Re: Re: >20kHz content found in vinyl?
Reply #56 –
... OK imagine carrying a couch; two people required. On level ground, both carry the same weight, going up stairs, the one on the bottom bears more. Pretty simple. If the bearing is in the same plane as the LP, tracking pressure is more constant with warp and bass modulation than if one side is elevated. I'm sure you can work this out (geometry involved), if not try volunteering to help someone move. ...
This is a second order effect. For all sane geometries and amounts of "warp and bass", the tracking force change due to geometry is a very small fraction of the static tracking force. Tracking force change causes cantilever deflection, which causes signal output. The magnitude of this is swamped by the inertia of the arm movement excited by the aforementioned warps and bass modulation.
Another second order effect of not being in the same plane is the velocity change of the stylus relative to the record as the geometry changes. Again, for all sane geometries this is a small effect.
As for gimbal bearings, Triplanar weren't unique. Many manufacturers used very hard materials such as tungsten carbide and zircon to reduce wear. Personally, I developed a preference for unipivots. I found the the dynamic damping produced the best results when faced with the warped and rippled discs common in the 80s.