No one said that. What certainly IS true is that one is not likely to be better than another across all circuits. What is also true is that the variations among each type are usually greater than the variations between the mean performance of each type. What is also true is that these differences are far smaller than the differences one can accomplish by optimizing the circuit. And what's also true is that the characterization of one type as "warm and giving" and another as "incisive and tight" absent specific context and REAL listening comparisons is audiophile nonsense.
What is also true is that there's money involved in the stamp collecting game, with lots of stories to go with it.
As a DIY tube builder I'm a relative neophyte, but as a owner/consumer of lots of tube equipment over the past decades I've yet to hear anything a so-called professional medical instrument grade vintage NOS 1960s Telefunken 12AX7 ($200 per tube if you believe some current valuations) can do that my $8.95 Realistic Lifetime 12AX7 (Made in Japan, circa 1970 by the way) doesn't do just as well.
This statement implies no difference, as I read it. "Just as well". So actually, someone did say it.
As to that second statement, how are REAL listening comparisons nonsense? It seems your saying that comparing two tubes by listening to them yields no difference. Is that what you meant?
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No, I didn't say that. If you get essentially no measured difference between a circuit with tube A in it and the same circuit with tube B in it (we're talking about hifi now, instrument amps have some other complications), then casual open listening is likely to give you spurious results. Listening to a cut, then powering everything down, swapping out tubes, warming things back up, then listening again is a sure way to come up with incorrect results. Aural memory of subtle differences (and that's what we're talking about here) is very short, on the order of seconds. Plugging stuff in and out introduces another set of variables.
OK, now your meaning is clear.
Memory is admittedly a little unreliable at times. I think it has to do with what level of discrimination your are attempting.
For an extreme example, if you sat down and listened to one song on a boombox, then 10 minutes later listened to the same song on your main stereo system, clearly the difference is obvious and your memory is quite reliable.
I agree that subtle differences are harder.
What I do, is I have 5-6 songs that I regard as my test songs. What I mean is, that I have heard these songs countless times. I am familiar with all their nuances. Anytime I change something I put on one or several of these songs. My memory of them is strongly imprinted to how I am used to hearing them. Consequently, I am much more apt to notice if something has changed.
I have used this method to compare different versions of albums, say a remaster compared to the original. Admittedly, sometimes they are so close I am not sure of the differences. At other times, after the first 30 seconds, the differences are obvious.
I suppose it comes down to how good your memory is, how familiar you are with the material you are comparing, and how thin the slice of difference is your trying to discern.
Yes, but if you're human, subtle auditory differences (or for that matter, subtle sensory differences of any type) just can't be reliably distinguished unless the stimuli are close together (seconds). You can demonstrate that to yourself pretty easily. Record two tracks of the same material, but with a 0.5dB difference in level. If you do a fast ABX comparison, you can reliably distinguish one from the other by listening alone. Now, wait 5 minutes between each comparison. I don't care how careful you are or how well you know the music or your system, you won't be able to tell one from the other. You can use the ABX facility in Foobar to set this up.
The point I tried to make was that in regards to a abx test, if "a" is firmly planted in your mind (by countless listening of it), and now your hearing "b", you can compare the two in real time in your mind. Your not relying exclusively on what you heard 5 minutes ago, but rather a firm memory of many accumulated listening sessions.
Vast familiarity with "a" in the same environment, everything else being equal, is the key here.
Your examples and point has much more merit in the case whereby the song your comparing is an unfamiliar one. Or if you are at someone elses house doing a abx test and their system isnt familiar. Or your at the stereo shop auditioning speakers whereby all the equipment behind the new speaker is unfamiliar.
I can agree to disagree with you here in any case
Unfortunately, a huge body of serious sensory research comes to a different conclusion.
Try my little experiment- fix your mind as well as you can, you won't be able to reliably distinguish A from B, even though in rapidly switched comparison, it's not at all difficult. Use your system, your song, your ears, and (here's the key) your human brain.
Try my little experiment- fix your mind as well as you can, you won't be able to reliably distinguish A from B, even though in rapidly switched comparison, it's not at all difficult. Use your system, your song, your ears, and (here's the key) your human brain.
I also find changing tone capacitor values (+ PIO vs the other types) can get you pretty darn close to a sound that is pleasing to the ears. It always involves trying different things.
From the source of the sound (CD Record Radio etc) all the way through to the speakers. Time consuming and expensive.
From the source of the sound (CD Record Radio etc) all the way through to the speakers. Time consuming and expensive.
If a mod wants to change it to:
12ax7a & 12at7 recommendations
That might be more descriptive.
Perhaps a good question to ask at this point in the thread is:
For those that have swapped a 12ax7 to a 12at7, or visa versa, what differences did you notice? 5751?
*lets limit answers to non-guitar amps
*please also specify what piece of equipment you did this in and what was the original recommended tube for that unit
For those that have swapped a 12ax7 to a 12at7, or visa versa, what differences did you notice? 5751?
*lets limit answers to non-guitar amps
*please also specify what piece of equipment you did this in and what was the original recommended tube for that unit
I'd go with what you have!
The tubes you listed are not expensive. in fact when I tube rolled my Jolida I went with
the Jan Phillips 12at7wc $12.95 each. The 12ax7a I bought was Gold ECC83-S $21.95 each. The JJECC83-S are nice sounding preamp tubes for the money.
This combination really sounds good!
Good Luck!
The tubes you listed are not expensive. in fact when I tube rolled my Jolida I went with
the Jan Phillips 12at7wc $12.95 each. The 12ax7a I bought was Gold ECC83-S $21.95 each. The JJECC83-S are nice sounding preamp tubes for the money.
This combination really sounds good!
Good Luck!
I didn't swap a 12AT7 for a 12AX7A! My amplifier uses both. The 12AX7 for a preamp, 12AT7 for a driver, and the EL34 for an output tube.
I suggested using the JJ Gold ECC83-S. for his amp. I shouldn't have mentioned that the combination sounds really good. oops. it's a preamp.
well do yourself a favor jim1961.. get the JJ Gold ECC83-S It's a big bang for the buck!
I use them as the preamp in my Jolida and also in my MiniWatt N3
I suggested using the JJ Gold ECC83-S. for his amp. I shouldn't have mentioned that the combination sounds really good. oops. it's a preamp.
well do yourself a favor jim1961.. get the JJ Gold ECC83-S It's a big bang for the buck!
I use them as the preamp in my Jolida and also in my MiniWatt N3
I asked for people to share their experiences in swapping, not whether they approve of it or not. The later has been covered already.
btw...there are scores of tales out on the net of people that do.
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No shortage of fairy tales on the net
I once believed that the 12AX7 simply had to be a great candidate for a phono-stage, after all they were ubiquitous in early phono-stages. as DIY builds on the net and even among the so-called boutique phono-stages one finds lining the shelves of Audiophile? outlets.Luckily, the DIY gang here dissuaded me of the notion that the 12AX7 was the best way to go based on some pretty irrefutable evidence (tube characteristics) and years of experience building their own phono stages.
Old Harman Hosner, Avery Fisher and company, knew what they were doing in this regard. When they specified a 12AT7, 12AY7, 12AU7 or 12AX7 for a particular stage they weren't being cavalier..in every case where I substituted a variant for the intended tube in pre-amps, power amps and tuners...the performance of the equipment took a steep nose dive.
DF96 is correct in saying "The 12AT7 and 12AX7 are so different that only in a guitar amp could they possibly be considered as candidates for a swap."
Guitarists have a set of sonic objectives
that are generally in-congruent with Hi-Fi audio objectives.
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