Highest amplitude 300Hz track
Detail of highest amplitude 300Hz lateral cut track.


The makers of this test record could have allowed themselves a little more groove pitch in this last, highest amplitude track, for the land between grooves disappears here and there as the grooves run into one another.
Despite this, a correctly tracking stylus will not skip grooves, as the area of contact with the groove wall is still sufficiently below the record surface for tracking to be unaffected.

The picture has been taken through one eyepiece of a stereo microscope, and since it views the record surface obliquely, a narrow zone of focus runs from top to bottom in the middle of the picture.

The picture below shows a Shure V15 MkIII stylus tracking a record. Work is proceeding to devise optics and lighting to demonstrate changes to the SRA (stylus rake angle) and/or VTA (vertical tracking angle) caused by altering the height of the pickup arm, changes to tracking force etc., and to address some of the confusion which surrounds these terms.

Shure V15 III tracking groove.
Shure V15 Mk.III cartridge tracking a record.



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