KrisM
18
yeah well. It’s DAC is a lot cleaner/more moden unfortunately. The FB-01 has a 16-bit DAC vs 18 (12+6) in the PreenFM, and iirc it was only technically 16 bit; it was fed by a 10-bit serial connection. I’d have to look up the specific chip to be certain.
I’m actually keen to try my hand at making a modular digital FM out of my Patchblocks when they arrive. 10-bit 20kHz, yum 
Also, I feel dumb for not saying the OP-1 lol. One of it’s synth engines is called FM
Though it will still be output through a 24/96 DAC