It has an oscillator, which you can
ask to output either saw-waves or square-waves. The
output of the oscillators goes into a variable
frequency filter with optional resonance. Finally
the output of the filter is multiplied by a slow,
fixed-time envelope. Tweaking the knobs is
The oscillator will simply track the
latest MIDI note-on message, so you'll probably want
to sequence it. MIDI note-off messages matching the
current note will gate the amplitude envelope.
Overlapped notes won't retrigger the envelopes, and
will cause the oscillator to slide to the new pitch.
Notes with high velocity (about 101 and up) will
trigger "accents" (these can be sliding notes too,
or even half-way through the same note if you manage
to convince your host not to send note-off in the
middle), which will temporarily set the filter
envelope timing to minimum and depending on the
accent knob (and for slides also the remaining level
of the filter envelope) boost volume and cutoff a
Dolphin Bassline is free.