Quote Originally Posted by daveobieone
Whoa...I wish there was some way to see some of those photos!

I've always been interested in the amout of deformation of the groove walls by the stylus. Especially with different shapes, VTF, etc.

Does anyone have an opinion about which is more destructive to the groove wall...
Tracking distortion, or tracking heavier?

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I recall back in the early '70s I think it was Audio magazine had an article about groove wear, downward tracking force and it's effects, complete with scanning electron microscope pictures. Don't recall if they did any testing with other than with an elliptical stylus, might have been earlier than the newer shapes like Shibata and Stereohedron, but the value of 1.2 grams stuck with me. 1.2 grams and higher there was some evidence of permanent groove wall distortion, 1.1 grams and lower, anything seen within the groove walls "recovered" for the most part. And yes, not enough tracking force caused damage too, from the stylus bouncing around between groove walls. Wish I could find a reprint of that article.