"Adjust for proper timing between fundamental and harmonics."
Since it came from Frank Schroeder, who is widely regarded as a guru in all matters vinyl, this simple statement sounds brilliant and true. Now, will someone please tell me how "timing" is affected by SRA? I thought I knew that timing was the job of the turntable. Perhaps what is meant is that when proper tonal balance is achieved (by optimal adjustment of SRA/VTA) then harmonics are more naturally portrayed, which may give one a sense of better time-dependent relationships. (I don't really even like this, my own, explanation.) But when a guru speaks, the faithful must struggle to understand.
My difficulty understanding Mr. Schroeder's statement (which you all seem to accept as gospel) reminds me of a well worn anecdote about an all-knowing Buddhist monk who lives high in the Himalayas. A group of his acolytes struggle for months through deprivation and hardship, climbing to reach his lair, whereupon they ask him, "Oh great one, please tell us, what is the meaning of life?" His response: "A wet bird never flies at night." |
Peter et al, If you hear an effect of VTA on timing, I don't doubt it. I just wonder why that would be so. I certainly believe that VTA adjustment makes a difference, and I do pay attention to it in a non-anal way. However, I never thought about it in the way stated or inferred by Frank Schroeder. If there is substance to it, it's interesting to me. |
None of you explained the mechanism, only why it is a good thing. I agree it is a good thing. After thinking about it last night (what I do in the dark before sleep), I decided maybe it has to do with how music is encoded in the groove vis how the stylus contacts the groove and is thus able to translate physical undulations in the groove into an audio signal. The relation between the stylus geometry and those undulations might be the critical factor. I could imagine how that might effect what some would call "timing". But I don't think it's really timing by the formal definition of same.
Also, I commend you (plural) and anyone else who can confidently distinguish first order harmonic tones from the fundamental. As a (part-time amateur) singer, I can tell you that is no easy thing even in a live venue. The brain doesn't really care a lot about that first octave of tonal difference. (Why sometimes if my pianist starts out an octave too high, I will go right along with him, until I realize that the high notes are going to be out of my vocal range.) |
Yes, but "timing" per se is the job of the turntable. The turntable provides the "X-axis" for the music, which is time. Who could argue that correct time is not important? Not me. |
Dear Raul, Perhaps I am mistaken but was there not a time when you expressed the opinion that small errors in overhang do not make much audible difference, may not even be "important"? I thought that was your position vis a vis that of Dertonearm et al, who was arguing the opposite. If my memory is accurate, what made you change your mind by 180 degrees? |
On the subject of stylus overhang:
If the pivot to spindle distance is set exactly right, meaning +/-0.3mm of the recommended, because that is the best anyone can do, then it seems to me that small errors in overhang (say +/-1.0mm, but I would have to do the geometry before settling on that margin) can be tolerated.
Reason: None of the accepted tonearm geometries achieve more than two points on the arc of the stylus tip where there is tangency. The various algorithms differ only in the locations of these two points along the LP surface (and they also do differ in the amounts of tracking error at other points along the way, but I am not debating that here). A small error in overhang, assuming P2S is correct, will only move those two points of tangency by small distances in or out on the radius of the LP. So long as those two points remain on the playing surface, what is lost? |
John, What do you think is meant by the first sentence in that article you referenced?:
"Adjusting the cartridge for optimum SRA may alter the VTA away from optimum. Or vice versa."
I usually think of VTA as a useful surrogate for SRA, but I guess that a separate function of VTA, apart from its direct effect on SRA, would be to alter the angular relationships between magnets and coils, but that is a major function of VTF. The cantilever/magnets/coils are fixed in space except for the effect of VTF to re-position the cantilever, if too much or too little VTF is applied. Which takes me back to my question; what are they talking about? |
John, Thanks for the treatise. I agree with your definitions of the terms, but I cannot see the point of your statement:
"Now while the stylus might be set at 92 degrees, the cantilever may not be at the same angle as the the cutter."
The cartridge is a transducer whose optimal function depends upon a fixed spatial relationship between the magnets and coils, as one or the other vibrates. Once the LP is cut, why should the cantilever give a damn about the cutter angle? The stylus "cares" about that in terms of SRA. So I would think that you set VTA so as to obtain proper or optimal SRA, first of all to assure proper energy transfer between groove and stylus, and then it is VTF that mainly assures the proper spatial relations between the transducing parts of the cartridge. VTA is just a convenient surrogate for SRA. Probably this has become a discussion about semantics. |
I think the Arche headshell (from Dertonearm, aka designer of the Axiom tonearm) allows for changing VTA at the headshell. I think this would fit Jonathan's requirement for changing VTA without changing the height of the vertical bearing, so as not to alter VTF. And of course the Arche could be used with most pivoted tonearms. I have no affiliation of any kind; nor do I own an Arche headshell. I don't find it to be a terrible bother to re-adjust VTF. What I usually do is get the VTF in the right ballpark, then settle on VTA, then finalize VTF, and Bob's your uncle. There is such a thing as "good enough". |
Jonathan, Thank you for your response. I too have never beheld an Arche headshell in person, but from what I've read about it on other threads, you are correct. So, my concept of how that works is to rock the cartridge either forward (and downward from the horizontal plane with respect to the top surface of the cartridge body) or backward (and upward from the horizontal). True, this would very slightly alter overhang and effective length, in either case, because the stylus tip must move in an arc along with the cartridge. But since very tiny movements of this kind have a drastic effect on VTA and SRA, perhaps the effect on those other two parameters would be minimal, i.e., acceptable. I guess there's no free lunch. |
I was trying to fix my post when I accidentally posted it. I obviously was referring to the front end of the cartridge body when I wrote that a "forward" tilt would move the cartridge body "downward". The rear end would move upward. |
Smoffat, I think your sequence would work, except then the truly precise audiophile has to start over back at "VTF". In other words...
VTF
Overhang/Zenith
VTA/SRA
Antiskating
Azimuth
Damping
VTF
Overhang/Zenith
VTA/SRA
Antiskating
Azimuth
Damping
Etc. |
