Stylus force digital scales

lewm

You don’t understand. And you don’t want to understand. So why bother? ... Or simply do the experiment I suggested: Measure or set VTF with the tonearm parallel to the surface of an LP. Then place a couple of spacers under your digital scale ... measure VTF again ... Don’t come back at me until you’ve done this ...

Pardon me, but I’m not obligated to complete your homework assignment as a prerequisite to posting here. I’m sorry if that troubles you.

You seem to enjoy engaging in hair-splitting "thought experiments." You’ll have to accept that such exercises as imagining that I’m a phono stylus don’t interest me.

Two things you either don’t understand, or don’t want to understand:

1. The thickness of an LP has a trivial effect on VTF. Unless you’re playing discs that are an inch thick, the variation in static VTF between the thinnest Dynagroove LP and the thickest MoFi (or whatever) remaster is trivial. And yes, I’ve confirmed this with an accurate digital scale.

2.) Dynamic VTF - which is influenced by such factors as record warp - is nowhere near the absurd plus-or-minus 50 percent range you’ve claimed, provided that the pickup arm and phono cartridge are properly matched and calibrated. In addition, the use of a dynamically balanced pickup arm will greatly reduced the degree of VTF deviation and, as I’ve previously explained, this can easily be confirmed by observing the phono cartridge’s cantilever deflection as it navigates a warp.

Further, to be clear, the actual sonic benefit of using dynamic balance in a pickup arm is hotly debated, with many arguing that a statically balanced arm delivers better performance. Without taking a side on the debate, it’s clear that the enduring debate itself suggests that the consequences of a cartridge’s varying VTF as it navigates an LP is nowhere near as critical as you would seem to suggest - again, provided the system has been properly matched and calibrated from the outset.

Some users of dynamically balanced pickup arms such as the SME V apply VTF by using equal amounts of static and dynamic force. You might want to try it sometime, if that’s an option for you.

cleeds,
Let's agree to disagree, once you have acknowledged the following:
(1) Our disagreement is NOT about the degree of difference in VTF caused by a warp or whatever.  I have written twice already that I agree the difference is "small" (if we're talking about LP thicknesses).  I thought we were arguing over your statement in response to someone else, to the effect that VTF would not change AT ALL when the stylus traverses a warp, because (you said) gravity is a constant, etc.  I of course agree that gravity is a constant, but you failed to take into account that raising the tonearm up above the horizontal, as happens when playing a warp, does change VTF, because it changes the geometry and introduces a force vector that is not directed downward, perpendicular to the LP surface.  That small force vector subtracts from the effect of gravity to pull the cartridge down on the LP, reducing the effective VTF.  And talk to Einstein or any other theoretical physicist, if you cannot abide thought experiments.  Based on the limits you want to set on logical arguments, we would still believe in a flat earth.

I notice now that you have changed your tune; you now say that the "thickness of an LP" has a "trivial" effect on VTF.  At least you agree that a thick vs thin LP or a warp would have SOME effect on VTF.  And I am telling you why it would.

(2) The bit about Dynamic VTF. You are confusing me with someone else (whom I respect) who commented that tonearms with dynamic VTF would be less subject to variation in VTF on warped LPs.  In fact, I think you're misquoting him, but go argue with that guy.

@lewm as I said in my last post my experience is that even scales with non magnetic pans suffer from magnetic interactions. I own several scales with such pans and all read differently than my all plastic options (cartridge man and rega) - and all read exactly the same with reference weights (which are not magnetic)

folkfreak, That's very interesting and a bit disconcerting.  Steel can contain some low concentration of iron, so that may be the problem. I will check the weigh pan of my digital scale with an actual magnet, to see if the magnet "likes" the weigh pan at all.  FWIW, the weigh pan on my digital scale is white-ish in color and looks like it may be ceramic, not metal at all, which I hope is the case.