I have a pair of M400s that have the original motor drive boards. They are in storage, but I would like to start restoring them now. One thing I would like to do is replace the motor drive board with something that does not sag, i.e. will support a couple of fistful of notes without slowing down. Does anyone have any data on the correct voltage range and the typical current draws for different numbers of simultaneous notes? There are a number of DC motor controllers on the market for industrial applications, and I'm hoping to find one to match up with the Tron's needs.
best,
Richard
Troy, VA