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Making Other Synth Drum Sounds
In the Making an Oscillator patch, we created a kick drum which decays to an inaudible frequency
below the range of human hearing. To create a higher-pitched drum, such as a tom-tom, we will need a
VCA to cut off the audio after the drum decays. Using a VCA also gets rid of the clicking between drum
hits which happens when not using a triangle wave.
Raise the pitch of Channel A using the sliders or Channel B’s
Offset
knob. You should hear a steady
tone between Channel B firing (this is especially noticeable if you’re using external triggers). Now we’ll
route this sound through Channel B’s VCA. Unpatch the cable going to the mixer and patch it into
Audio Out B
instead. Patch a cable from
ENV A
to
Audio In B.
Now you should hear a similar synth
drum sound, but it will be silent between hits.
Try setting Channel B’s
Shape
slider to various positions left of center and listen how the “punch” of the
drum changes. As you do this, you may need to adjust Channel B’s
Offset
knob to keep the pitch in the
desired range. You may also want to patch Channel B’s
Lin 5V
to its
VCA CV
so that the VCA’s
response doesn’t change as you adjust the
Shape
slider.
To get more complex waveshapes, patch
EOR
to Channel A’s
Shape
CV jack and adjust the
Shape
knob (see Different Waveshapes for Rise and Fall patch on page 11)
To add some noise to the drum sound, you can patch an external oscillator into
Audio In A.
Then move
the patch cable going from
ENV A
to
Audio In B
so that it goes from
Audio Out A
to
Audio In B
. The
external oscillator will be amplitude modulated (AM) with the synth drum sound, and this resulting
sound will be VCA’ed with Channel B’s envelope. Play with Channel A’s sliders and
Rise/Fall
CV knobs
to hear the range of possible sounds. Next, use the
OR
output jack to modulate the external oscillator in
time with the synth sound.
Try adding slight modulation to the
Time
CV
or
Shape
CV of Channel B to create organic, naturally
changing drum sounds. A slow LFO or a CV sequencer will work nicely.
Page of
14
24
Cycle
AR
ASR
Cycle
AR
ASR
Rise
Fall
Shaped Dual EnvVCA
Time
Time
Follow
VCA CV
VCA CV
In
Audio B
Audio A
Out
In
Out
Lin 5V
Lin 5V
OR
Shape
Rise
Fall
Slow
Fast
Med
Slow
Fast
Trig
Cycle
Offset
Level
EOF
Fall
Rise
Shape
Shape
Follow
ENV A
ENV B
Shape
Fall
Rise
Slow
Fast
Med
Slow
Fast
Trig
Cycle
Offset
Level
EOR
A
Cycle
on if not using
external trigger
To mixer/output amp
Cycle
on
Both switches
set to
Fast
.
Rise
and
Fall
sliders control
attack and decay of
kick drum
Rise
and
Fall
Sliders set the
base pitch and
timbre
Rise/Fall
CV
fully to the left
Rise
switch to
Fast
.
Fall
switch to
Med
.
Level
controls
amount of
modulation
Level
controls
volume
From external trigger
source (gate
sequencer, clock, …)
Shape
slider
and knob
change timbre
Optional: Move
Shape
slider towards
expo for more punch
Offset
at center.
Optional: to
Audio In B
Optional:
Sound source
to be AM’ed