In Unison and Mono modes, playing legato (connecting your notes together by striking a new key before you’ve fully released the last one) can affect the PolyBrute’s envelopes in two ways:
Legato On: Legato notes do not retrigger the envelopes, i.e. you have to fully release all keys before playing a new one will retrigger.
Legato Off: All note-ons retrigger the envelopes regardless of how they’re played.
Legato On can add expressiveness to your playing. For example, let’s say a Preset’s notes begin with a pronounced filter attack-decay that makes a “wow” sound. By varying your playing, you can determine note by note whether this is heard.
Single, Layer, or Split. Most of what the Timbrality button does is covered in our Splits and Layers FAQ. An additional function is that holding it (which mode it’s in doesn’t matter) brings up polyphonic voice allocation options for the lower part.