I'm making a midi clock -> dual tap tempo device (I'm calling it the Twin tap tempo toy, or Tttt). It's based on an Arduino Esplora linked to a dual channel optocoupler / relay.

I'm building it because I have an analogue delay and an an analogue tremolo which each take tap tempo input I want to be able to slave them simultaneously to my DAW (Reaper). I could only find one product (Disaster Area Designs micro.clock) which seems to readily do what I want, and it is hard to find and expensive.

The software side has been pretty easy for me, now I am just troubleshooting the Arduino -> relay connection as currently it is not behaving.

I'll probably sling the code and other docs on Github at some point :)