Post by Deleted on Sept 18, 2021 21:20:22 GMT
My SUPATRAC Sideways Uni-Pivot Arm (SUPA) has been discussed without great clarity in an amplification thread so I decided to explain the invention briefly here.
The novel SUPA bearing is being patented internationally. It solves the two main problems with a uni-pivot: roll and rub.
Roll occurs because traditional uni-pivots are free to rotate to a limited extent in the axis of the arm. Uni-pivot users are familiar with the arm's tendency to wobble laterally during cuing. This is an unwanted freedom, and almost certainly leads to instability in response to widely unbalanced stereo signals.
Rub is a less discussed problem, hypothetical but probably also real. The drag from the stylus varies significantly during music, and all vertical pivot/cup geometries are likely to develop the freedom to slip back and forth by tiny increments after many hours of use. Any degree of movement in the time axis is destructive to the perfect accuracy of the signal.
The sideways uni-pivot arm orients the pivot pointing away from the stylus, sideways, so that drag forces do not generate rub. The suspension trapeze obstructs roll by forming a fixed vertical axis comprising the suspender ground point and the uni-pivot point.
Here is a video of an early prototype of the patented bearing design which illustrates how a single point bearing can successfully be oriented to oppose drag, but introduce no friction to yaw and pitch movements:
link
I hope that it will be apparent to some that with only one point of solid contact, and freedom to move only in the required axes, this bearing approaches an ideal pivot bearing more closely than previous designs.
I suggest that the performance of the SUPATRAC Blackbird is not so much a myth of marketing, but rather a direct result of applying the laws of physics in a novel bearing mechanism which more accurately solves the problem of tonearm bearing rigidity than traditional solutions.
The novel SUPA bearing is being patented internationally. It solves the two main problems with a uni-pivot: roll and rub.
Roll occurs because traditional uni-pivots are free to rotate to a limited extent in the axis of the arm. Uni-pivot users are familiar with the arm's tendency to wobble laterally during cuing. This is an unwanted freedom, and almost certainly leads to instability in response to widely unbalanced stereo signals.
Rub is a less discussed problem, hypothetical but probably also real. The drag from the stylus varies significantly during music, and all vertical pivot/cup geometries are likely to develop the freedom to slip back and forth by tiny increments after many hours of use. Any degree of movement in the time axis is destructive to the perfect accuracy of the signal.
The sideways uni-pivot arm orients the pivot pointing away from the stylus, sideways, so that drag forces do not generate rub. The suspension trapeze obstructs roll by forming a fixed vertical axis comprising the suspender ground point and the uni-pivot point.
Here is a video of an early prototype of the patented bearing design which illustrates how a single point bearing can successfully be oriented to oppose drag, but introduce no friction to yaw and pitch movements:
link
I hope that it will be apparent to some that with only one point of solid contact, and freedom to move only in the required axes, this bearing approaches an ideal pivot bearing more closely than previous designs.
I suggest that the performance of the SUPATRAC Blackbird is not so much a myth of marketing, but rather a direct result of applying the laws of physics in a novel bearing mechanism which more accurately solves the problem of tonearm bearing rigidity than traditional solutions.
