The R-606 is a vintage drum kit in a 28-pin DIP.
It features 7 polyphonic drum sounds and 6 analog level inputs.
1 global accent input.
Sounds are virtual analog modelled for a true vintage sound.
I have used Spice for modelling so you could call it “Circuit Modelling”
The chip can be ordered for $30 including international shipping.
More at http://www.dspsynth.eu including application documents.