The base-width filter defines a frequency band by center and bandwidth rather than cutoff and slope

The Digitakt II’s FLTR Page 2 hosts a secondary ‘base-width’ filter in addition to the swappable main filter machine. BASE sets the lower edge of the passed frequency band; WIDTH sets the span above BASE. This is a bandpass-style control paradigm: rather than a single cutoff, you define both the floor and ceiling of the allowed band. Edge cases: BASE=0 → low-pass (WIDTH sets cutoff); WIDTH=127 → high-pass (BASE sets cutoff); BASE=0 + WIDTH=127 → flat (no filtering). BW.RT (routing) selects whether the base-width filter runs before (PRE) or after (POST) the main filter machine. The base-width filter allows sculpting a frequency window (e.g., isolating a mid-range band) that the main filter can then further shape. All parameters are p-lockable.

Examples

Set BASE=30, WIDTH=60 to carve a mid-range window. Then use a resonant lowpass on the FLTR Page 1 to sweep within that window. Set BW.RT=PRE so the bandpass restricts input to the main filter.

Assessment

If BASE=0 and WIDTH=127, what does the base-width filter do? What routing (PRE vs POST) would you use if you want the main filter to operate on a pre-limited frequency band?