Ortofon 2M 782M 78 features: An improved engine, which provides a high level of sonic accuracy Spherical diamond that is perfect for playback of 78 rpm shellac records, which require a larger stylus profile 2M 78 uses a strapped output to deliver the same output signal from both sets of pole pins. This effectively eliminates the need for mono specific equipment, making it possible to enjoy true mono reproduction on any stereo playback system.