User Manual

Wah Effects (Orange) 147
Wah Rate
Reducer
This effect reduces the sampling rate of the audio signal passing through. The sampling
frequency is controlled with the “Manual” parameter. Lowering the sample rate results in a
raspy, scratchy quality as well as aliasing. Use the “Peak” parameter to continuously control
the quality of the sample rate interpolation, which will alter the harmonic content drastically.
Wah Ring
Modulator
Here, the signal is modulated by a sine oscillator. The pitch of the oscillator is controlled with
the “Manual” parameter - note that the “Manual” parameter is bipolar, therefore a setting of
“0” will have no effect. Lower settings produce a tremolo-like effect, whereas higher settings
bend the complete harmonic structure of the instrument into a bell-like character by shifting
every frequency component either upwards (sum frequency) or downwards (difference
frequency).
The “Stereo” parameter divides the sum and difference frequencies between the left and
right channels. The bipolar nature of the “Manual” parameter can now be used to reverse the
stereo panorama. As usual, the “Mix” parameter adds the direct signal. With “Mix” in the
middle position, the ring modulation becomes amplitude modulation.
Wah Frequency
Shifter
The frequency shifter is a rarely seen effect and can be thought of as a “deluxe” ring
modulator. Even today, only a handful of frequency shifters exist in the digital domain.
It is as useful in creating beautiful, subtle harmonic deviations as it is in producing high-
pitched, clangorous noise. Like the ring modulator, it uses a sine wave to modulate the
signal, but in such a way as to produce only the “sum” or “difference” frequencies of the two
signals. In contrast to a pitch shifter, which preserves the dependencies of the harmonics,
the frequency shifter bends these dependencies, resulting in a bell-like spectrum. It’s not
unlike a shortwave radio that has not been tuned correctly.
Use the “Manual” parameter to determine the pitch of the sine wave. This is a bipolar
parameter where the center position (0) will result in no audible frequency shifting.
Turning “Manual” clockwise results in a linear frequency shift upwards, while turning it
counter-clockwise results in a downwards shift. Note how the shifted signal loses its
harmonic structure.
When “Manual” is adjusted to the far left, you will notice that the pitch starts to rise again.
This is the result of frequencies being shifted past zero Hz, which causes them to be
mirrored upwards.
The “Stereo” parameter allows continuous adjustment of the phase of the left and right
channels, thereby creating a subtle, or blatant, stereo-widening effect.