Additive

The additive sound engine creates complex digital sounds by combining up to 32 sine waves with various frequencies and amplitudes.

../_images/synthesis-additive.png

A partial is a sine wave whose pitch is a multiple of the note frequency. On the left side of the screen is a visualisation of the frequency (horizontal) and amplitude (vertical) of all active partials.

Partials are sorted into four groups and each group has a volume parameter and an envelope:

  1. the fundamental: 1

  2. all octaves: 2, 4, 8, 16, 32

  3. all odd partials (except 1): 3, 5, 7, 9 etc..

  4. all even partials (except octaves): 6, 10, 12, 14, 18 etc..

  • partials sets the highest partial that is enabled. Higher values will result in brighter sounds while lower values will result in darker sounds.

  • odd space sets the distance in frequency between the odd partials.

  • even space sets the distance in frequency between the even partials.

Tip

When both odd space and even space are set to 100% the partial’s frequencies follow the harmonic series and create a sawtooth sound. By lowering the volume of the odd partials to -inf a square wave sound can be created. When both odd space and even space are set to 0% all partials are the note frequency and using detune an 32 voice sine unison can be created.

  • peak sets which partials is the loudest. Sweeping this parameter has similar effects to sweeping a resonant filter cutoff.

  • comb filt. applies a comb shape of variable width to the partials amplitudes.

  • scatter adds a random delay to the start of each group’s envelope.

  • detune adds a random pitch deviation to each individual partial.