Like LFClipNoise, it generates the values -1 or +1 at a rate given by the
freq argument, with two differences:
If you don't need very high or very low freqs, or use fixed freqs, LFDClipNoise is more efficient.
Approximate rate at which to generate random values.
Output will be multiplied by this value.
This value will be added to the output.
freqargument only when scheduled; thus they often seem to hang when freqs get very low.