Preamp Tube Experts -- Should I buy $$$ NOS 12ax7 ??

[jibreel]

Been through multiple preamps and amps, both SS and tube. Buy, try and sell [ usually at a loss ].

I am now VERY happy with my current rig. Hughes and Kettner BATT tube preamp into and through a TC Classic 450 head. 606 cab with a 3015 and an Acoustic Image cab with a downward firing 10" woofer and a 5" mid. [ Soon to be joined by an Audiokinesis Thunderchild 12AE !! ].

The BATT is amazing for tube pre sound [ I have two of them]. It beat out Alembic, Kern and TE preamps for me. The old school voiced 450 gives me some modern SS sound that I also like in the blend.

Because Gas is unrelenting, I am now pointing my credit card at higher end, perhaps NOS 12ax7 preamp tubes.

Firstly, unlike some other preamp/amps, the BATT is VERY much effected by different preamp tubes. Very noticeable differences.

I have a JJ in one and an EH in the other. The JJ is winning right now as the EH is a little dark.

I guess I am just wondering if there is " more ". More harmonic depth, fullness and fidelity.

Given how advanced my Gas is, I am willing to spend up to $ 175.00 or so but would be happy to spend $60.00.

So, any suggestions on higher end 12ax7 tubes would be appreciated. Or not-so-expensive tubes. Or new stock tubes. Thanks !!



The power tube in the BATT is bypassed for my use so is of no consequence.

[hyp.spec]

From your post, sounds like to me you should just keep running with what you have... no point in wasting $175 on something you may not end up enjoying!

[chuck3]

without knowing more about your gigging situations, there's no way to advise. If you're not gigging, there's no need to advise, just do what you want but no need to spend xtra $.

I like your overall approach. I play a passive Fender J into an EBS Valvedrive tube preamp, into a Genz Benz Shuttle 6.0, which has one tube, into a Schroeder 1212, which has one down-firing 12 plus the other 12. It's a pretty robust and tube-y rig for mid-size bar gigs which is mostly what I play.

[jibreel]

I guess I am just wondering if there is " more ". More harmonic depth, fullness and fidelity.

I play in small venues and my living room. It is my living room where I want it to sound as good as possible. I guess this is kind of like an obsessive audiophile with his stereo system.

I know there is only so much one tube can do and only so much that one tube can do given the electronic system.

It really is an indulgence of sorts given that it sounds as good as is does already.

However, I do want to indulge some.

[bongomania]

IMO/IME there is not enough "predictability" just going by brand names, eras, etc. Old tubes have usually drifted from their original spec, so you can take three of "the same" tube (e.g. 1961 Amperex Bugle Boys) and they will likely not sound the same.

So the best thing is just to buy whatever tickles your fancy, and try it out. Eventually you'll hit the gem you were looking for.

Believe it or not, in my days as a bongo player I did the same thing with cowbells. I bought dozens of cowbells of all eras and origins, until I found "the one". I will probably be buried with that cowbell.

One of the best-sounding 12AX7's I've ever found was a modern Russian 12AX7LPS, not even mil spec, that cost me like $5.

[jibreel]

Originally Posted by bongomania

IMO/IME there is not enough "predictability" just going by brand names, eras, etc. Old tubes have usually drifted from their original spec, so you can take three of "the same" tube (e.g. 1961 Amperex Bugle Boys) and they will likely not sound the same.

So the best thing is just to buy whatever tickles your fancy, and try it out. Eventually you'll hit the gem you were looking for.

Believe it or not, in my days as a bongo player I did the same thing with cowbells. I bought dozens of cowbells of all eras and origins, until I found "the one". I will probably be buried with that cowbell.

One of the best-sounding 12AX7's I've ever found was a modern Russian 12AX7LPS, not even mil spec, that cost me like $5.

I am sure you are right. I was just kind of hoping there was some sort of formulaic approach like: if the JJ tube sounds good in that rig, and you like the tube pre and SS amp sound, then xxxx tube at $60.00 will sound great and xxxx tube at $120.00 will sound Really great.

Guess I will just have to keep the great tradition going of buy, try and sell [ at a loss ]. Gas

[MAMMOTHvolume]

$175 will buy you alot of valves, why not buy a bunch of mil spec etc ones and try them all out and report back to us!

[zombywoof5050]

When I compared JJ's with Telefunkens in my Alembic F-2B, I thought the Telefunkens were a great improvement. IMO the Telefunkens were well worth the $67ea that I paid for them.

[Handyman]

I wouldn't bother, there are plenty of great new production 12ax7 tubes that can be had for $15 or less. Just because someone's willing to shell out big bucks for a particular NOS tube doesn't mean its going so give you the sound you want in your particular application.

[staindbass]

if the current production preamp tubes were just as good, vintage prices would drop through the floor real quick. they are not. some current production power tubes (6l6, el34 ect) are catching up to to the vintage tubes in terms of sound quality. preamp tubes add more to the sonic signature than power tubes. thats why the powertubes are catching up and the preamp tubes are not. if you google audio asylum (where i hang out) and search 12ax7 in the tubes section, you will find tons of opinions. telefunken 12ax7 smooth plate are supposed to be the clearest acroos the frequency range. the ribbed plates put a slight emphasis on warmth. mullards and known for strong bass. rca has a good even tone all around(the blackplates). black plates are from the 40-late 50's and were made with higher quality materials and more support rods for less microphonics and other stuff. the 5751 raytheon is a great higher quality substitution for a 12ax7. i use them in my vintage hifi at home anywhere there is a 12ax7. the 5751 sylvania with triple mica are very good too. for bass, i would try a 12ax7 rca blackplate, and a mullard. if you dont notice much of a difference, its not worth investigating further.if you notice, spring for a telefunken. good thing is, you can still sell them for what you paid since they are already used johnny a. staind

[Handyman]

Originally Posted by staindbass

if the current production preamp tubes were just as good, vintage prices would drop through the floor real quick. they are not.

I'll have to disagree with your reasoning here. See vintage bass prices as a good counter example.

[jibreel]

Originally Posted by staindbass

if the current production preamp tubes were just as good, vintage prices would drop through the floor real quick. they are not. some current production power tubes (6l6, el34 ect) are catching up to to the vintage tubes in terms of sound quality. preamp tubes add more to the sonic signature than power tubes. thats why the powertubes are catching up and the preamp tubes are not. if you google audio asylum (where i hang out) and search 12ax7 in the tubes section, you will find tons of opinions. telefunken 12ax7 smooth plate are supposed to be the clearest acroos the frequency range. the ribbed plates put a slight emphasis on warmth. mullards and known for strong bass. rca has a good even tone all around(the blackplates). black plates are from the 40-late 50's and were made with higher quality materials and more support rods for less microphonics and other stuff. the 5751 raytheon is a great higher quality substitution for a 12ax7. i use them in my vintage hifi at home anywhere there is a 12ax7. the 5751 sylvania with triple mica are very good too. for bass, i would try a 12ax7 rca blackplate, and a mullard. if you dont notice much of a difference, its not worth investigating further.if you notice, spring for a telefunken. good thing is, you can still sell them for what you paid since they are already used johnny a. staind

Thanks for these very specific examples. I will give some a try and report back.

[ddbassGA]

I'm kinda just the opposite. I have an arsenal of old tube amps and a couple of tube-pre hybrid heads. I look for the best bang for the buck, not looking to spend any more than I have to. I'm very interested in good quality vintage tubes if I can find them at a good price. For power tubes, new JJ seem to work well, but I just got a NOS duet of RCA 7027a for about the same price and some NOS USA Sylvania made Groove Tubes for not much more.

For preamp tubes, I want to know what is the best 12AX7 (and other preamp tube) I can buy for the money? Say $20 ($15-25)? I just can't envision spending $50 on a 12ax7. My B-15, V4, Bassman, ProReverb are not hi-fi amps. But I want a good accurate tube with no microphonics.

[metron]

Eh. Tube performance critiques must be within the context of specific circuits otherwise you arent getting the full picture, just generalities that may or may not apply when you throw that nos tube in your h&k. Its at least partly a guess and check process unless you have a tube tester and knowledge of circuit analysis and/or design principles or you have comments from someone who has swapped tubes in your piece of gear.

[Scutterflux]

I agree with staindbass and handyman. First tube that came to mind for me for you was a mullard long plate (deep in bass and 3d soundstageing, kinda have a magic) and 2nd was RCA, however I was thinking of the rca 7025 grey plate (Good pleasing warm harmonic tone) maybe because I havn't tried the blackplate.
My comments on the Telefunken smooth plate (super tight bass, detailed and a bit of a crispy white fuzzyness),
You could try some amperex, those seem popular I havn't tried yet. You could also try a philips, I really liked them.
I've not tried the Raytheon 5751 but my experience with most 5751's is they are darker, with the exception IME of tungsol (smooth clear and broad) and greyplate 2-mica phillips and sylvania (pretty well same tube these are crispy tight and thick). But if you want to try dark and greassy, I really like the GE 3 mica black plate 5751 which is relatively similar to the Sylvania 3mbp, but a little cheaper.
New Production, I like JJ's, I really havn't tried too many newer tubes, but allot of guys are sayin they like the Sovtek LPS, Tungsol RI, and Mullard RI tubes, better than JJ's, so I'm itching to try those out within the next year or so.
This is a fun, and nearly useless hobby, it's mostly for oneself as most people will not notice any change in tone, but I do, and that's what counts for me. Have fun!

[Scutterflux]

I also agree with metron, my experience is generalities based on only 3 cicuits I've tried tube swapping with. Some circuits take some tubes better than others with more or less effect on sound etc.....

[astrah]

Bear in mind that vacuum tubes were the state of the art in electronics for well over 60 years, and during that time tube manufacturers poured the equivalent of billions of dollars of R&D funds into the development of their products. In the 80’s the western manufacturers sold the manufacturing apparatus to the Russian and Chinese companies, but did not sell the secrets and patents behind the metallurgics or the evacuation process with the equipment. Those are long gone now, as they were highly classified trade secrets, and everyone with first hand knowledge of them is likely dead now. Those secrets were highly contributory to the way those tubes sounded at the time. And since the new owners did not possess them, they started pretty much from scratch. At their peak, US and European tube manufacturers sold many millions of tubes per year, as just about everything electronic was reliant on them, thus they had pretty substantial budgets to improve their products. How many tubes are sold now by the Chinese and Russian manufacturers? I would guess a very small fraction of that number. Thus how much money do they have available to improve their products?
Every tube amplifier will have different sonic characteristics. Thus, every type of tube tried in an amp will have a unique sonic signature that is specific to that amp design. I tried many new, old USA, and old European tubes before I found the magic tubes for my vintage Ampeg, but those tubes were not the appropriate tube for what I wanted out of my Eden. (Notice I did not say NOS. You are extremely unlikely to find a true NOS tube out there now. Nearly all will be used to some degree.) That took even more research and experimentation . But at no time did I ever encounter a Russian or Chinese tube that came close to the sonic characteristics that make the older US and European tubes really special. The new tubes may be louder, but louder is not better by any stretch of the imagination. I have never heard a new tube that can achieve the amazing “3D” effect of a Mullard Blackburn when it starts clipping, or the glassy sheen type of warmth you get out of a smooth plate Telefunken.
Good luck in your search, but be warned, it will get expensive. The price of older tubes has gone orbital in the last few years, and they will continue to escalate exponentially in the future.

[teleharmonium]

It's hard to be specific without more info. So to throw out a few benchmarks; if you want the best possible clean sound, don't need particularly high output, and especially if the preamp has a tendency to be noisy, a real Telefunken is great. The new production Tesla ECC803S is not a bad alternative for less money.

If you want the most output and coloration, that would probably be an RFT. RFTs sometimes have big gain differences between one section to another - which might be bad or good depending on how the tube is used in the circuit and the sound you are going for. High output with a little more balanced sound would be an old Sylvania.

If you want to really clean it up, you can try an old 5751 or even 12AU7/ECC82 or 12AT7/ECC81. These are significantly lower in gain; however they have other differences as well (impedance), which make them work better as real world 12AX7 substitutes than the amplification factor rating would suggest.

If you are trying to finesse the midrange eq one way or the other using the preamp tube choice, it can be done but you'll probably need to try a lot of different tubes. I would probably start with some sort of old Philips/Mullard/etc tube.

[jibreel]

Well guys,
This is some great information. I may have to step up to the plate and buy 4 or 5 high end tubes and A/B them. I would record the tests. Let me ponder this for a bit. It would take 1-2 weeks to have them get here.

Thanks again

[Passinwind]

Originally Posted by jibreel

I guess I am just wondering if there is " more ". More harmonic depth, fullness and fidelity.

Maybe, but personally I'd start with the opamps, not the tube.