Reference Manual
CHAPTER 22. LIVE INSTRUMENT REFERENCE 343
note pitch, be xed or be set to something in between. This is dened by the Rate<Key
parameter in the LFO's display.
The intensity of the LFO is set by the LFO Mod control in the shell. This parameter can be
modulated by note velocity via the display's Amt<Vel control. The LFO's intensity is also
affected by its envelope.
22.6.4 Envelopes
Operator has seven envelopes: one for each oscillator, a lter envelope, a pitch envelope
and an envelope for the LFO. All envelopes are constructed similarly and feature some
special looping modes.
Each oscillator's volume envelope is dened by six parameters: three rates and three levels.
A rate is the time it takes to go from one level to the next. For instance, a typical pad sound
starts with the initial level -inf dB (which is silence), moves with an attack rate to its peak
level, moves from there to the sustain level with a decay rate, and then nally, after note-off
occurs, back to -inf dB at the release rate. Operator's display provides a good overview of
the actual shape of any particular envelope and lets you directly adjust the curve by clicking
on a breakpoint and dragging. The breakpoints retain their selection after clicking, allowing
them to be adjusted with the keyboard's cursor keys, if desired.
Hint: Envelope shapes can be copied and pasted from one oscillator to another in Operator
using the
(PC) /
Ctrl
(Mac) context menu.
With FM synthesis, it is possible to create spectacular, endless, permuting sounds; the key
to doing this is looping envelopes. Loop Mode can be activated in the lower left corner of
the display. If an envelope in Operator is in Loop Mode and reaches sustain level while the
note is still being held, it will be retriggered. The rate for this movement is dened by the
Loop Time parameter. (Note that envelopes in Loop Mode can loop very quickly and can
therefore be used to achieve effects that one would not normally expect from an envelope
generator.)
While Loop Mode is good for textures and experimental sounds, Operator also includes Beat
and Sync Modes, which provide a simple way of creating rhythmical sounds. If set to Beat
Mode, an envelope will restart after the beat time selected from the Repeat chooser. In Beat
Mode, the repeat time is dened in fractions of song time, but notes are not quantized.