01_01_3
additional parameters: if1, if2

 
This instrument is derived from Risset's 'Linear and Exponential
Decay Experiments'. The object of the comparison here are two
types of decay and four different durations: middle (2 sec), long
(4 sec), short (1 sec) and shorter (.5 sec). 

Linear decay seems to occur slowly at first and then suddenly
disappears; exponential decay is more even and gives a resonance
impression.

To avoid cutoff during exponential decay, one has to ensure that
the amplitude controlling function decays to a final value not
smaller than the inverse of the maximum amplitude. When the
absolute amplitude becomes smaller than 1, the sound is lost in
the quantizing noise.  For instance, if the maximum amplitude is
8000, one should have a function decaying to 2(**-13)=1/8192. 
(Risset 1969: #300)


(flowchart, envelope functions linear and exponential decay)
(.orc and .sco files)

