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tonearms with VTA-towers for true "VTAF"

Hi All,
I think the time has come to look at some more 'advanced' tone-arms that sport VTA towers. ('Old skool' is getting us not much further with this, or?))

During a lot of other, related postings it seems a good subject, I think.

Our experts, all might agree, that:

1) If you want to push the envelope for BEST possible replay, constant VTA 'adaptation' is an unavoidable matter. (nobody said madness :-)

2) I understand this means a TOP cart, inevitably with a 'most modern' type Fine-Line contact stylus, forget elliptical or can one even mention the word, spherical?

Add some TOP cantilever materials like:
- Beryllium (hard to get, as it is a very tricky material to work with i.e. very poisonous in powder form),
- Boron (which mostly has replaced the former),
- Titanium?? (was used by some of the better AT carts),
- Ruby, well some like it I hear,
- Sapphire?? (some one liked that better then Ruby, but VERY little seems about),
- Diamond (see e.g. the DV odd-ball 17D3), etc.

This should make for some VERY detailed and revealing reproduction (even in an MM cart), add to this the most revealing ingredients of a TOP LO-MC.

The end result is, that you can now here some marvellous detail (carved-outness of images, stage-depth -width, and on), B U T ONLY if your VTA is at its VERY closest to what the record was cut to! (Else you find your cart, record, arm, phono-pre, .... system sux :-)

More interesting yet, even the same vinyl brands have not always used the same cutting angles (over time). Anything from just under 20deg. to about 25deg. is what we find!

Next, these high res. styli also have each one their own preferred SRA / VTA angles, i.e. the stylus line-ridge related to the cantilever is a variable too.

Add this all up and you have a problem, particularly if you care for truly top play-back.

If you have a "VTA tower" it only seem to take 15sec. to change to the correct, previously found VTA, you do need to be organised though. If you want some know-how, Doug can tell, see also the discussion under:
"VTA setting for 'parabolic' and 'elliptical' styli"
http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1244713018

There we have mentioned 3 current contenders, I quote: "Graham, VPI, TriPlanar plus a few very costly linear trackers..."

WHAT ABOUT THE: Kuzma 4Point?!

If I wouldn't like e.g.:
- multiple added connections (Graham, 7 in total?)
- wobbly Unipivots (VPI)
- too many fiddly pieces to make up the arm (TriPlanar)
- air bearings, or worse yet 'electronic' arm-feed

If I'd have an issue with these, I've no working solution to the VTAF I'd be looking for.

What say you?

Greetings,
Axel

axelwahl

Showing 5 responses by larryi

larryi
4,151 posts
 
I suppose that the easiest implementation to do repeatable VTA change would be the digital readout approach of the Kuzma. The other useful approach would involve changing VTA by remote control (Air Tangent). The VTA tower on the Triplanar and other on-the-fly implementations are still too much of a bother to me. Also, most VTA adjustment schemes do compromise arm rigidity/grounding of vibration to the turntable base. Those approaches designed to minimize the negative effect of a VTA calibration mechanism, such as the Basis/Vector approach, are not exactly convenient for making constant changes.

Still, changing VTA constantly would be a BIG hassle that would, for me, largely negate the pleasure of listening to records. For me, the biggest concern is with varying thickness of LPs affecting VTA. For that, the only somewhat easy to implement way to mitigate the problem is a long tonearm.

Vinyl listening inherently involves listening past a whole lot of performance compromises. Remarkably, it is still one of the most enjoyable of media. I just choose to ignore the comromise of non-optimum VTA for each record.
larryi
4,151 posts
 
Axel,

Consider the pivot of the arm to be at the center of a circle and the stylus at a point on the circle. Now imagine a change in position of the stylus representing the change in thickness of a record. The movement could be represented by the arc on the circle and the angle between the two positions. Bigger circle (longer arm) means a smaller arc and a smaller angle change, hence less change in VTA as well. Perhaps the change between a 9-inch and 12-inch arm is not that great, but, most of the radial tracking arms are much shorter than 9 inches and I bet record thickness, and the need to adjust for changes in thickness, would be an issue with these types of arms.
larryi
4,151 posts
 
I certainly hope that overhang changes from minute VTA/SRA adjustment is primarily and academic issue and not a practical one. Viewing this purely from an academic/theoretical perspective, an arm, like the ET2 that changes overhang to account for a change in arm height would NOT necessarily be a good thing. If I were trying to maintain a particular VTA/SRA, I would set the overhang to be correct for that particular setting. I would then only change the height of the arm to account for different thickness of the records, while hopefully maintaining the same VTA/SRA. That would mean I would want the arm to go straight up and down and I would NOT want it to alter the overhang to account for a different height of the arm.

Personally, I never bother to change arm height for different thicknesses of records (I own a conventional, 9" arm). But, the resulting change in VTA/SRA from a change in thickness is considerably greater with the much shorter linear tracking arms so it might make sense to adjust the height with such arms for different record thicknesses. In that case, I think it would make more sense to just move the arm straight up and down and NOT attempt to compensate for a change in height. I don't think the ET2 arrangement makes sense from either a theoretical or practical perspective.
larryi
4,151 posts
 
Halcro,

You are correct that this is more a theoretical issue than anything else. That would be the case, too, with regard to the putative advantage of the ET2 moving the arm in an arc to maintain the same effective arm length (although, with the ET2 arm, at less than 9" in length, the amount of variance would be higher than the amount you calculated for a 9" arm).

I certainly hope that vinyl reproduction is more "robust" than what perfectionist insist on for alignment accuracy and optimization for all other parameters. It would be nice to own something like the SMARTractor and an oscilloscope for setting azimuth, etc., but, it would be a real tragedy if these things were necessities.
larryi
4,151 posts
 
I don't really know how audible is incorrect alignment because I have never systematically changed alignment to determine what is audible.

Given how much easier it is to change VTA/SRA, however, I have done that experiment. I too have noticed that small VTA/SRA changes seem to have a pretty significant impact, particularly on high frequency sibilance and edginess. Even a change in height of less than 1mm can change the sound quite a bit even though that translates to a fraction of one degree of change in angle.
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