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Set both
Offset
knobs to center so that the envelope will start and end
at 0V. Set Channel A’s
Level
knob to 2:30, which should produce an
envelope with a 5V amplitude on the
ENV
jack. Channel B’s
Level
knob
controls the sustain level, it must stay between 12:00 and 2:30. Try 1:00
to start.
To keep things simple, start with the
Shape
sliders both centered. Once
you dial in a sound, feel free to adjust them in order to make more
complex ADSR shapes.
When a gate is fired into the
Trig
jacks, an ADSR envelope will be
output from the
OR
output jack. Patch the
OR
jack to Channel A’s
VCA
CV
jack. Patch an audio signal into
Audio In A
, and patch
Audio Out A
to a mixer.
If you want to use the ADSR envelope elsewhere in you can split or mult
the
OR
output.
Play with sending gates of different pulse widths. Play with the sliders to
adjust the segment times. Remember to keep both
Rise
sliders at the
same position or else you’ll get an envelope with extra segments. Play
with Channel B’s
Level
knob to change the sustain level. Remember to
keep it between 12:00 and 2:30 or else you’ll get a simple AR or ASR
envelope.
The way this patch works is illustrated in Figure 10. The blue trace is the input gate which triggers
Channel A (green) to make an AR envelope, and Channel B (magenta) to make an ASR envelope. The
ASR envelope is attenuated more than the AR envelope (due to Channel B’s
Level
knob being lower
than Channel A’s). When these two envelopes are mixed together via an analog OR operation, the
result is an ADSR envelope. The rise and fall of the AR envelope set the A and D segments; the sustain
and fall of the ASR envelope set the S and R segments.
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Figure 10: ADSR (orange)
formed from components: AR
(green) and ASR (magenta). Blue
is gate input.