Second-guessing what DD might say, he would probably argue that LP mis-drilling “forces” are oriented at the “correct” (stylus) end of the tonearm and that the cantilever would be intrinsically less stressed than by A/S.Oops, wrong guess! In a discussion of A/S settings, the forces generated by eccentrically drilled LPs are merely a non-sequitar, since no A/S device compensates for them. ;-)
If eccentrically drilled LPs are bothersome, get a TT with an adjustable spindle or ream out the hole and center the LP before play. Problem solved.
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For the record, I never "advocated" for zero A/S. While zero A/S sounds best in my system, I’ve heard other systems where *some* A/S sounded best... Dan_Ed’s for example. FYI, Dan agreed with my take in both cases. Neither of us advocated for anything but making an informed decision.
In using zero A/S I acknowledge the probability of uneven stylus and/or groovewall wear. These effects must result from skating forces if left uncompensated for over time, as PL amply documented.
For me, A/S decreases my enjoyment of music sufficiently that I’m willing to accept those risks. I’m gambling that I’ll be deaf or dead before I hear much deterioration from them. In the meantime, I maximize musical enjoyment today. This pleasant if short-sighted calculus might differ if I were in my twenties. Regrettably, I’m not.
As skating forces are constantly changing, there is no perfect A/S setting and never will be. The optimal setting is therefore an individual matter. So long as the decision is made with understanding and well tuned ears, it will be a good (though imperfect) one. The OCD-prone may find this profoundly unsatisfying, but this particular parameter is not susceptible of perfection.
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To the OP:
- As stated by others, A/S does not effect relative channel output (except perhaps in extreme cases. I’ve never heard it do so myself).
- Adjusting A/S by observing how the stylus behaves on ungrooved vinyl bears little rational relationship to how the stylus will behave in randomly modulated grooves. But so long as you fine tune by LISTENING, that’s as good a starting place as any... I suppose.
- To Raul’s suggestion (clean all contacts) and the suggestion to check channel levels on other sources, I’ll add, try swapping tube pairs (if you have) or L/R signal leads as a diagnostic. It’s easier to fix a problem if you isolate it first.