def apply_filt (x, fs, freq, Q, gain):
filt = adsp.Filter(2, fs)
y = np.zeros_like(x)
b, a = adsp.design_bell(freq, Q, 10**(-60/20), fs)
filt.set_coefs(b, a)
for n in range(len(x)):
curGain = gain**n
y[n] = filt.process_sample(x[n]) * (1.0 - curGain) + x[n] * curGain
return y
def add_bell(self, fc, Q, gain):
"""
Add a bell filter to the EQ
Parameters
----------
fc : float
Cutoff frequency
Q : float
Q factor
gain : float
gain in linear units
"""
string = 'Bell, Freq: {}, Q: {}, gain: {}'.format(fc, Q, gain)
filter = adsp.Filter(2, self.fs, type=string)
b, a = adsp.design_bell(fc, Q, gain, self.fs)
filter.set_coefs(b, a)
self.add_filter(filter)
def test_eq_bell_design(self):
b, a = adsp.design_bell(_fs_ / 2, 0.707, 1, _fs_)
checkCoefs(self, b, a, [1, 2, 1], [1, 2, 1])
def static_filt(freq, bandwidth, gainDB, sig):
sig_filt = np.copy(sig)
b,a = adsp.design_bell(freq, freq/bandwidth, 10**(gainDB/20), fs)
sig_filt = signal.lfilter(b, a, sig_filt)
return sig_filt
def time_bell_filter(self):
for _ in range(_num_):
adsp.design_bell(_fc_, _Q_, _gain_, _fs_)
fs = 44100
sweep = adsp.sweep_log(20, 22000, 2, fs)
y = np.copy(sweep)
mags = np.array([0.99, 0.99])
poles = np.array([1000, -1000])
# b, a = design_allpole (mags, poles, fs=fs)
#%%
freqs = np.logspace(1, 3.4, num=1000, base=20)
for g in [0.00001, 0.001, 0.01, 0.1, 0.5, 0.8]:
cur_sweep = np.copy(sweep) * g
y = np.copy(cur_sweep)
filter = Biquad()
b, a = adsp.design_bell(1000, 0.707, 2, fs)
filter.setCoefs(b, a)
# filter.set_coefs (a)
filter.fb_lambda = lambda a, x: a * np.tanh(x) # adsp.soft_clipper (x)
y = filter.process_block(y)
h = adsp.normalize(adsp.sweep2ir(cur_sweep, y))
adsp.plot_magnitude_response(h, [1], worN=freqs, fs=fs)
# plt.ylim (-15)
#%%
filter = AllPole()
filter.set_coefs(a)
filter.fb_lambda = lambda a, x: a * adsp.soft_clipper(x)
y = filter.process_block(y)