The Pro-Ject 78rpm Pulley SB is designed to enable modern turntables to efficiently play 78 RPM vinyl records. It is an accessory pulley set that offers functionality by replacing the standard motor pulley on compatible Pro-Ject turntables that originally support speeds of 33 and 45 RPM only. Along with a specially designed square drive belt, the pulley set facilitates an easy switch between 33 RPM, 45 RPM, and 78 RPM playback. When positioned around the larger pulley rung, the turntable operates at 78 RPM, while the smaller pulley rung corresponds to 33 RPM. This modification is particularly appealing to collectors of vintage shellac records, as it allows for the preservation and enjoyment of early recordings without the need for a significant investment in a new turntable. The pulley can be swapped back to restore original capabilities for 33 and 45 RPM playback if needed. It also requires a compatible cartridge to ensure proper playback of 78 RPM records, due to the different groove structure of shellac discs compared to modern vinyl.
