Lexicon PCM 80 - Manual (Page 83)

3-25
The Algorithms and Their Parameters
Mod: AR Env
This envelope generator's output, when turned on, will go from 0 to127. How
quickly it goes from 0 to 127 is determined by the setting of Attack (0-10
seconds). Once the envelope generator has reached 127, it remains there as
long as it is turned on. When it is turned off, it goes from 127 to 0, at the rate
determined by Release (0 to 10 seconds).
T Src allows you to select a Source to turn the envelope generator on and off.
T Lvl allows you to select a specific threshold value which the T Src must reach
to turn the envelope generator on.
The Mode parameter allows you to determine the behavior of the envelope
controller in relation to the threshold value. Four settings are available: Repeat,
One Shot, Retrigger, and Off.
Repeat As long as the threshold source remains at or above T Lvl,
the envelope cycles from attack to release. If A=R, the
output of the envelope is a triangle wave.
One Shot Once T Lvl is reached, the envelope will go through its
entire attack cycle. Once the attack cycle is completed, if
Source value is below T Lvl, the envelope will immediately
fall at the specified Release rate. The envelope will go
through its entire release cycle, even if the source subse-
quently rises above T Lvl. If the Source value is at or above
T Lvl, the envelope will remain at 127 until the T Src falls.
Retrigger As long as the level is at or above T Lvl, the envelope will
go through its attack cycle. If the level falls below T Lvl
before attack is completed, the envelope immediately be-
gins to release.Likewise, if the T Lvl is crossed again before
the release is completed, the attack cycle will begin again.
Off This control turns the AR envelope off (and frees up proces-
sor time). To optimize PCM 80 real-time response, set AR
Env to Off when it is not being used.
Mod: Env L and Mod: Env R
These are left and right input signal envelope followers. The only available
parameter is Release which is set in milliseconds. This control allows you to
specify the release rate (0-10 seconds) when the input level drops.
Modulation cont'd.