Discrete ADSR 2

Courtesy/Thanks to: Rene Shmitz

Description: The second image shows a much simpler ADSR which uses a 555 timer IC to do nearly all what is needed. It is preceeded by a transistor circuit which buffers the input and generates a short pulse which is needed to trigger the timer. This is the circuit that I now use, since it has more musical properties. Unlike the first circuit the attack portion of the ADSR goes immideately to decay when the gate goes low. In the first circuit the attack (once triggered) goes until the 10V threshold is reached, regardless of gate going low. This circuit was modified from a circuit from Hal Chamberlins book Musical applications of microprocessors.