Rolled some 12ax7's recently...


Hi All,
I went through my supply of 12ax7's recently and found some goodies.
I recently compared Bugle Boys to Telefunkens in the phono stage of my pre-amp. Interesting (to me, at least). I found the Telefunkens to be nice sounding; very clean and clear, very nice detail, over all a very nice sounding tube. The Bugle Boys, however, were magical! WOW! Timbre was so much more apparent. The soundstage depth and width increased; especially the depth. The music seemed to come alive and glow. It was much more captivating.
I found such a dramatic difference between two high quality tubes very interesting.
I have yet to try 10m's, and 70's Mullards that I found. I will report when I do...
By the way, NOS Sylvania's sound nice in the line-level stage. All tubes reported are vintage NOS. I match them with my tube tester. And, I do not change the volume setting between tube brands tested.
Any comments are more than welcomed! I appreciate any information on your experiences with 12ax7's. The price of some of these NOS is incredible; I am glad to have these nice examples in my collection!
Cheers.
bicycle_man
After looking at record lists, and some thought, I think I can reconcile the seemingly absurd pricing of some NOS tubes. Analogizing it to record prices, some records are exquisite, rare, and no longer produced, and thus priced accordingly.

That doesn't mean I won't shiver when I see the prices. I just understand that they are not made anymore, and that they are masterpieces of their genre, hence command a pretty penny. Of course, I will avoid them because of higher priorities for my money.

Of course, deep down I still will feel disdain towards those driving market prices up. But that's my issue to deal with.

Best wishes...
Hi Larryi,
My objections were to (what I believe is) the crazy pricing. I even think ~$300 for a pair of 10m's is insane. I love the tubes dearly, but where does gouging end and fair value begin?

I am not used to the idea of rare tubes and the enormous prices they can command. I realize price will only go up as time progresses, and the tubes become more rare. Through my own experiences with 12ax7's, 6gh8's, and el34's, I do believe that the older tubes were better.

I think it is a seller's market, and am disappointed to see the free market capitalism envelope push so hard. But that's only my opinion, there are many valid arguments against my point of view! One of them is the very obvious supply and demand. Another is the arguable dearth of current production competition.

The thought that these were fakes did, of course, cross my mind. How would you return them if the midrange was grainy and top-end was shrill, then you discovered you could not rub off the markings with your finger tips? It seems to me to be too much of a risk to take at that price. I am in no way implying that they are fakes! I have no experience with the seller, and have nothing against him except the pricing of his tubes.

These may turn out to be fair market value, given the laws of the market. Of course, then I eat crow, as they say. But I have seen other markets where the price envelope is pushed to the extreme by a few, then that pushes the average to an artificially high level. That is what repulses me.

I have read the above comments. Thank you! All valid points.
Cheers.
Bicicyle_man, in fairness, I have seen "museum quality" TFK 803S's go for as much as $1400 a pair on eBay (before the financial meltdown!) They ARE rare, and if one is a collector (and has no intention of using them - which blows my mind ;-) I suppose . . . . . .

But if you were to do a little research as I did, purely out of curiosity (I wondered what a $1400 pair of 12AX7's must sound like?) you would probably discover as i did that the concensus was "nothing special"!

The only time I [almost] got badly burned buying NOS tubes (the seller took them back ;-) was when I paid a premium for some truly NEW NOS tubes and one was a complete dud. But nobody knew because no one had ever tried to use them! Oh yeah, the seller had tested and measured them, but not actually placed them in service in a component. From then on, I only buy ANOS (almost new old stock) tubes with at least a few hours on them. There's nothing like a 'track record' when it comes to tubes!
Bicycle Man,

The ebay price listing for the ECC803S is quite high, but, is there something else you object to about the listing? Are these fakes?

Whether or not a tube is the "best" is a matter of system synergy and taste. I found it a bit obnoxious for the poster to suggest there is any kind of audiophile consensus on the 803S, but, the price any decent tube of that type gets is a reflection of demand for that tube. Sure, collectors have driven up the price too, but, I bet quite a few are in actual use.

I do think the 803S is unique, in terms of its utter speed, impact of transients, and detail. I know it can sound lean and analytical in most setups, but, where it works well, I have not heard anything that can compare. It also has a reputation for having a very long life. The value of what this tube offers is in the eye of the beholder.

I am just trying to get some idea of whether you are raising objections to the tube itself, the crazy pricing, or the specifics of the particular ebay posting/poster.
Cruz123 - The Mullard reissues are garbage IME, and the Sovtek LPS are moderately better. I've found you get what you pay for when it comes to tubes. Finding used NOS tubes in good condition can save you some money, but still expect to pay quite a bit more than the inexpensive current tubes previously referenced.
Has anyone tried the Mullard Reissue 12ax7 and/or the new production Sovtek LPS 12ax7? They get good reviews over at Audio Asylum and the LPS's especially seem to have the rep of being exceptionally quiet. I've ordered some of each to try out in a VAC pre I just picked up. I thought I would try this route before blowing the inheritance on NOS.
Thanks, Nsgarch! It burned me up to see that auction. After a little thought, I have reached the conclusion that I won't let the likes of him upset me. If people are willing to pay the prices he asks, it is their problem. Thank you for your supportive comment.

Perhaps the synergies between different tubes and amps has to do with the electrical properties of the tubes and the circuits they are plugged into. This sounds like stating the obvious. But, maybe the effects of the parameters are more profound than theory or expectations suggest. It is an interesting phenomenon!
Tubes sound different in different preamps. Maybe someone can comment on the synergy of this.

I have a Jolida Envoy and a Symphonies, while TF ECC83's rank high in each, the Mullard 10M 12AX7 out shines everything in the Symphonies, but is not particularly interesting in the Envoy.
Bicycle_man, isn't that queen just too much!? It cracks me up every time I see his auctions!

Bob, I applaud your reminding us all of this:
. . . but making sure to go back and see if a change is ultimately an improvement, or just a change.
Human beings being the stimulation junkies we are, changes often seem 'better'. For at least a minute!!

Geary, I have also been cautioned about using 5751's if they would be in (active) RIAA circuits. Apparently passive RIAA circuits are not affected.

Neil
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Some POS from Singapore is trying to sell a pair of NOS ECC803S's for $1099.99 + shipping.

http://cgi.ebay.com/2XNOS-ECC803S-ECC83-12AX7-Telefunken-Bottom-Ulm_W0QQitemZ130310286752QQihZ003QQcategoryZ67816QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

MoFo!
Update, I had some good ears over this past weekend and we played with a few different things. We did try swapping out the 5751's for the Tung Sols.

The impression was that the RCA Black Blate 5751's were a bit more dynamic but ultimately too plummy and slower on the bottom end. The Tung Sol 12AX7's were clearer and cleaner and faster all around. The general consensus was to leave the Tung Sols in.

Well, that's what this hobby is all about. Trying different things from time to time, but making sure to go back and see if a change is ultimately an improvement, or just a change.

Enjoy,
Bob
Bob,
Jim H, most likely doesn't recommend 5751's in the Trumpet because the RIAA is passive and the tubes contribute to the equalization. That being said. I am no RIAA equalization
Nazi and use 5751's, which I think sound great, in my phono pre amp. I am building a Cornet2 and will try them there, well.

Cheers,
Geary
Bob, "ruggedized" (for the military) 5751's (especially the triple mica ones) are supposed to be great in phono and microphone preamps because of their extremly low noise and/or microphonics compared to a regular 12AX7. Something I can't really judge as mine are in an amplifier. However, they are definitely smoother (by which I mean less in-your-face grainy) than the 12AX7's I've tried; and the really good 5751's are more dynamic too. -- Neil
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I have a Hagerman Trumpet phono stage, and Jim Hagerman said not to use them over the 12AX7, but it sounds so much better. There was no reduction in gain that I noticed. In fact, it sounded louder because of the increased dynamics. It was also clearer but smoother on top. Could be a reduced noise floor. Don't know.

I do know that there was a very low level buzz in the Tung Sols that I was using before that is now gone with this 5751. Don't get me wrong, those Tung Sols are very, very good - a sweet sounding tube with clarity and kick.

I need to try the Tung Sol's in my preamp and see how they fare against the RCA Clear Tops I am using there now. Or perhaps try the 5751's in there and see if it betters everything all around or if they truly belong in the phono stage (I only have 1 pair, so a search for their best location is needed).

Bob
Bob, the RCA 5751 TMBP is my favorite 5751 (it's a REALLY tough call, but I still think I like it better than the Sylvania.)

I have mine in a Mac amp, but in a phono stage did you notice:
A. Any reduction in gain? Many are concerned about this, personally I don't think it would show up unless one is driving the tube over the brink!
B. Any (noticable) reduction in noise floor - you did say "clearer", so that might could be lower noise floor?
Just replaced my Tung Sol 12AX7's in my phono stage with the Black RCA 5751's. This is the way to go if you can handle the slightly different tube. More dynamics/punch on the bottom end, smoother on top and just clearer overall.

Bob
It seems many are raving about the RCA 12ax7 black longplates, but I've barely seen or heard a word about the RCA 12ax7 GRAY longplates. I've owned and listened to both varieties in my system. I just shook my head. I wound up selling the blackplates.
Larry, one day I just said, "this really sucks!" and I got some Q-Tips, gathered a few old European tubes that had almost no printing left, and set out to try every solvent I could think of to see if anything would spare the printing. Naphtha was IT. And no surprise really -- that's the only solvent dry cleaners will use on your clothes!

I should have noted that even the moisture in some peoples' skin can take off the printing, so it's best to handle those with really fragile (almost gone) labels with a clean cotton cloth or latex gloves before and after cleaning.
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Yes, it does appear that many older tube varieties have very fragile printing on them. My telefunken ECC83/12AX7s barely have any markings left, just from handling. I am fairly careful handling the ECC803S which were never used (cam in very nice looking boxes, though the cardboard has become somewhat fragile). My Bugle Boys also have somewhat fragile printing.

Because of all of this discussion, I did something I rarely do (being quite lazy), which is to switch out the ECC803S and replace them with the ECC83. Where my memory was that the ECC83 was more "muddled" sounding, that turned out to not exactly be the case. The ECC83 is not really more muddled or lacking in clarity, it is more the case of transients (initial attack of the note) being softened, as compared to the ECC803S. I still prefer the ECC803S, but again, the price differential is striking.

I should also mention that, in another friend's system, the Bugle Boys sounded terrific in the phono stage of a Hovland preamp -- so much more lively than the stock tube that came with the preamp.
B-man, we were all beginners once, and although people have to have their own learning experiences, it doesn't hurt to ive folks a little heads up.

As for current ('reissues') vs. NOS (honest people now call them ANOS = almost new old stock = slightly used old stock ;-) Honestly, slightly used is a better bet than brand new old stock because at least the slightly used are proven working. If I were buying expensive BRAND NEW old stock tubes, I'd make a deposit but then insist the seller
test and burn-in the tubes for a few hours before shipping them to me ;-)

As for their sound, the current issues aren't bad, and I'm sure they will slowly get better. The brands bought by the American fellow who owns New Sensor in russia are: Sovetek, Genalex Gold Lion, Electro Harmonix, Svetlana, Mullard, Tung Sol, and a few other I forgot. None of them are like the originals (internally) although some are built very substantially.

The real difference between the old and new is metalurgy. The old-timers who experimented for years and years cooking up new (secret and jealously guarded) plate coatings had no one to pass the secrets to when ss came along. So the craft died with them. They succeeded in achieving very high plate current at rated voltages that tubemakers today can only hope they'll get to one day.

As an example, a typical NOS Genalex GEC or Gold Lion had transconductance values (when new) of 10,000 umhos or more (that's the measure of a tube's gain). Today's best KT-88's, the Genalex or the Shuguang/Penta-Labs (the Penta is an exact copy of NOS tube) when they are brand new are 7000 to 7500. I have some USED NOS Genalex theat are 9000! So it's not so stupid to buy he older tubes and some of them have a sparkle to them than so far no current tubes can duplicate. Anyway that's the basic story. There's tons of history and lore available today at the click of a mouse.
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Thanks Nsgarch for watching out for me. I should have put a "just kidding" type statement after my first paragraph above. Sorry, my sense of humor can be pretty bad or twisted.

I have read articles on the Internet in my research about the counterfeits of the highly valued "NOS" tubes, and one of the first things they mention to look out for is labels that are tenacious and don't wash off.

Actually, as an aside, the counterfeits make me wonder about re-issues. Are they really built to spec of the original tubes, and with the same quality of workmanship? The burning question is, do they sound as good? Anyone have experience with them in comparison to the originals?

From the very first moment that I started cleaning my NOS tubes, I noticed how easily the labels came off. The labels were practically rubbing off in my latex-gloved fingers. And with isopropanol, they came off immediately (the labels, not my fingers). I immediately broke out my tube tester and Sharpie-brand marker, and numbered, tested and cataloged my tubes before cleaning the rest. I matched the tube number to the tube brand and measured specs. I am so happy I did that because now, years later, I can still identify tubes and match them.

Thanks for the tip about Herleen Holland, too. I will look out for them. I like the BB's so much that I am very curious to see if the other Amperex's sound as nice.

Thanks again for watching out for me so that I don't get ripped off -- there are many things I am naive about and it is great when decent people speak up!
B-man I've heard rumors (un-verified by me, mind you) that the BB's with the permanent labels (not the Amperex orange globes) might be fakes. I would suggest doing a bit of research first. I could be wrong of course, however I find "Trust but Verify" to be an excellent approach (in many areas of life actually!)

BTW, according to my techie friend Stephen Sank, any of the minitriodes that say Herleen Holland are out of the same Amperex factory? Just different labels/brands.
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Now you tell me! After I washed off those cool little bugle boys off my Bugle Boys! Should I just toss them and buy some of those more robust Bugle Boys where the bugle boy doesn't wash off?

Thanks for the information! I will give it a try.
I know none of you will believe this (until you try it!) but the best way to clean tubes, and especially European tubes with that delicate white printing, is naphtha (as in: Ronsonal lighter fluid.) Anything with even a hint of water in it (almost all alcohols, Win dex, etc) will dissolve the white paint, but not naphtha.
Hi Rodman,
They came with my Dynaco pre-amp. I bought it and a Stereo 70 from the son of an engineer who made it while he was in college in 1965. I don't believe he ever changed the tubes. The tubes test very well in my tube tester.

The tubes have the diamond in the glass inside the semi-circle of pins. There are number codes inside the diamonds (date codes I guess).

I have long since rubbed off the lettering while cleaning the tubes with isopropanol. But the diamonds are of course there as they are molded in the glass.
Actually I found the upper frequency detail softened and veiled by the Telefunkens in my system compared to Bucgle Boys and Mullards, including the 10ms.

This is with my Fisher 400c and Dynaco Pas3x pre-amps.

I did not have muddiness with the Tele's, just not the same upper frequency and timbral magic of the BB's and Mullards. Also, the latter two brands were more open and had wider and deeper soundstaging qualities.
Thanks Larry. Anybody else want to chime in?

I'm listening to horns today (recordings), so maybe that should be 'honk' in ;-)
I don't what is meant by the statement that 12AX7s are "grainy." I sometimes wonder if "grainy" is sort of the opposite of "fluid" or "smooth." Sometimes, what some others describe as smooth or fluid, I think of as being "soft" and a bit "muddy." The "muddy" quality I am talking about is a bump up in upper bass lower midrange that tends to obscure (or soften) upper frequency detail. Perhaps this detail is the "grain" being referred to; its hard to guess what these terms mean. So much is dependent on personal taste and system application, I don't think any generalizations can be made that one tube is better than another across the board. That is why, in my prior post, I emphasized the fact that my observations pertained to MY system.

One thing I forgot to mention in my prior post. For the Tron phonostage, the best alternative turned out to be Amperex Bugle Boys, at least in my friend's system (the consensus of several listeners). We did not try the ECC803S for this particular trial. I don't recall what current production tube the Tron came with, but, it is utter crap compared to the old alternatives we tried. The Tron was extremely sensitive to tube choice. I suppose this is a tribute to how revealing this phonostage can be.
RE what Larry just said about the premium TFK, I have a general 12AX7/5751 question/poll(?) for those familiar with both (hopefully, but not necessarily, in the same piece of equipment ;-)

In his famous "Tube Lore" article on AA, http://www.audioasylum.com/scripts/d.pl?audio/faq/joes-tubes.html Joe asserts that he could never really find a 12AX7 he liked. He lists some preferences, but compared to his favorite 5751's, he finds all 12AX7's "grainy" (I think his word was.)

I maaaybe understand what he means. However I've rolled many different 12AX/AT7's and 5751/6201 in my McIntosh MC275, and like Larry, I've learned that to have blanket prejudices/preferences may not lead to the best choice - my love for the GEC A2900 being a perfect example (I never would have tried it if I'd decided to only go with 6201's.)

So does anyone agree with Joe's take on the issue: that 5751's are better across the board than 12AX7's? Just curious ;-)
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In my phonostage (Viva Fono) I've tried a number of different 12AX7 variants. The Mullards sounded a bit veiled (muddy) for my particular application. In a friend's Tron phonostage, Mullards actually sounded oddly phasey.

I liked the sound of 5751s -- neutral, reasonably detailed and open on top. I did not notice a loss of gain, but, I wasn't looking at gain because gain and noise are not issues with my phonostage.

Telefunken 12AX7/ECC83s were also very good in my phonostage -- quite detailed, extended top and good harmonic density without being muddy sounding.

The Telefunken ECC803S is a very different animal from the other 12AX7s I tried -- incredible clarity and detail and explosive transients. It sounds a bit lean (less upper bass) and perhaps clinical, but, I made other minor compensating adjustments (primarily to VTA), and it is the very best tube for my application.

However, the ECC803S is WAY more expensive than the competition. For the money, a good pair of 5751s are hard to beat.
Hi Clipper,
I have the BB 12ax7's in the phono stage, a BB 12at7 nearest the transformer, 2 Sylvania 12at7's near the can caps, and an unknown old stock 7025 in between (near the 6v4 rectifier).

The pre-amp sounds fine on tuner and both aux's, and of course, super fine on phono. I have repaired mine as many of the old Wima caps have dried out and wasted away.

I have also used the BB's in my Dynaco Pas3x and have found the same results as I previously described. The Fisher is not as forward sounding as the Dynaco, but it is, oh, so much sweeter! I was happy to see some Fishers selling on ebay for more than $450 in the last few months! As I recall, one of those was the 400-cx, which has a better following, but the other was a plain old 400-c. I have the 400-c. I like it and can't wait to get my Koetsu re-done -- should be mid-range luscious delight!
Sounds like me. I should have stocked up on TungSol 6SN7GT/VT-231 Round Plates($50.00 ea, when I fell in love with them) while I had the chance. I was going to use three 6201's as phase splitter/drivers, but gave up on that amp after getting burned by the transformer builder(paid for, never received). Nothing I own now uses 6201's, so- I've never even heard these.
Rodman, I danced around with various 6201's after trying some 'normal' TFK and RCA 12AT7's (which weren't bad actually) and also a quad of Mullard CV4024's (which for some reason I didn't really like; which surprised me after all the good things I'd heard), anyway, I liked the Sylvania 6201's a lot (the 2-mica BP gold pins) but the ones I like best (they're not 6201's) are the GEC A2900 (or CV6091 military designation.) These are amazing tubes; really powerful, but smooth as silk, like Gold Lion KT-88's! I was going to try and put together a spare quad but I think the word has got out (damn!) I got my first pair for $85 six months ago, and now they're over $200!! Check the mutual conductance values on these babies, and you'll see what I mean by 'powerful'! http://cgi.ebay.com/2XNOS-A2900-CV6091-12AT7-ECC81-GEC-Great-Britain_W0QQitemZ140298633321QQcmdZViewItemQQptZVintage_Electronics_R2?hash=item140298633321&_trksid=p3286.c0.m14&_trkparms=72%3A1234%7C66%3A2%7C65%3A12%7C39%3A1%7C240%3A1318%7C301%3A1%7C293%3A1%7C294%3A50
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Bicycle Man,

Thanks for your insight. I know exactly what you mean about the highs. They have a definite edge to them in my setup right now. The bass has been fine for me, I think mostly in part due to my Forte II speakers.

What positions do you have the BB in? Also, I forget, did you end up trying any 5751s?

Thanks,
-Clipper
Mr N- Since you mentioned 6201's: I bought four for an amp I was building a few years back, but never used them. I sent two to an AudiogoNer to try, and he bought them. I've still got the other pair, if anyone wants to try them out(free-no strings). Gold pins, triple mica, but I don't know who actually made them(They're labeled Tele ECC801S, but they're not- no diamond).
Rodman, when did I ever say they were the same tube? Anyway, if you're talking about the (little used) "amplification factor" curve, yes there is a slight difference, but if you look at the transconductance curves (Gm), the standard measure of gain, the two are almost identical, in fact the 5751 shown in the curves I saw was actually a little higher. Anyway, no (tube) circuit designer in his/her right mind would drive a given tube into that portion of its operating range in the first place.

Having said that, it's well-known that ARC drives their (power) tubes quite hard while McIntosh is quite easy on tubes; which is why you've yet to see a Mac tube amp with mechanical ventilation ;-)
I am using a Fisher 400 pre-amp now with Bugle Boy 12ax7's now and am very, very happy with them. This is the pre-amp I was using when I exchanged the JJ's for the BB's recently. With the JJ's I honestly thought I needed a sub-woofer, and when I changed to BB's I realized I didn't. The sound stayed crystal clear, the highs lost the edginess that I heard with the JJ's, the mid-range blossomed into sweetness, and the bass filled out the missing void.

I would recommend Bugle Boy's. The Orange Globe labeled Amperex tubes sound tempting to me. Telefunken's are definitely a step up from JJ's, but I prefer the BB's. The Tele's are very good at everything but miss the magic of the BB's.

For less money, I bet almost all NOS 12ax7's will beat out current production jobs. I have been satisfied with RCA and Sylvania NOS 12ax7's over the JJ's.

Give the tubes time to break-in before jumping to a conclusion. The JJ's became sweeter over time, but in my opinion could not stand up to the NOS tubes that I have.

Happy listening after your search!
I appreciate the input guys.

So it sounds like the 5751s wouldn't really be necessary for me then? I am just trying to figure out what tubes I should try in my Fisher. I am really curious to experiment and see if I can get a better sound than the JJs are making right now.

Thanks
-Clipper
Then you disagree, not with me, but the specifications of the tube itself: (http://www.boiaudioworks.com/5751) (http://www.tubedepot.com/5751.html) paragraph 5 of this page:(http://www.guitaramplifierblueprinting.com/files/Phaseinverter.pdf) (http://www.guitaramplifierblueprinting.com/Tube/5751.pdf) (http://www.guitaramplifierblueprinting.com/files/GE-12AX7.pdf) compare the plate dissipation/transconductance/plate resistance of the 12AX7 and 5751. They are different because the 5751 in not a 12AX7, and has less gain as a result of it's design.
I disagree that you'll need to compensate for the 5751's slightly less gain; because that difference doesn't really occur until past the normal operating range on the two tubes' curves. Most people can't hear any difference, and the military (who originally requested a 'ruggedized' 12AX7) wouldn't have traded that requirement for a loss in performance when they replaced their 12AX7's.

As for tone, that really depends on the specific tube and to a (lesser) degree on the make of amp. I specify 'amp' because that's where the tube produces the most gain and so the tonal qualities are most obvious. In a preamp, what you are looking for is low noise -- especially in tube phonostages where a 5751 might be a plus.

I don't have tube preamp/phonostages, but the majority of my friends with McIntosh tube preamps (with tube phonostages) seem to have settled with Telefunken AX's and AT's over the stock Chinese tubes, and haven't ventured much beyond that. People with hissy tube phonostages who can't find a quiet 12AX7 and/or 12AT7 should definitely try 3-mica 5751's and/or 6201's (and tell us what happens please ;-)
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Clipper- You'll have to turn your volume control up a bit to get the same SPLs with the 5751, as they have about 30% less gain than 12AX7s. Their "tone" is also a bit more laid back(richer/smoother/warmer-more 2nd order harmonics) than most 12AX7s, if that's what you're looking for.
I am trying to find some tubes to replace the six JJ 12AX7s in my Fisher 400. I am wondering if you guys have any suggestions? They way everyone is talking I might be wise to try some 5751s in there. Any input would be greatly appreciated.

Thanks,
-Clipper
Thanks Rodman! I have read good things about the Winged C el34's. The National el34's look nice, too. Great information!

I use the 12ax7's in the pre-amp phono stage.

Cheers!
To quote Ivor Tiefenbrun(founder of Linn Products), "If you gaven't heard it, you have no opinion."
Right! And good luck getting anyone to send you a demo tube so you can form an 'opinion'!

I'm more interested in how these TechTubes will sound. They should be ready (finally) to release them this month:
http://www.techtubevalves.com/
The have a new (for 9-pins) internal structure that uses CRT technology. And at $30 a pop (or so) I'd be willing to try a couple ;-)
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To quote Bicycle man, "It's a pity to think that good current production 12ax7's are so lame -- what to do when it is time to buy new tubes?", which is what I was responding to. Where in that post was "saving money" mentioned again? FYI: The EAT comes with the cooler/damper attached, and you'll ALWAYS see them advertised/pictured that way. To quote Ivor Tiefenbrun(founder of Linn Products), "If you gaven't heard it, you have no opinion."