Record Damage and Conical and Shibata Styluses

RCA was evidently a subsidiary of JVC:

"RCA was one of the first companies to release quadraphonic product in the United States with it's line of Quadraphonic 8-Track cartridges. (These early "quad-8" tapes can be distinguished from the more common RCA Q8's by their orange colored graphics and solid cardboard album graphic sleeves.) The reason for getting these tapes issued early was to insure that RCA quad product was out into the marketplace while their parent company in Japan (JVC) completed work on perfecting their new CD-4 discrete system for quadraphonic record albums. Early CD-4 LPs released in Japan were suffering from excessive wear and tear. Many of these LPs deteriorated after being played just a few times. This caused JVC to announce at that time that their CD-4 discs should only be played on their specially equipped systems. This problem hastened the development of the "Shibata" stylus, which increased the surface area of the stylus, thus decreasing the pressure on the grooves. With a new improved vinyl and the Shibata stylus, RCA was now ready to introduce the Quadradisc to the American publiv [sic]."

Source: http://www.quadraphonicquad.com/rca_page.htm

There is still some guy in the States who used to work for Audio-Technica making his own CD-4 Shibata cartridge and selling them to people who still maintain a quadrophonic collection.I e-mailed him about their suitabilty for stereo playback and as I thought,he said that would be well within the cartridge's capabilties.

i remember back in the early 70's you had the at15s and the at20s. the at20s was handpicked for it's performance to track not 30,000 hz. but more like 40 or maybe 50 thousand hz.