11.3

Table Of Contents

SUBTRACTOR SYNTHESIZER282

When phase offset modulation is activated, the oscillator creates a

second

waveform of the same shape and offsets

it by the amount set with the Phase knob. Depending on the selected mode, Subtractor then either subtracts or mul-

tiplies the two waveforms with each other. The resulting waveforms can be seen in the illustration below.

• In example 1, we see two sawtooth waves with a slight offset.

• Example 2 shows that subtracting one slightly offset sawtooth wave from the other, produces a pulse wave. If

you modulate the Phase offset parameter (with for example an LFO), the result will be pulse width modulation

(PWM).

• Example 3 shows the resulting waveform when multiplying the offset waves with each other. As you can see

(and hear if you try it), multiplying waveforms can produce very dramatic and sometimes unexpected results.

Using phase offset modulation can create very rich and varied timbres, especially when used along with LFO or En-

velopes to modulate the phase offset.

q To get a “feel” for this concept, you could study Patches that use phase offset modulation, and maybe tweak

some of the Phase Offset parameters to find out what happens. Try “SyncedUp” in the Polysynth category in

the Factory Soundbank for an example of osc sync or “Sweeping Strings” (in the Pads category) for an exam-

ple of PWM.

! Note that if you activate waveform subtraction with a Phase offset set to “0” for an oscillator, the second wave-

form will cancel out the original waveform completely, and the oscillator output will be silent. If you set the

Phase Offset knob to any other value than zero, the sound returns.

1. The two offset

waveforms:

1. The two offset

waveforms:

2. The result of

subtraction:

3. The result of

multiplication:

Ampl.