Stylus Force Guages - why extreme accuracy?

Sdcampbell,

Me three. Both VTF and VTA/SRA can be fine tuned by listening, assuming your rig and ears are interested of course. :-)

Lloyd Walker's well-written guidelines are worth reading: http://www.walkeraudio.com/fine_tuning_your_turntable.htm

FWIW, we also adjust antiskate, azimuth, impedance and even drive belt tension by ear. VTF changes are just as audible as changes to these other parameters.

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Seasoned,
Metralla's explanation is also why I have a .01g scale.

When the weather changes and/or I swap cartridges I want to dial in a baseline VTF quickly. On my tonearm I need to set VTF within .05g or so before I can use my fine VTF adjuster.

For me a .1g scale would be too coarse. If it read (e.g.) 2.0g, all I'd know is that I'm "somewhere" between 1.95g and 2.05g. With many cartridges a range that wide is so vast you might as well not use a scale at all. My main cartridge has a sweet zone for VTF that is .02g wide at most. Setting it up without a good scale could take hours, instead of minutes.

We've talked about this a number of times, and it appears that many seasoned audiophiles enjoy having highly accurate gauge in order to re-set the cartridge to a previously determined optimal tracking force. Reasons for this range from swapping cartridges and/or armtubes periodically to making VTA changes in arms that can have their tracking force thrown out inadvertantly in the handling process.

Then, there are folks like me (and possibly you) who don't have these needs and rely on fine tuning by ear with a gauge like the Shure just to get us in the ball park to start that process. I follow Lloyd Walker's turntable fine tuning advice for iterative adjustments of VTA and VTF to do my fine tuning. Then I adjust VTA for each different record weight, leaving VTF fixed. (The small VTA adjustments between 150, 180 and 200 gram LPs are very noticeable and absolutely necessary for my ear and my system, but they don't interact enough with VTF to warrant changing the VTF for each of these subsequent VTA teakings.)

Sdcambell, my experience has been that for setting up a tonearm/cartridge an iterative dialing process of changing VTF, then changing VTA, then changing VTF, is needed because of the interaction (just as Lloyd recommends). Thereafter, as noted above, I don't bother changing VTF when I adjust VTA between LPs because the difference truly is miniscule to unnoticeable at that point.
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Anyone remember their college physics? How much of an error will be caused by having the stylus 1/2 inch higher or lower than the record surface? I doubt it is much, but haven't cracked my textbooks to do the calculation. Anybody?

Peter_s,

Having one's stylus 1/2 inch higher or lower than the record surface would have a HUGE impact on sonics, namely, there wouldn't be any! ;-)

To respond seriously, we've discussed various explanations for the audibility of SRA/VTA adjustment several times over the years. An archive search will turn up several endless (and occasionally acrimonious) threads. There's no point going through all that again.

To summarize, no explanation has yet been posited that explains what people hear while satisfying the mathematically skeptical. Conclusion: the state of scientific knowledge still trails our experience of reality in this area.

If you're serious about researching this question, I'd recommend beginning with some archive searches here and at VA. You'll find enough material to keep you reading for weeks. I particularly recommend one article in the VA FAQ's, Jon Risch's "VTA once and for all". It comes closest to explaining what I hear, yet skeptics have expressed doubt that the degree of changes involved could be audible. They would prefer an alternate theory, but no more satisfactory one has been found AFAIK.

One long and inconclusive thread here was blissfully terminated by a practical post from Tbg. He wrote, "If you hear it adjust. If you don't, don't." Not a productive attitude for the scientific investigator, but a very productive one for the music lover/audiophile.

Nice reply, Doug. I think you captured it well.
Regards,