Down With the Masses!
One of the major goals of any cartridge designer is to keep the effective moving mass of the unit as low as possible. In premium cartridges the smallest diamond styli are used, cantilevers are made as light as possible, and magnet size is reduced to the minimum.
Lighter and Smarter
But making parts smaller and lighter is just one approach to the problem. Careful and creative location of each moving cartridge element can make the mass seem even lower. For instance, the geometry of our two Vector-Aligned magnets reduces the effective magnet mass seen by each groove wall to barely more than half the total magnet mass. With single-magnet designs each groove wall must move the total magnet mass, thus increasing the load on the record and stylus.
One-sided Design
But we go an important step further by locating all of the moving parts of our stereo cartridges on the same side of the pivot point. With most other designs the stylus and cantilever are on one side of the pivot (or fulcrum) and the magnet is on the other.
This traditional, longer construction is inherently more massive.
The Payoff
Any reduction in the effective moving mass of a phono cartridge will improve record reproduction. First, it reduces the stress on the groove walls, extending record and stylus life. It makes it possible for the stylus to accelerate more quickly in response to very high frequency signals. High frequency tracking is also enhanced by low effective moving mass. This improves frequency response and lowers distortion, especially during musical climaxes which often combine high signal levels with very complex wave shapes.
Across the Board
This basic concept of geometric mass reduction is not limited to our most expensive models. It is inherent in every Audio-Technica Vector-Aligned cartridge. And its benefits have made even our least expensive models unusual values, while enhancing the capability of our most sophisticated stereo cartridges.
Good listening, Jon R. Kelly. President Audio-Technica U.S. Inc.
1221 Commerce Dr., Stow, OH 44224
audio-technica.
The World's Favorite Phono Cartridge
(Adapted from Audio magazine, Jan. 1985)
Also see:
audio-talk from audio-technica -- Number 9 in a Series (advertisement, Nov. 1984)
audio-talk from audio-technica -- Number 7 in a Series (Sept. 1984)
audio-talk from audio-technica -- Number 4 in a Series (June 1984)
Audio-Technica AT15Sa cartridge (Feb. 1977)
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