Anyone here familiar with the old synth drums from early 80s pop and disco era? i want to build a circuit to reproduce that sound, i have a circuit for the VCO but i don't know how to get the voltage to control it once i trigger the input, i need to be able to have a voltage that starts off at 5V then slowly falls to zero after the VCO is triggered to get that falling beooow beooow sound as in the synth drums in the song love dont live here anymore by rose royce etc.

I simply have no idea where to start.

 

I found what i needed.