TRAX RetroWave Owner’s Manual
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How the Sample and Hold section works
ADSR
receives a one-shot waveform from the
ADSR
generator, to provide a variable amount of pitch
shifting when each new note is played. This effect is often heard in panpipes, train steam whistles, and
human whistling (synth maestro Isao Tomita used this effect a lot on his studio albums).
PWM Sources
This row of dials is used to control the pulse width of the square wave signal only.
MAN.
is the manual shape control, mentioned previously.
LFO 2
injects the selected LFO 2 waveform, giving continuous modulation of pulse width. A small
amount of signal gives a mild, but interesting variation to the sound, while larger amounts create a
chorus effect, as if two oscillators were playing in unison.
Note that when this control is set at or near maximum, and the manual shape control is near one
extreme or the other, dropouts in the signal can occur as the square wave is “pushed” out of its normal
pulse width range by the control signal. This is not a fault, and can indeed be useful for creating some
unusual sounds.
ADSR
applies the
Attack – Decay – Sustain – Release
waveform, giving a one-shot variation to the
pulse width each time a note is played. Careful adjustment of this control and the ADSR contour can give
some dramatic effects.
Voltage-Controlled Filter (VCF)
This part of the machine comprises an
audio mixer with a voltage-controlled, 4-
pole, 24dB per octave filter.
If there is one factor that differentiates
the synthesizer from any other type of
instrument, dynamic filtering has to be
it. Not only are some of the most
extreme effects produced using this
section, but also some of the most
Random
noise signal
Command
pulses derived
from LFO 1
Random
voltage
output
