C64 C128 M65
Selects various sound filter properties.
FILTER [<sid_number>] <subcmd> [<subcmd> ...]
<sid_number> is optional and defines on which SID chip the filter values should be set. If it isn't provided, it defaults to 1. This parameter is useful on multi-SID systems, for example a C64 equipped with two SID chips, or the M65 that has four SID chips. The number must be between 1 and 4.<subcmd> is one of:CUTOFF <cutoff_freq> - Filter cutoff frequency, a value between 0-2047RESONANCE <value> - Filter resonance setting, a value between 0-15 LOW|BAND|HIGH PASSNote
Refer to the SID Data Sheet for explanation of all filter settings.
FILTER CUTOFF 900 RESONANCE 7 LOW PASS
The filter can be applied to a particular voice using the VOICE command.