Mono and Poly

One voice at a time or many at once; the choice changes both playing and arranging.

Related

PortamentoMinimoogPolyphonic synthesisModern

The question

Why does a new key cut off the previous note on some synths, while others hold six? Mono and poly are not just specifications; they decide how a line is written.

How it works

A mono synth has one voice, so a new key takes over the previous note, and the player chooses whether it glides. A poly synth has several voices; a keypress claims a free one, and when none remain it steals the oldest or quietest. Voice count sets how many notes can sound together, and whether long releases are cut short. Octave-divider polyphony generates several notes from a few oscillators, but the same note name cannot repeat.

Settings and what you hear

Mono suits bass and lead lines, written as a single thread; the glide between notes decides whether it sings or jumps. Poly suits chords and pads, and more voices pile up more low end. Voice stealing appears when releases are long, and the tail vanishes. In mono legato the envelope is not retriggered, so the attack appears once.

What to listen for

Hear a single-channel lead and notice that only one note sounds at any moment, with no chord at the changes. Then hear an organ chord and count the notes sounding together. Finally hear piano plus bass and decide whether polyphony is spent on layers or saved for chords.

Common misconceptions

That voice count only limits chords; that mono is always simpler, when glide and dynamics are harder to control on a single line; that long releases do not consume voices.

Sources

• Gordon Reid, Sound On Sound Synth Secrets — monophonic and polyphonic behaviour checked, not quoted
• Curtis Roads, The Computer Music Tutorial — voice allocation checked, not quoted

Used for fact-checking only; all prose is original.