock? That's the only thing I can think of, sorry!:scratch2:

 

[jaymanaa]

I honestly don't know! The only modern 7868 is the EH. Were you thinking of the 7591A EH that is in a larger bottle than the old stock? That's the only thing I can think of, sorry!:scratch2:

No, but that one presents a problem in Sherwoods too, as the bottles actually touch.:thumbsdn: I'll do some research and see if I can figure anything out on the tall tubes.:scratch2: Heck, could be I've lost it.:sigh:

 

[goraman]

I think you have a "charitable" view of the Ei stuff. Especially in the last few years of production the quality was horrible. A large % of the small signal tubes were VERY microphonic (as you mentioned), the power tubes (especially the KT-90) were very unreliable and many were built with misaligned screens, and so on...

IF you got a good one they definitely could sound good, but finding a good one was darn hard to do.

Also, based on my actual measurements there is no difference between the Tung-Sol reissues and other 12AX7s in mu (gain). Right now the highest gain 12AX7 generally is the LPS Sovtek - again, based on the 100s of measurements. There are sample-to-sample variations, to be sure, but in general that's what I see.

I like a lot of the new production tubes too - don't get me wrong. But not all are stellar examples of the type.

I understand what your saying about Ei's post war production I just ordered 4 and hope 2 are good enough to use one at a time in my Bellari but I have been supriseingly lucky with these tubes.I have gotten a bad one or two but the tone of a good one is worth the cherry picking.

As for the 15% more gain in the tung -sol it was on a gutar amp web sight and they said the same for the Sovtek LPS and I have both and have heard both and was torn in picking one of the two but soon an Ei will replace them.

 

[YamahaFreak]

For kix I picked up a quad of EH 6VGGT's and have been happy with them in the Maggie amps that I own. I love the original Magnavox tubes but at the same time am happy with the new production EH's....I am tempted to try the Russian Military version of the 6V6's. There are a couple of US sellers now and they remain a bargain.....:scratch2:



Bill

Have any of you guys ever heard the Bendix 5992 in an amp that uses 6V6GTs? I've heard it's like a 6V6 on steroids. I have a few 5992s but nothing to put them in. :scratch2:

Sorry for hijacking the thread, BTW.