Introduction.
2
The SD909 module is an exact recreation of the original TR-909 snare drum
analog sound generators adapted for modular synthesizer use. The front panel
contains all of the controls found on the original TR-909 drum machine, in addition
we have added more controls to further enhance the sound palette of this great
analog circuit. The SD909 also includes the TR-909 white noise generator as an
extra sound source in the system, and unlike the TR-909, the noise source in
the SD909 is voltage controlled.
Plug the SD OUT to a mixer, set the knobs position similar to the drawing below
and hit the Trigger Button.
To set the exact sound of the TR909 the sounds from the internal oscillators and
noise generator need to be balanced correctly. The SD909 NOISE and ACCENT
controls are the main ones controlling that. The front panel has regions marked
with a dot and labeled 909, which are the original settings. Since this is an analog
circuit and tolerance varies we marked regions instead of an exact spot. Go ahead
and turn NOISE all the way up and slowly bring it back toward the dot, as the gain
starts to increase that is where the control needs to be. Set the accent where the
dot is. Now set the SNAPPY to balance the noise vs the oscillators sound.
Let’s get started.
1
2
3
4
5
6
7
8
STEPS
MUTE
CHANNEL
SLOT
PRESET
LP START
LOOP
LP END
ZOOM
OUT
1
2
3
4
5
6
7
8
TAP
BOSS
INT
EXT
BEAT-C
BEAT-P
REVERSE
COPY
CLEAR
PASTE
4x1 6
LENGTH
REVERSE
ZOOM
GLOBAL
REPEAT
TRIG4
TRIG1
FILL
TRIG5
TRIG2
TRIG6
TRIG3
8x8
TRIG7
TRIG8
ST/STOP
VERTICAL
1 x64
SWING
2x32
RESET OUT
CLOCK IN
RESET IN
CLOCK OUT
RANDOM
CLOCK
1
2
3
4
5
6
7
8
M I X Z
GAIN
BUS MIX
OUT B
MIXER B
MIXER A
OUT A
SEQUENCER
SD909
MIXER
