Transient Designer
7
Tech Talk
The SUSTAIN control circuitry
The SUSTAIN control circuitry includes two further envelope
generators. The envelope follower Env 3 (Diagram 4), again
follows the shape of the original curve.
For a longer period the envelope generator Env 4 (Diagram 4)
holds the sustain level according to the peak level and the VCA
control voltage is generated by the difference between Env 3
(Diagram 4) and Env 4 (Diagram 5: hatched area).
The sustain is extended at positive settings and shortened at
negative settings.
Diagram 3
illustrates the shapes of the
processed curves with maximum
and minimum attack, compared to
the original curve from Diagram 1
Diagram 4
illustrates the original curve and
both envelopes generated for
processing the sustain period.The
envelope follower Env 3 corre-
sponds to the original curve.The
sustain of Env 2 is extended
Diagram 5
illustrates the difference between
Env 4 and Env 3. It determines the
VCA control voltage
