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Tung-Sol 12AX7

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well im not positive as to what the tungsol 12ax7 is , I did by one new set of 12ax7s from my local guitar shop, the only ones they had in stock wear actually labeled as mesa bogie tubs, I have no idea who makes them because there was no lable on them but, that said, I used in my black heart little giant to see if it was better than the stock china one, it was smooth and had plenty of cream'n overdrive I was pleased, until i was givin a box full of old tubes to play with...thats a whole other story now

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Just like any other tube, particularly 12ax7s, and especially new production 12ax7s, you've got to find good ones before you can really make any assessment. By "good," I mean they have good gain, excellent conductance, minimal, if any leakage, and low microphonics.


Once you get past those tests, you have a good tube to work with. Then, and only then, is it viable to start comparing for tone and performance differences. Brand name means virtually nothing otherwise, nor does NOS vs. new production. ANY tube can either pass or fail these critical first tests, and, the fact is, regardless of what you may have spent for it or what the fancy label says, if a given tube is low in gain, has poor conductance, is leaky, and/or highly prone to microphonics, it's going to perform much less admirably than a tube that passes those tests with flying colors.


That said, if/when you DO find a Tung-Sol re-issue that passes, they're fairly highly regarded amongst the rather dismal current crop of new production 12ax7s. The trick is in finding one/some that pass with high marks across the board. One of the characteristics of new production 12ax7s seems to be that they're rather low in gain. Another is that they tend to be rather prone to microphonics.


All of this simply means that you HAVE to buy tubes from a reputable source that is thoroughly testing them before sending them out the door. If you buy via mystery Ebay source or simply over the counter at a music store, your odds of getting a truly good tube are minimal at best. Sad fact of life these days.


FWIW, a friend of mine who writes reviews for a leading guitar magazine is currently testing transistor-based "12ax7" replacements that MIGHT just be "the ticket." Time will tell.

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Like I said, if you can find good ones, the Tung-Sols seem to perform well and get good reviews. I've been using one in V1 of one of my amps, and I've got no complaints.


Generally, I've been mostly using JJs for the past few years, because they make a great el84, a very good el34(L), a great 6v6, decent 6l6, and decent 12ax7s, although the gain on them is real sketchy so they have to be bought from a source that grades them.


I recently ordered a TAD 12ax7 (7025s, I believe) and a pair of genolex el84s for another amp, just to try them. My tech buddy is disgusted at my choice, but I've read decent reviews on them both, so I figured I'd try them for myself, just to see what they're like.


The thing is, all tubes are terribly inconsistent these days, including NOS. I've had NOS that've been horribly microphonic. With regard to new production, you can find utterly useless crap and fully acceptable examples from within the same batch. The only thing consistent seems to be the inconsistency.


So, I try to take the general forum comments with a grain of salt. Who knows whether that tube that Joe Schmoe on the forum is either belly-aching about or ranting and raving about was tested before it was sold, and where it measured on proper test equipment? If he bought a really strong 12ax7 that has brand xyz stamped on it, how can he make a legitimate comparison to brand abc, without knowing that both tested identically on test equipment?


In other words, let's say that you have an EI and a JJ 12ax7. You throw them both on your test equipment and find that the EI measures "130" in gain, while the JJ measures an anemic "80." Given that we're using the same gear, these numbers have some meaning. Let's assume that conductance is identical and neither tube has microphonics issues. Do you think that MAYBE, just MAYBE the fact that one tube has about 40% more gain would affect the way that it performs, especially in V1?


So, given this, isn't it remotely possible that, if the numbers were reversed, and it was the JJ with 130 gain and the EI with 80, the same person who swore by that "magical" EI would be instead swearing about the "magical" JJ?


The fact is, there's an awful lot beyond brand name that goes into whether a particular tube performs satisfactorily or audibly better than another similar tube. Unless we know that all possible variables were equalized, nobody can say for certain that a specific brand produces a better or worse tube.


This can also be said of NOS, although, in terms of tone, it's hard to argue that, all other things being equal, NOS DOES have better, more musical characteristics. The thing that bugs me about NOS discussions is when you see someone make the absurd statement that "NOS tubes last YEARS longer than new production, because I just pulled some from a 40 y/o amp that tested almost new!"


Big f'ing deal. Park a new blues jr. for 40 years, pull the new prod. tubes, and I'll almost guarantee you you'll find them to test almost new, also. So what? We've no way of knowing how many hours that 40 y/o amp was in use, nor how hard it was pushed during its work hours, so attempt to use pulling good old production tubes from a 40 y/o amp is utterly meaningless.


Similarly, you'll often see raving reviews about brand xyz tube that "made my amp come alive like never before!!!," from guys who will openly admit that they've never replaced output tubes before. Well, duh. If you're gigging heavily, you're going to chew through them every 6-12 months. Sorry, but that's reality. So, if you've gone 5-6 years with the same tubes, of COURSE whatever you replace them with are going to sound AMAZING. Your ears have been putting up with dull and mushy for years, genius!

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lol, I hear ya. I wish I had testing equipment. It's on my list of priorities, just way down on the list. What I recently did to compare power tubes was to first plug in and listen, for the initial reaction. After that I put a mic on my amp and played loudly distorted, then quietly clean. The quiet clean playing did uncover a more musical and richer harmonics from one tube. Some day I'll have testing equipment, or at least know somebody who does.


I have a JJ 12ax7 that I'm going to try replacing with the Tung-Sol. Buying tubes is a crap shoot to me. Good thing tubes are relatively cheap. Backups are nice to have as well, even if they don't have that perfect tone.


BTW, I always buy from reputable sources as far as I know. The last JAN/Phillips 6v6 I bought had some measurement marked on the top, so I'm guessing it was tested. That's the one that sounded more musical to me over a new Tung-Sol 6v6 I had in there using the recording test.

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When I ordered replacements for my BC30 I ordered tungsol 12ax7 and a pair of jan-philips 5751 to experiment... I now have both 5751's in V1 and V2 because they make the amp sound so much smoother. The tungsols were an improvement over the stock tubes, but the 5751's sound so good.

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Guest icantbuyafender
The Tungsol 12ax7 came yesterday. It's more musical to my ear. I tried a JAN 5751 in there too. That's definitely a softer tube.



The replacements Pyotr Belov sent me and the stock tubes in my Lil' Giant 5 blackheart amp were all GrooveTubes.


The 12ax7's, that is. The EL-84 was a cheapy.


hmm, wierd?


I've heard great things about tung-sol tubes.

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