Klavis CalTrans

The CalTrans corrects tracking very well (I got a 1-2 cents error in 6 octaves for my Pittsburg Taiga), increases the tuning range for modules that don't have a wide range by default, and corrects inaccurate CV outputs of controllers (like Keystep Pro) by quantizing them.

The only problem is that its calibration input seems to be sensitive to noise, so the signal may need to be filtered to calibrate.

It's not obvious from the documentation, you expect to just plug in the cable and calibrate anything, but that's not the case with this module, I even thought my module didn't work.

Also, the interface of the module is not obvious. If you don't use this module all the time, you have to remember from the documentation what these blinking lights mean.