INNER GROOVE DISTORTION

Forty years ago at WSU my stereo skills were known so far and wide I had strangers calling me up for advice. Usually a few questions and boom problem solved. One time though I was thirsty, I can fix it, for a beer. When I already knew the fix. And so, walk in, where's my beer? Thanks! Quaff. Flick. Wow sounds great you're amazing here's another beer! (The half-life of a beer at WSU back then was in the milliseconds.)

So of course these things can be diagnosed and fixed at a distance. Its the beer delivery where things get a bit tricky.

But as for the "problem" the L channel information is on the left, R is right. I'm talking the groove as seen facing the turntable. So if the L is breaking up its bouncing off the inner side from too much anti-skating, so dial it back. If the R is breaking up its the other way around. And if BOTH are distorting then its nothing to do with skating, anti or otherwise, its the cartridge body is rotated too much one way or the other on the vertical axis, otherwise known as zenith. In that case go back to your Baerwald and fix the alignment problem.

Now, please PM me for delivery instructions. And make it a porter.

Oh wait, what’s this?

I don’t use anti-skating, just twisting the cable going to the junction box.

Actually knew that was there but only just now decided to use it. Classic example of why however good VPI are I’d never recommend one for the arm. Twisted wires. Sheesh!

So what happens is as the arm swings closer to the center the torque on the wire increases and this means a VPI arm will always have more anti-skate at the inside than at the outside. Its never right and anti-skate usually isn’t all that particular anyway (watch Lederman, explains beautifully why it is at best an average or trade-off) but still, twisted wires, I mean come on!

So odds are your twisted wires are twisted okay for the outside but too much for the inside. If this is the case then it will be the inside or Left channel that’s distorting the most.

Leavenworth Bulls Tooth. The porter, I mean.

It appears that the compliance of your cartridge is either 22 or 28 um/nM, depending on which version of The Voice it is. Either way, those numbers are high enough that if anti-skating is significantly misadjusted you should be able to see visible deflection of the cantilever to one side or the other when viewing the cartridge head-on while it is in the groove of a rotating record, relative to its position (nominally straight ahead) when the stylus is lifted off of the record.

I suggest that you take a look at that when the stylus is near the beginning, the middle, and the end of a rotating record, preferably during musical passages having relatively low volume. Too little anti-skating force will result in cantilever deflection to the right (toward the outside of the record); too much anti-skating force will result in deflection to the left (toward the center of the record).

Hopefully you will then be able to find an amount of twist that results in minimal or no deflection at all positions on the record.

Regards,
-- Al

I have toyed with twisting the tone arm wire, in my opinion it messes with azimuth which changes as it moves across the record. Much better to have nice even loop in the wire.

I'm with millercarbon.  If the distortion is "global" (i.e., in both channels), then I doubt it's due to a lack of anti-skate per se.  Also, if you had a pronounced lack or excess of anti-skating force, you would hear the effect at the outer grooves as well as at the inner grooves. As millercarbon mentioned, too little anti-skate affects the R channel predominantly, and you would hear R channel distortion from the first second the needle hits the LP.  Too much anti-skate will do the same in the L channel.  My guess is that the movement of the tonearm is impeded by something (wiring, maybe?), as the tonearm travels toward the spindle.  That said, I do agree with others that the lack of any provision for anti-skate typical of older VPI tonearms is egregious. Check also to see whether the cue-ing device is fouling the arm wand, as the arm pivots toward the spindle.  Likewise for the counter-wt.