The M93, Prime Time, had 128 ms of memory standard which could be upgraded to 256 ms and passed frequencies up to 12kHz.

The M95, Prime Time II, had 1.92 seconds of delay, with options for 3.84 and 7.68 Seconds and passed frequencies up to 16 kHz.

The M97, Super Prime Time came with 640ms of delay with an option to 1.28 S. It passed frequencies up to 20kHz and was programmable.