Michael Fremer

Ideally, LPs should be played with the pickup stylus remaining tangential (ie, at a 90° angle) to the groove—just as the lacquer from which the LP was ultimately stamped was cut in the first place. Over the years, many attempts have been made to accomplish this. Back in 1877, Thomas A. Edison's original machines tangentially tracked his cylinders, but Emil Berliner's invention of the flat disc put an end to cylinders altogether. In the 1950s, a number of companies marketed so-called "tangential" trackers that used dual arms, based on conventional pivoting arrangements, to change the angle at which the headshell was mounted as it moved across the LP side. In 1963, Marantz introduced the SLT-12, which used a plastic pantograph to move the stylus across the record surface. Garrard's Zero 100 pivoting arm controlled its independently pivoting headshell with a bar that extended from the main bearing of the tonearm.