Moog Music Voyager Old School - Manual (Page 40)

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Voyager OS User’s Manual - Appendices
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Voyager OS User’s Manual - Appendices
To produce a modulated fi lter effect:
Using a patch cord, make a connection from the CP-251 Attenuator Output jack to the Voyager’s
FILTER jack. On the CP-251, set the LFO RATE control to 6 Hz (about 1 o’clock), and adjust the
ATTENUATOR to about ‘2’ on the dial. This will produce a cyclical tonal variation as the fi lter cutoff
frequency is modulated. Setting the CP-251’s LFO RATE control considerably higher will result in
wild timbral textures, while a very low setting will create a slowly evolving fi lter sweep.
2. Inverting the keyboard CV to the Filters
This is a handy little trick that can be used to lower the fi lter cutoff as you play higher on the keyboard. This
effect mimics certain acoustic instruments like a cello, whose tone gets duller as higher notes are played.
- Set the panel controls to the default confi guration.
- Turn the Voyager Filter KB. CONT. AMOUNT control to ‘0’
- Using a patch cord, connect the VX-351 KBD PITCH output to the CP-251 Attenuator Input.
- With a second patch cord, connect the Attenuator output to the Voyager’s FILTER jack.
- Set the CP-251’s ATTENUATOR control level to -5.
Play a scale up the keyboard, from low to high, and you’ll notice that the sound gets much duller. Adjust the
FILTER CUTOFF and ATTENUATOR controls to taste.
3. Creating Sample and Hold staircase patterns
A Sample and Hold circuit can be used for more than generating random voltages. One type of modulation
pattern that can be achieved is called ‘Staircase’ modulation. It is achieved by feeding a slow triangle wave
into the Sample and Hold circuit and sampling that input at a high rate, effectively chopping the triangle
wave into discreet voltage levels that resembles a staircase. We’ll use two LFO’s for this; a slow one for the
input and a fast one for the trigger.
- Set the panel controls to the default confi guration.
- Set the Voyager’s LFO rate to about .4 Hz.
- Using a patch cable, make a connection from the VX-351’s LFO triangle output jack to the
Voyager’s Sample and Hold Input jack (S&H IN).
- Set the CP-251’s LFO RATE control to about 6 Hz (about 1 o’ clock on the dial).
- Using another patch cable, make a connection from the CP-251’s LFO square wave output jack to
the Voyager’s Sample and Hold Gate Input jack (S&H GATE).
- Set the Voyager’s LFO WAVE control to the S&H position.
- Set the Mod Bus 1 controls as follows:
SOURCE: LFO
DESTINATION: PITCH
CONTROLLER: MOD WHEEL
AMOUNT: 6
Play a note and move the Mod Wheel forward. You should hear the pitch modulated by an ‘up & down’
staircase waveform.