Freq – Audio Damage BigSeq2 User Manual
Page 17
frequencies above its cutoff frequency without alteration. As you rotate the frequency knob clockwise,
the signal loses its lower frequencies and the output sounds thinner. If you turn the frequency knob up
far enough, you might not hear anything at all because the entire signal has been filtered out.
Two-pole high pass (shown as “2P HP”): If you've been paying attention you can probably figure this
one out for yourself, right? It's a high-pass filter that has a less steep attenuation curve than the four-
pole high-pass filter. Use it when you want to create a thinner sound without the drastic low-frequency
reduction of the four-pole high-pass filter.
Four-pole band pass (shown as “4P BP”): A band-pass filter allows a range of frequencies centered on
the cutoff frequency to pass and attenuates higher and lower frequencies. The width of the band of
frequencies is controlled by the Resonance control. Wah-wah pedals used by guitarists are based on
band-pass filters.
Freq
The Freq block contains a frequency shifter. A frequency shifter is a somewhat unusual beast in signal
processing and bears some explanation. For starters, a frequency shifter is not the same thing as a pitch
shifter. (If you’re looking for a pitch shifter, we suggest you head to our website at
and read about Discord 2, our powerful and entertaining pitch-shifter plug-in.) The difference is that a pitch
shifter multiplies all of the frequency components of a signal by some number, which preserves their harmonic
relationship to each other. A frequency shifter adds some number to all of the frequency components of the
signal. This means that the harmonics of the signal no longer form the original ratios with each other, and the
timbre of the signal changes, becoming inharmonic and sometimes metallic-sounding
2
. At small shifting
intervals, frequency shifting can create lovely detuning and chorusing effects.
2
Frequency shifting is a close relative of ring modulation, which also produces metallic-sounding timbres. The difference is
that ring modulation creates two sets of frequency components: one set of components of higher frequency than the
original, and one set lower than the original. Frequency shifting creates only one set of frequency components, which can be
higher or lower than the components of the original signal. Hence a frequency shifter sort of creates half of the effect of a
ring modulator. Somewhat paradoxically, a frequency shifter is much more complicated to create—in either software or
hardware—than a ring modulator.