Tape Delay Helper/Interface Module

MixTape is our first fully analog module! It is a helper/interface module to connect nearly any 3 head cassette or reel to reel deck to Eurorack and features audio grade OPA1679 op-amps.

The 3 knobs control the input level to the tape, the tape feedback, and dry/wet. There are  4 jacks. The top row is for Eurorack input and output while the bottom is tape return and send. Tape return and send are line level.

The module includes a non-resonant 2-pole low-pass filter with a cutoff of ~16kHz. This is meant to help avoid bias bleed from making its way into the audio path for tape machines that have a bad bias defeat circuit. While it doesn't fully eliminate tape screech in those scenarios, it seems to help considerably.

This is a similar setup to how one might connect a tape deck to a mixer for tape delay, only here it's in a compact 4HP module!