1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
|
"""
07-hilbert-transform.py - Barberpole-like phasing effect.
This example uses two frequency shifters (based on complex
modulation) linearly shifting the frequency content of a sound.
Frequency shifting is similar to ring modulation, except the
upper and lower sidebands are separated into individual outputs.
"""
from pyo import *
class ComplexMod:
"""
Complex modulation used to shift the frequency
spectrum of the input sound.
"""
def __init__(self, hilb, freq):
# Quadrature oscillator (sine, cosine).
self._quad = Sine(freq, [0, 0.25])
# real * cosine.
self._mod1 = hilb["real"] * self._quad[1]
# imaginary * sine.
self._mod2 = hilb["imag"] * self._quad[0]
# Up shift corresponds to the sum frequencies.
self._up = (self._mod1 + self._mod2) * 0.7
def out(self, chnl=0):
self._up.out(chnl)
return self
s = Server().boot()
# Large spectrum source.
src = PinkNoise(0.2)
# Apply the Hilbert transform.
hilb = Hilbert(src)
# LFOs controlling the amount of frequency shifting.
lf1 = Sine(0.03, mul=6)
lf2 = Sine(0.05, mul=6)
# Stereo Single-Sideband Modulation.
wetl = ComplexMod(hilb, lf1).out()
wetr = ComplexMod(hilb, lf2).out(1)
# Mixed with the dry sound.
dry = src.mix(2).out()
s.gui(locals())
|
