I’ll share what is “tipping’ the scales” for me today. On another site, a commenter was doubting the content of record dust. I recalled this little gem from Shure and thought, “Is my Record Doctor actually getting all of this crap out?” Ultrasonics seem good for diamond dust.
An excerpt from the monograph below:
LIFE TESTS OF DIAMOND STYLI
… One of the chief causes of record and stylus wear is abrasion caused by the material worn off from the stylus itself. These particles worn from the tip become lodged in the record groove and act as an abrasive which accelerates the wear on both the record and the stylus tip. The diamond, being harder than other older stylus materials, like sapphire, does not wear as rapidly and thus does not deposit as much material in the record grooves. This results in less abrasion and consequently less wear. …
DUST AND GRIT
The presence of dust, grit and particles worn from the stylus tip itself not only can damage records and reduce stylus life, but may affect tonal response. An analysis of the "dust" removed from a number of stylus tips, which had been used on dirty records, showed that it consisted of approximately; 12% jagged silica particles, 35% diamond dust, 40% miscellaneous particles, including soot, grit and particles worn from the record groove itself. The remaining 13% consisted of fibers and lint.
https://service.shure.com/s/article/stylus-wear-and-record-wear?language=en_US