Sequential Prophet X - TAB 4 - LPF Misc; Filter Envelope

36 37Filter
Sequential Prophet X User’s Guide
Filter Envelope
TAB 4 - LPF Misc
Stereo Split
Stereo Split DriveResonance Key>LPF Freq
0
LP FilterVCF ADSR
LPF MiscVCF Env Amt
Stereo Split: +82... -82—This offsets the lter cutoff frequency between
the Prophet X’s stereo lters. Turning the knob clockwise simultaneously
increases the cutoff frequency in the left channel and reduces the cutoff
frequency in the right channel. Conversely, turning the knob counter-
clockwise simultaneously increases the cutoff frequency in the right
channel and reduces the cutoff frequency in the left channel. This can be
useful for creating additional depth in the stereo eld. This control has no
effect in 16-voice mode since the signal path is monophonic.
Filter Envelope
The Prophet X lter has a dedicated, 5-stage envelope generator (ADSR
plus delay). The Filter Envelope is used to shape the harmonic charac-
teristics of a synthesized sound by giving you ltering control over its
attack, decay, sustain, and release stages.
This is one of the most important aspects of designing a sound. Without
an envelope, the lters would be completely static. They would stay open
or closed by a xed amount that wouldn’t change over the duration of
a sound. That’s not very interesting to listen to and not how real-world
instruments behave.
In general, sounds produced by an instrument are brighter at their begin-
ning (the attack stage) and grow mellower as they die out (the decay and
release stages). In other words, their harmonic content changes over time.
This is exactly what the lter envelope is designed to emulate.
Filter Envelope
attack decay sustain release
amplitude
time
note offnote on
delay
A typical 5-stage DADSR envelope