furnace/doc/4-instrument/su.md

tildearrow Sound Unit instrument editor

this instrument editor has two tabs.

Sound Unit

for sample settings, see the Sample instrument editor.

the differences are:

• the lack of an "Use wavetable" option
• the presence of a "Use sample" one
• the presence of a "Switch roles of frequency and phase reset timer" option. when enabled, this writes frequency to the phase reset timer register rather than the frequency register
  • this may be used to create sync-like effects.

Macros

• Volume: volume sequence.
• Arpeggio: pitch sequence.
• Duty/Noise: waveform duty cycle sequence.
• Waveform: select waveform.
  • 0: pulse wave
  • 1: sawtooth
  • 2: sine wave
  • 3: triangle wave
  • 4: noise
  • 5: periodic noise
  • 6: XOR sine
  • 7: XOR triangle
• Panning: stereo panning sequence.
• Pitch: fine pitch.
• Phase Reset: trigger restart of waveform.
• Cutoff: set filter cutoff.
• Resonance: set filter resonance.
  • values that are too high may distort the output!
• Control: filter parameter/ring mod sequence.
  • band pass: a band-pass filter. cutoff determines which part of the sound is heard (from bass to treble).
  • high pass: a high-pass filter. higher cutoff values result in a less "bassy" sound.
  • low pass: a low-pass filter. the lower the cutoff, the darker the sound.
  • ring mod: enable ring modulation with previous channel.
    • note: square wave goes from 0 to volume, so in that case it acts more like amplitude modulation.
• Phase Reset Timer: sets the phase reset timer.
  • if the "Switch roles of frequency and phase reset timer" option in the Sound Unit tab is enabled, this macro controls the frequency register instead.