User Guide

18
FILTER (Continued)
ENV AMT IN
A control signal connected to this input can be used to vary the value of
the ENVELOPE AMT knob.
CUTOFF IN
A control signal connected to this input can be used to vary the value of the
Filter’s Cutoff frequency.
ENVELOPE (ADSR)
Sounds change over time. How they change over time is part of what
makes each one unique. Some sounds begin abruptly, like the strike of
a drum. Some sounds end just as quickly, and some linger like a held
chord on a piano. We call this the envelope of a sound. Grandmother
uses an Envelope generator to create a control voltage that will change
over time. This control voltage is then applied to the volume of the
sound. This same control voltage can be used to affect the Cutoff
frequency of the Filter over time, creating changes in timbre, or tone.
Regardless of how the Envelope is applied, there are four main stages:
ATTACK time, DECAY time, SUSTAIN level, and RELEASE time
.
amplitude
attack
decay
sustain
release
time