Roland V-Synth Book page 29

One-Shot LFO as Additional Envelope
If LFOs are otherwise not required (e.g. for pitch or formant modulation), they can be put to good use as additional envelopes. Although
there is no special one-shot LFO mode in the V-Synth, this can be simulated using the following trick. Again, this is only an experiment
to show how it works - the sound itself is not particularly useful!
Dive
Start with 512:INIT PATCH and go to OSC1. Touch the LFO tab
and take Rate down to zero
4
. Change the Time value to 40
ramp in the LFO graphic display - this is our extra envelope.
To demonstrate how this could be used to "modify" an envelope, select OSC1 / Pitch
flip Sustain down to zero and change Decay to 64
that the pitch drops at a medium rate
- it appears to be linear. Now change Pit LFO Dp (Pitch LFO Depth) to -27 and play a note
4
. At -27, the rising LFO (it was falling, but the modulation depth is negative) cancels out
the first part of the envelope exactly, and you end up with a plateau as long as the LFO
Time parameter, followed by the rest of the "dive" caused by the envelope.
Of course you can make the one-shot LFO have the opposite effect, e.g. adding it to the
normal filter envelope for an additional short "pluck" at the beginning of each note.
Inverse Envelopes
Not many people ever consider putting envelopes upside-down, although this can be
very useful sometimes. The individual segments change their meanings completely:
A
becomes a decay to minimum after an instantaneous attack
D
becomes a rising slope if the S value is not 127 (minimum!)
S
is inverted i.e. maximum becomes minimum and vise-versa
R
becomes a final rising slope
3
. Activate both Key Sync and the "ON>>" Fade button
5
. You should now see a short downward sloping
2 . Take Env Depth up to +40 so
3 . Play a note and listen to the shape of the decay
1 , select SQR 2
1
1
,
1
Normal Envelope
A D
2
3
4
4
5
3
2
Pitch Envelope
One Shot LFO
(Pit LFO Dp=-27)
Result of addition
Reverse Envelope
S
S
R A D R
Next
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