Is extremely accurate "VTA" adjustment necessary?

Platter: a 70lb lead platter machined flat to within "one-half of one-ten-thousandths of inch" across the entire platter surface.

You won't get *that* with a wooden platter!!!

Dear Rene: I agree with you ( your second answer ) and Twl
points of view. here it is one of my answers in the past on this subject:

05-24-04: Rauliruegas
Dear Samir: Here it is another way to adjust VTA/SRA:
invert the polarity in one channel, put a mono record, set the preamp in mono and adjust the VTA/SRA where you hear least sound.
The VTA/SRA is a critical parameter, but don't be madness and obsessive with it.You, like me, want to enjoy music instead of adjusting equipement, so always we have to take a compromise position. I recomended that you use an average thickness record or 3 to 4 different thickneses/labels of records and finding the best compromise. Then : turn on your audio system and enjoy listening to the music.
BTW and only for information: The industry standard for cutting head VTA is 20 degrees, each cartridge is designed to function around this angle when the tonearm is parallel to the record, so you have to start with your tonearm parallel to your records, this position is very very close to the " ideal ".
There are many issues in the VTA/SRA, but what you want is to know how adjust it and I think that now you already knew it.
Best wishes and always enjoy the music.
Raul.
Rauliruegas (Answers)".

Now, the only way to get the perfect VTA/SRA on a record is using a scientific tool like the Spectra Lab. We can't to have the perfect VTA/SRA through our ears, but through our ears is the easiest way.
Now, I don't want to go on with the same answers that other people ( including the article reviewer ) already speaks about. What I can tell you is that with your cartridge it will be very dificult to hear minute changes in the VTA/SRA.
Rene, you told us that you have 10 years of experience in analog: Doug has only 13 months on analog, but as you can see he feels like an " expert ". Hi is an inexpert people (likes to be in any single thread repeating what other people say. Don't do any own contribution )on analog and this is reflected with his wrong attitude against the article on VTA/SRA and that in your fouth answer you put all things very clear. Be carefully with this Doug.
Regards and enjoy the music.
Raul.

Raul,
I have read many of Doug Deacon's posts over many months (both here and on Audio Asylum) and I consistently find them independent, thoughtful, based solidly in his own experience and listening tests, and quite well reasoned. I think you have very inappropriately "slammed" him in your comments. You and Doug have disagreed a number of times; that is no reason to make this personal attack which I find both unwarranted and offensive.
.

Thank you all for your responses.

4yanx - Thanks for your response. Of course I could just go ahead and get the vta adjuster anyway. I just wanted to have some more rational reasons before handing out $200 for vta. Since everybody here seems to agree that differences in record thickness need vta adjustment possibility, it would be difficult to find a better solution for the price.

Rushton - Thank you very much for all the details about the Walker Proscenium turntable. Out of own experiences I know that any tolerance below a thousands of inch takes a lot of effort and care and is certainly not cheap to produce. I very much doubt that my Michell turntable is even close in tolerances. I never had a chance to see the Walker table live, I would be very interested to see the solution they found for a rigid vta adjuster. Another number I am really interested in is the thickness variation of a record. I probably should call Classic records to find out what the tolerances are in the production of their current Quiex LP's. I'll keep you updated if I find out more.

Psychic - For now I was more thinking along the lines of an acrylic platter, which is probably closer in tolerances. I doubt I will be able to afford a Teres with wood platter anytime soon.

Raul - Thanks for your support. So far I haven't really worried too much about vta. I do have a Rega arm which is a pain to adjust on any table. The Michell vta adjuster (or the incognito for that matter) is fine but I suspect it is going to have exactly the mechanical problems mentioned in the article. The vta I found with the adjuster was actually close (less than +-0.5mm) to the 2mm Rega spacer, which I thought sounded actually slightly better when I changed it. I would certainly appreciate a more solid vta solution, however I doubt I will play with vta adjustment too much. I usually adjust everything in my system so that I really like the way it sounds and then usually just leave it alone for a while and just enjoy the music. As with respect to my experience in analog: I only have had three different turntables and four cartridges, which certainly does not make me an expert. Also I never really had a high-end setup. Also I do think Doug does give good and thoughtful answers. I have posted several times in the same thread as Doug and I always thought he was quite spot on. Also on Personal turntable/cartridge evolution he did mention that he had a various tables since 1967. (If you get a chance it would be great if you would post your history there as well.) Otherwise, I agree: Enjoy the music.

Also one more comment: I just think the science perspective on audio has always led to heated debates, and vta adjustment is right on the line in that respect. I would prefer though if we can keep personal attacks aside.

All the best to everyone,

Rene

Rene,
I reread the article and understand that a key aspect of it is your question, "Is it really VTA/SRA changes that we're hearing or is it something else?" Apologies if I seemed to be dismissing it. This article has been used or mis-used both here and elsewhere by those with non-scientific motives. I suppose I was responding to those rather than to the article itself.

"Why don't we hear the variation in VTA as the LP rotates, since this variation is much bigger than changing the arm height by .005'"

That is a good question. Finding answers could indeed lead to improvements in music reproduction on vinyl. Even if the TT is perfect, many records are not. Neither Rushton nor I have vacuum hold-down, though I do use a periphery clamp. Even with two clamps however, some records just aren't flat. This makes the question very interesting. Wish I could suggest a satisfactory answer, but at the moment I can't.

The theory of changing resonant behavior doesn't seem completely satisfactory when the same differences are being reported across multiple, high quality rigs. I wonder if that theory came from the well-observed behavior of Rega style arms, which DO change audibly every time you adjust the arm locking nut?

It is *possible* to carelessly adjust arm height on a TriPlanar in such a way that its sonic character *might* be effected. The VTA tower raises/lowers the arm on a large diameter threaded rod. The good aspects of the design include a long thread contact area, to prevent wobbling about the vertical axis, and a set screw that pulls the entire mechanism tight against the outer housing. Lots of contact area, not just one screw point. Still, as with any mechanical device, there is some play in the mechanism. For example, one can approach any given arm height setting from either above or below. If one approaches a particular setting from above, the slack in the threads may not all be taken up. For this reason, I always adjust by bringing the mechanism *up* to a setting before locking the set screw. I can actually feel the weight of the arm moving up, so gravity is helping defeat any looseness in the threads. I also give the arm support a little nudge back and forth while turning the set screw to lock the setting in. This assures that the set screw mechanism is solidly seated. When carefully adjusted like this, a TriPlanar is quite rigid. Once it's locked down, any attempt to move the arm mount in any direction simply moves my 60 lb. turntable, without affecting the arm mount itself as far as one can tell by feel. No, I'm not going to pick up the table by the tonearm to test that!

I suppose it's possible that the mechanism's resonant behavior could change when I raise or lower the arm a few thousandths of a mm, but the kind of musical changes I described above don't seem to be consistent with that model, at least to me. They seem more consistent with the idea that the timing of when the playback stylus hits each individual groove modulation must match the timing as they were originally cut. SRA in other words. :-( Back to where we started.

Thank you Rushton and Restock for your supportive comments, and for even taking the time to unearth examples of why these attacks are without basis. I guess that's what honest men do. This little vendetta has appeared on multiple threads in the last couple of weeks, for whatever reason. I have chosen not to respond so as not to contribute to any deterioration in our normally enjoyable atmosphere. I will continue that policy. We all disagree from time to time, but that's no reason to poison the room. One wonders why the moderators haven't stepped in.

One point Raul made does need elaboration. "The industry standard for cutting head VTA is 20 degrees..." That may be true today, but manufacturing variances happen at all times and millions of records were cut before the standard existed. Old Deccas/Londons, for example, were cut at lower angles than more modern ones. If one only listens to recent releases then Raul's point would be more valid.

Golly, I sure hope Rushton's platter is flatter than mine. He paid enough for it. Why don'cha know, last Summer my li'l Teres actually absorbed 158 pounds of airborne moisture (Raul measured it for me). Why it blowed up so much it looked like Jabba the Hut. The spindle turned into an "inny"!