There is certainly a baseball-card-collector mentality about it. In practice, microphonics and noise aside, there's much more to be gained by optimizing topologies and operating points than trading baseball cards. But that's generally beyond the capabilities of most, so the plug-it-in-and-rave mentality takes over (I should point out that John Atwood has one of the deepest insights into tube types and topologies of anyone I know).
Rule of thumb: the dominant factor in sound is whatever was the last thing changed.
Rule of thumb: the dominant factor in sound is whatever was the last thing changed.
Meh Gordy, we all need a dose of reality, stay !
I support that tubes don't have a sound. I observed some have lower noise, better quality and slightly different parameters (this is very small variations). I don't believe a certain tube will sound bright or warm; it's all in the circuit!
Also I want to add: be price-wise!!! The best fancy tube in an ordinary tube amp is money wasted. If you have a 50k system then yes going after the 'best' tube in one category is good. Then again 99 % of amps have flaws
changing the tube can just be a temporary placebo!
I support that tubes don't have a sound. I observed some have lower noise, better quality and slightly different parameters (this is very small variations). I don't believe a certain tube will sound bright or warm; it's all in the circuit!
Also I want to add: be price-wise!!! The best fancy tube in an ordinary tube amp is money wasted. If you have a 50k system then yes going after the 'best' tube in one category is good. Then again 99 % of amps have flaws
changing the tube can just be a temporary placebo!
Re: Re: Re: Re: Re: Recommend me a warm, smooth sounding 6922, 6DJ8, ECC88 or equivalent
That said, good instantiations of it are actually quite listenable to me. Especially after taming any (likely) oscillations via the grid-stoppers recommendation. Designer Alan Wright reportedly seems to employ them well, for example.
(Which if accepted, would mean logically that different brands do effectively have different sonic flavours)
Sure the sound changes when you alter circuit parameters like Va and bias, etc. (well 'duh!''). But each tube brand still seems to retain a sonic fingerprint of its own (I'll save you the trouble and add...) to me.
It's not sentiment if it's based on repeated observation - one that I believe I could replicate under double-blind conditions (given a known, suitable, Hi-Fi system)
Further, music is an inherently subjective and emotional pursuit. Electrical engineering is a fine hobby in it's own right, but if the subjective component of the musical experience isn't important to you, then why are you here in a tube forum?!
Sure there are wack-jobs with their magic stones and such. (OT: This parody site is a hoot!). But is this something that's really that hard to believe? If a system has "a sound" due to it's components and circuit topology, then some of "that sound" could come from the parts themselves. Sure the circuit is where the action is, but that fact doesn't invalidate the forgoing -- heaven forbid; it's even something which you can even try out for yourself at home!
Actually, the 6DJ8 family is generally known to have a higher preponderance of odd order Harmonics relative to the more auraly pleasing even orders. Thus John could actually be right here, Gordy. It certainly correlates with my own experience of the family as generally having a subtle upper mid-range 'glare'.Gordy said:
That said, good instantiations of it are actually quite listenable to me. Especially after taming any (likely) oscillations via the grid-stoppers recommendation. Designer Alan Wright reportedly seems to employ them well, for example.
Well, it's funny that all the same brands out-of-the-box seem to display the same "differences in tolerances" then.Gordy said:
(Which if accepted, would mean logically that different brands do effectively have different sonic flavours)
I don't believe it because others say so, I believe it because I've demonstrated it to myself to my own satisfaction. I don't gain popularity out of it (witness this thread) and live by myself so I also don't have to answer to anyone else (including my zero audiophile friends -- though I do know a couple of people with studios)Gordy said:
Sure the sound changes when you alter circuit parameters like Va and bias, etc. (well 'duh!''). But each tube brand still seems to retain a sonic fingerprint of its own (I'll save you the trouble and add...) to me.
Gordy said:
It's not sentiment if it's based on repeated observation - one that I believe I could replicate under double-blind conditions (given a known, suitable, Hi-Fi system)
Further, music is an inherently subjective and emotional pursuit. Electrical engineering is a fine hobby in it's own right, but if the subjective component of the musical experience isn't important to you, then why are you here in a tube forum?!
THAT's WHY I'M HERE !Gordy said:
I suspect you are (were) bothering because you sincerely believe that this is all bunkum and are trying to save/steer others towards the path of rationality. I actually think that's commendable and is one reason that the tone of your posts have not been offensive to me. Because there was this time when I believed exactly the same thing...Gordy said:
Sure there are wack-jobs with their magic stones and such. (OT: This parody site is a hoot!). But is this something that's really that hard to believe? If a system has "a sound" due to it's components and circuit topology, then some of "that sound" could come from the parts themselves. Sure the circuit is where the action is, but that fact doesn't invalidate the forgoing -- heaven forbid; it's even something which you can even try out for yourself at home!
Re: Re: Re: Re: Re: Re: Recommend me a warm, smooth sounding 6922, 6DJ8, ECC88 or equivalent
Hi Majestic, nice to see you here!
Actually, do you have an equipment to see the specter? Try to get higher preponderance of odd order Harmonics relative to the more auraly pleasing even orders from any tube used as a cathode follower. It is impossible because no matter which tube is used a cathode follower is an asymmetrical by definition device that can't cancel even order harmonics in any case.
Majestic said:
Hi Majestic, nice to see you here!
Actually, do you have an equipment to see the specter? Try to get higher preponderance of odd order Harmonics relative to the more auraly pleasing even orders from any tube used as a cathode follower. It is impossible because no matter which tube is used a cathode follower is an asymmetrical by definition device that can't cancel even order harmonics in any case.
What kind of sicko do you take me for?!mach1 said:
behind closed doors and not in front of the children I hope
SY said:
That's a fair call to make on me, SY.
But given the paucity of legitimate data in this area however, that mightn't be too easy.
Firstly, there is my own subjective listening impressions of over 20 different 6DJ8 types, also backed up in subjective kind by John Atkinson, as per prior postings of his own.
Secondly, an article in Vacuum Tube Valley, Issue 7 by Eric Barbour which purported to measure the 6DJ8's 3rd harmonic at between 50% and 100% of its 2nd harmonic.
Thirdly the article by Roger Modjeski questioning the suitability of 6DJ8's for audio -- though further questions ended up being asked such as to whether he had real 6DJ8's or something like rebranded 6ES8/ECC189's
Fourthly, the article by some guy calling himself "by Me(tm) cynic {104267.2346@compuserve.com}" surveying the "Common Audio Preamp Tubes" (back in 1996) where he said that "{...} I tried 4 Amperex "bugle boy" samples for this article, and they were remarkably consistent. This to me, is a bad sign. I rarely see a tube with such a weird characteristic. The result is a tube that sounds like a transistor to me and a cheap one at that. I detect not a drop of euphony, but plenty of dry grating bones. This is loudly proclaimed by 'gurus' to be the most detailed tube of all."
For the record, I've so far found the rest of his calls (ok, well i haven't tried all of them yet...) to be rather accurate (ie personally verifiable), though I have some quibbles about his 'optimal' operating points used during his tests. (let alone whether his own 6DJ8 was properly grid-stoppered).
However, I can no longer find a copy of this article on the net to link to, but I would be happy to scan and send you (and anyone else) a copy of his article for your own assessment.
Finally, in your own defense, (believe it or not -- hey, I'm just trying to be honest here!) Allen Wright threw down the gauntlet on the 6DJ8 in some of his own designs a couple of years ago on AA. The 6DJ8 was designed originally for cascode use, so I'm not all that surprised that Allen was able to wring such performance from it in his circuits. It does tend sound good when used well (to my own ears).
He very clearly had 6ES8. When I get home from work tonight, I'll see if my lab notebook is unpacked (we just moved) and post some more rigorous data on a range of samples in my usual test configuration (LED bias, CCS plate load, consistent with distortion data presented by Morgan Jones in "Valve Amplifiers" 3rd ed).
In the meantime, I've posted spectra of my open-loop phono preamp here a few times- the distortion is dominated by the second stage tube, an ECC88, and the third and higher is nowhere to be seen at (IIRC) 7V output. 2nd is 0.05% or so, depending on the version used (CCa was the best, 6KN8 was the worst).
I don't know what circuit Barbour used, but if I saw 3rd only 6dB down from second, I'd be doing some troubleshooting.
I'm with Gordy
As usual a whole rumour-mill begins around some mis-information.
When I was active, and had the necessary gear, sadly I never tested E88CC for distortion nor E188CC (7308). But I doubt that there's much wrong with them. I once built a 6SN7 line stage with cathode followers with pentode active loads; this oscillated at about 2.6MHz until I installed some big grid stoppers. Whenever I used E88CC or indeed anything with decent gm I was especially careful - after all if it can happen with a 6SN7...
Hello 316A, how are you doing? Did you ever test E88CC for distortion?
Rgds
7N7
As usual a whole rumour-mill begins around some mis-information.
When I was active, and had the necessary gear, sadly I never tested E88CC for distortion nor E188CC (7308). But I doubt that there's much wrong with them. I once built a 6SN7 line stage with cathode followers with pentode active loads; this oscillated at about 2.6MHz until I installed some big grid stoppers. Whenever I used E88CC or indeed anything with decent gm I was especially careful - after all if it can happen with a 6SN7...
Hello 316A, how are you doing? Did you ever test E88CC for distortion?
Rgds
7N7
6DJ8 distortion
I've measured the 6DJ8 a long time ago, and was surprised by its low distortion. Testing them on my Tek 570 curve tracer shows this also. They have much lower distortion (and a longer lifetime) than the 6BQ7, an earlier non-frame-grid type. This is most likely due to its frame-grid construction. Tektronix changed over to the 6DJ8 en masse in their scopes in 1958, when the 6DJ8 became available, recommending that they replace the 6BQ7s which were heavily used by Tek before then.
Some 6ES8/ECC89s were being remarked as 6DJ8s back in the 1980s, which could explain the weird distortion tests.
I still stand by my claim of "hardness" in the 6DJ8, which is subjective, but I've noticed it in lots of circuits using it. It seems to be worst when the tube is run at low currents. In my recent designs, I've gravitated to the 6N1P, 5687, triode-connected pentodes, and of course, DHTs. But what do I know, I'm only a "consultant".
- John Atwood
I've measured the 6DJ8 a long time ago, and was surprised by its low distortion. Testing them on my Tek 570 curve tracer shows this also. They have much lower distortion (and a longer lifetime) than the 6BQ7, an earlier non-frame-grid type. This is most likely due to its frame-grid construction. Tektronix changed over to the 6DJ8 en masse in their scopes in 1958, when the 6DJ8 became available, recommending that they replace the 6BQ7s which were heavily used by Tek before then.
Some 6ES8/ECC89s were being remarked as 6DJ8s back in the 1980s, which could explain the weird distortion tests.
I still stand by my claim of "hardness" in the 6DJ8, which is subjective, but I've noticed it in lots of circuits using it. It seems to be worst when the tube is run at low currents. In my recent designs, I've gravitated to the 6N1P, 5687, triode-connected pentodes, and of course, DHTs. But what do I know, I'm only a "consultant".
- John Atwood
Re: 6DJ8 distortion
Sadly no. My workbench arsenal just consists of a Tek scope and two DMM's (one of which can be plugged into a laptop, though). Oh and an Avo VCM Mk.IV.
I should really look at getting a some spectral SW for the laptop sometime I guess.
That's been my experience too.
But I should temper that observation by saying that I'm not even a consultant!
Edit: BTW my current phono pre uses 3 6DJ8's in there and I'm not unhappy with it with decent versions in there. (oh wait, I meant "tubes with aurally pleasing differences in tolerances" )
It'd be nice to see if I could do something better one day. We'll see.
(sorry I missed your post earlier)Wavebourn said:
Hi Majestic, nice to see you here!
Actually, do you have an equipment to see the specter?
{...}
Sadly no. My workbench arsenal just consists of a Tek scope and two DMM's (one of which can be plugged into a laptop, though). Oh and an Avo VCM Mk.IV.
I should really look at getting a some spectral SW for the laptop sometime I guess.
JohnAtwood said:
That's been my experience too.
But I should temper that observation by saying that I'm not even a consultant!
Edit: BTW my current phono pre uses 3 6DJ8's in there and I'm not unhappy with it with decent versions in there. (oh wait, I meant "tubes with aurally pleasing differences in tolerances"
)It'd be nice to see if I could do something better one day. We'll see.
BUFFER, so it matters not what tube you use
The tube is being used as a buffer. Buffers add 2 things to tone. Jack and litter box droppings. That's colloquial way of saying a buffer doesn't add anything to the tone.
As for one tube sounding different from the next. in GAIN stages, different tubes DO sound different. The WHY is open to speculation. I've run countless experiments with tubes and solid state and have often been surprised by the results and have often been surprised to discover that often what "everybody knows" just isn't so.
I have used many different dual triodes (preamp tubes), optimized the circuit for each one, and found that yes indeed there are very noticeable sonic differences. Am I alone? Hardly. I used to fall for that "all tubes sound the same" BS. I also used to fall for that NOS is the best nonsense. I bought extremely inexpensive Russian tubes that bested the "holy grail" tubes. Then I tried the 6SN7, 6CG7, and similar dual triodes. They stood head and shoulders above the 12xx7 family. There are differences in power tubes and preamp tubes. Optimize the circuit to get the best sound, using the right impedances, resistors, voltages, etc. experiment.
To reiterate, in this application as a BUFFER, the tube isn't going to add ANYTHING to the tone. You could put a MOSFET in there and you probably wouldn't even know the difference. MOSFETs for the most part make more sense as buffers than tubes do. If you want some of the "effect" of a tube, it needs to be a gain stage. For one thing, tubes compress and some people like a little compression. I'm one who doesn't and I seek to minimize compression by using the more linear tubes.
The tube is being used as a buffer. Buffers add 2 things to tone. Jack and litter box droppings. That's colloquial way of saying a buffer doesn't add anything to the tone.
As for one tube sounding different from the next. in GAIN stages, different tubes DO sound different. The WHY is open to speculation. I've run countless experiments with tubes and solid state and have often been surprised by the results and have often been surprised to discover that often what "everybody knows" just isn't so.
I have used many different dual triodes (preamp tubes), optimized the circuit for each one, and found that yes indeed there are very noticeable sonic differences. Am I alone? Hardly. I used to fall for that "all tubes sound the same" BS. I also used to fall for that NOS is the best nonsense. I bought extremely inexpensive Russian tubes that bested the "holy grail" tubes. Then I tried the 6SN7, 6CG7, and similar dual triodes. They stood head and shoulders above the 12xx7 family. There are differences in power tubes and preamp tubes. Optimize the circuit to get the best sound, using the right impedances, resistors, voltages, etc. experiment.
To reiterate, in this application as a BUFFER, the tube isn't going to add ANYTHING to the tone. You could put a MOSFET in there and you probably wouldn't even know the difference. MOSFETs for the most part make more sense as buffers than tubes do. If you want some of the "effect" of a tube, it needs to be a gain stage. For one thing, tubes compress and some people like a little compression. I'm one who doesn't and I seek to minimize compression by using the more linear tubes.
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