Polyphony
Polyphony is needed to play multiple notes which don't cut each other off and act as true independent voices each with their own controllable parameters. Polyphony is the ability to play multiple independent voices simultaneously, and requires enough oscillators, envelopes, filters, VCAs and other modules to build an entire voice block for each simultaneous note required. this is expensive and also requires a polyphonic sequencer source to provide multiple independent pitch, gate and other cv's.