an example can be found on AMOSPro_Examples:Examples/H-7/Help_75.AMOS
Selects one or more voices ready to perform, by setting its individual bit mask to 1.
Voice %1111 : Rem Activate all four voices
Four voices can be used to play your sound. Each voice to be played must have its associated bit set to 1.
Bit0-> Voice 0
Bit1-> Voice 1 Bit2-> Voice 2 Bit3-> Voice 3