def ks_synth(freq):
"""
Synthesize the given frequency into a Stream by using a model based on
Karplus-Strong.
"""
ks_mem = (sum(lz.sinusoid(x * freq) for x in [1, 3, 9]) +
lz.white_noise() + lz.Stream(-1, 1)) / 5
return lz.karplus_strong(freq, memory=ks_mem)
def ks_synth(freq):
"""
Synthesize the given frequency into a Stream by using a model based on
Karplus-Strong.
"""
ks_mem = (sum(lz.sinusoid(x * freq) for x in [1, 3, 9]) +
lz.white_noise() + lz.Stream(-1, 1)) / 5
return lz.karplus_strong(freq, memory=ks_mem)
inoisy = chain.from_iterable(repeat(inoisy_thub).limit(starting_beats))
smix.add(.1 * s, inoisy)
smix.add(starting_beats * beat_duration - dur, []) # Event timing
# Wavetable lookup initialization
square_table = TableLookup([1] * 256 + [-1] * 256)
harmonics = dict(enumerate([1, 3, 2, 1, .3, .1, .7, .9, 1, 1, .5, .4, .2], 1))
table = sin_table.harmonize(harmonics).normalize()
mem_table = (3 * saw_table + (sin_table - saw_table)**3).normalize()
# Notes synth
midi_tuning = str2midi([gs.tune for gs in guitar])
midi_pitches = [midi_tuning[string_idx] + fret for string_idx, fret in notes]
for freq in midi2freq(midi_pitches):
ks_memory = .1 * gauss_noise() + .9 * mem_table(freq * Hz)
ks_snd = distortion(karplus_strong(freq * Hz, tau=.2 * s,
memory=ks_memory))
tl_snd = .5 * table(freq * Hz) * env
smix.add(dur, .5 * ks_snd + .5 * tl_snd)
# Shows synthesis wavetables
pylab.subplot(2, 1, 1)
pylab.plot(table.table)
pylab.title("Table lookup waveform")
pylab.axis(xmax=len(table) - 1)
pylab.subplot(2, 1, 2)
pylab.plot(mem_table.table)
pylab.title("Karplus-strong memory (besides noise)")
pylab.axis(xmax=len(mem_table) - 1)
pylab.tight_layout()
pylab.show()
smix.add(.1 * s, inoisy)
smix.add(starting_beats * beat_duration - dur, []) # Event timing
# Wavetable lookup initialization
square_table = TableLookup([1] * 256 + [-1] * 256)
harmonics = dict(enumerate([1, 3, 2, 1, .3, .1, .7, .9, 1, 1, .5, .4, .2], 1))
table = sin_table.harmonize(harmonics).normalize()
mem_table = (3 * saw_table + (sin_table - saw_table) ** 3).normalize()
# Notes synth
midi_tuning = str2midi([gs.tune for gs in guitar])
midi_pitches = [midi_tuning[string_idx] + fret for string_idx, fret in notes]
for freq in midi2freq(midi_pitches):
ks_memory = .1 * gauss_noise() + .9 * mem_table(freq * Hz)
ks_snd = distortion(karplus_strong(freq * Hz,
tau=.2 * s,
memory=ks_memory))
tl_snd = .5 * table(freq * Hz) * env
smix.add(dur, .5 * ks_snd + .5 * tl_snd)
# Shows synthesis wavetables
pylab.subplot(2, 1, 1)
pylab.plot(table.table)
pylab.title("Table lookup waveform")
pylab.axis(xmax=len(table) - 1)
pylab.subplot(2, 1, 2)
pylab.plot(mem_table.table)
pylab.title("Karplus-strong memory (besides noise)")
pylab.axis(xmax=len(mem_table) - 1)
pylab.tight_layout()
pylab.show()
step = 60. / beat * s
# Open the choral file
choral_file = corpus.getBachChorales()[random.randint(0, 399)]
choral = corpus.parse(choral_file)
print u"Playing", choral.metadata.title
# Creates the score from the music21 data
score = reduce(operator.concat,
[[(pitch.frequency * Hz, # Note
note.offset * step, # Starting time
note.quarterLength * step, # Duration
Fermata in note.expressions) for pitch in note.pitches]
for note in choral.flat.notes]
)
# Mix all notes into song
song = lz.Streamix()
last_start = 0
for freq, start, dur, has_fermata in score:
delta = start - last_start
if has_fermata:
delta *= 2
song.add(delta, lz.karplus_strong(freq, memory=ks_mem(freq)) * lz.ones(dur))
last_start = start
# Play the song!
with lz.AudioIO(True) as player:
song = song.append(lz.zeros(.5 * s)) # To avoid a click at the end
player.play(song, rate=rate)
