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‎Ch. 15 - Modulated Delay Effects/biquadWah.py‎

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# BIQUADWAH
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# This function can be used to create a wah-wah audio effect.
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#
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# Input Variables
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# x: single sample of the input signal
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# Fs: sampling rate
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# lfo: used to determine the frequency of LPF
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# ff: buffer for feedforward delay
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# fb: buffer for feedback delay
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# wet: percent of processed signal (dry = 100 - wet)
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#
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# Use Table 13.1 to calculate LPF bi-quad coefficients.
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#
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# See also BIQUADPHASER
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import numpy as np
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def biquadWah(x, Fs, lfo, Q, ff, fb, wet):
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# Convert value of LFO to normalized frequency
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w0 = 2 * np.pi * lfo / Fs
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# Normalize bandwidth
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alpha = np.sin(w0)/ (2 * Q)
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b0 = (1 - np.cos(w0)) / 2
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b1 = 1 - np.cos(w0)
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b2 = (1 - np.cos(w0)) / 2
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a0 = 1 + alpha
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a1 = -2 * np.cos(w0)
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a2 = 1 - alpha
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# Wet/dry mix
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mixPercent = wet # 0 - only dry, 100 - only wet
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mix = mixPercent/100
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drySig = x
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# All-pass filter
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wetSig = (b0/a0) * x + (b1/a0) * ff[0] + (b2/a0) * ff[1] - (a1/a0) * fb[0] - (a2/a0) * fb[1]
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# Blend parallel paths
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out = (1 - mix) * drySig + mix * wetSig
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# Iterate buffers for next sample
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ff[1] = ff[0]
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ff[0] = x
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fb[1] = fb[0]
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fb[0] = wetSig
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return out, ff, fb

‎Ch. 17 - Amplitude Envelope Effects/.DS_Store‎

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‎Ch. 17 - Amplitude Envelope Effects/AcGtr.wav‎

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‎Ch. 17 - Amplitude Envelope Effects/Amplitude Envelope Effects.ipynb‎

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‎Ch. 17 - Amplitude Envelope Effects/__pycache__/biquadWah.cpython-38.pyc‎

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‎Ch. 17 - Amplitude Envelope Effects/biquadWah.py‎

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# BIQUADWAH
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# This function can be used to create a wah-wah audio effect.
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#
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# Input Variables
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# x: single sample of the input signal
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# Fs: sampling rate
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# lfo: used to determine the frequency of LPF
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# ff: buffer for feedforward delay
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# fb: buffer for feedback delay
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# wet: percent of processed signal (dry = 100 - wet)
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#
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# Use Table 13.1 to calculate LPF bi-quad coefficients.
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#
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# See also BIQUADPHASER
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import numpy as np
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def biquadWah(x, Fs, lfo, Q, ff, fb, wet):
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# Convert value of LFO to normalized frequency
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w0 = 2 * np.pi * lfo / Fs
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# Normalize bandwidth
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alpha = np.sin(w0)/ (2 * Q)
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b0 = (1 - np.cos(w0)) / 2
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b1 = 1 - np.cos(w0)
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b2 = (1 - np.cos(w0)) / 2
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a0 = 1 + alpha
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a1 = -2 * np.cos(w0)
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a2 = 1 - alpha
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# Wet/dry mix
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mixPercent = wet # 0 - only dry, 100 - only wet
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mix = mixPercent/100
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drySig = x
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# All-pass filter
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wetSig = (b0/a0) * x + (b1/a0) * ff[0] + (b2/a0) * ff[1] - (a1/a0) * fb[0] - (a2/a0) * fb[1]
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# Blend parallel paths
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out = (1 - mix) * drySig + mix * wetSig
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# Iterate buffers for next sample
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ff[1] = ff[0]
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ff[0] = x
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fb[1] = fb[0]
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fb[0] = wetSig
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return out, ff, fb

‎Ch. 17 - Amplitude Envelope Effects/testing.py‎

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‎Ch. 18 - Dynamic Range Processors/AcGtr.wav‎

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‎Ch. 18 - Dynamic Range Processors/Dynamic Range Processors.ipynb‎

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‎Ch. 18 - Dynamic Range Processors/Kick.wav‎

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