Synthesis

Sound generation using DaisySP, STK, PolyBLEP, and fxdsp backends.

DaisySP oscillators

from nanodsp import synthesis

# Basic waveforms
sine = synthesis.oscillator(frames=48000, freq=440.0, waveform="sine")
saw = synthesis.oscillator(frames=48000, freq=220.0, amp=0.5, waveform="saw")
square = synthesis.oscillator(frames=48000, freq=330.0, waveform="square", pw=0.3)
tri = synthesis.oscillator(frames=48000, freq=440.0, waveform="tri")

# Anti-aliased variants
poly_saw = synthesis.oscillator(frames=48000, freq=440.0, waveform="polyblep_saw")

# Band-limited oscillator
bl = synthesis.bl_oscillator(frames=48000, freq=440.0, waveform="saw")

FM synthesis

Two-operator FM: a modulator oscillator modulates the frequency of a carrier. The ratio controls the modulator/carrier frequency ratio (integers produce harmonic timbres), and index controls the modulation depth.

# Classic FM bell
bell = synthesis.fm2(frames=48000, freq=440.0, ratio=1.4, index=5.0)

# Harmonic FM (integer ratio)
bright = synthesis.fm2(frames=48000, freq=220.0, ratio=2.0, index=3.0)

# Formant oscillator (carrier + formant frequency control)
formant = synthesis.formant_oscillator(
    frames=48000, carrier_freq=110.0, formant_freq=800.0
)

Band-limited oscillators

Aliasing-free oscillator algorithms for clean digital synthesis:

# PolyBLEP -- efficient, 14 waveforms
saw = synthesis.polyblep(frames=48000, freq=440.0, waveform="sawtooth")
sq = synthesis.polyblep(frames=48000, freq=440.0, waveform="square")
tri = synthesis.polyblep(frames=48000, freq=440.0, waveform="triangle")

# BLIT -- configurable harmonics
blit = synthesis.blit_saw(frames=48000, freq=220.0, harmonics=20)
blit_sq = synthesis.blit_square(frames=48000, freq=220.0)

# DPW -- differentiated parabolic wave
dpw = synthesis.dpw_saw(frames=48000, freq=440.0)
pulse = synthesis.dpw_pulse(frames=48000, freq=440.0, duty=0.3)

# MinBLEP -- highest antialiasing quality
mb = synthesis.minblep(frames=48000, freq=440.0, waveform="saw")
mb_sq = synthesis.minblep(frames=48000, freq=440.0, waveform="square", pulse_width=0.3)

Noise generators

noise = synthesis.white_noise(frames=48000, amp=0.5)
clocked = synthesis.clocked_noise(frames=48000, freq=1000.0)    # sample-and-hold
impulses = synthesis.dust(frames=48000, density=100.0)           # sparse Poisson impulses

Drum synthesis

Physically-inspired analog drum models from DaisySP:

# Analog models
kick = synthesis.analog_bass_drum(frames=48000, freq=60.0, decay=0.5, accent=0.8)
snare = synthesis.analog_snare_drum(frames=48000, freq=200.0, snappy=0.7, decay=0.4)
hat = synthesis.hihat(frames=48000, freq=3000.0, decay=0.3, noisiness=0.8)

# Synthesis-focused variants with extra controls
syn_kick = synthesis.synthetic_bass_drum(
    frames=48000, freq=60.0, dirtiness=0.3, fm_env_amount=0.5
)
syn_snare = synthesis.synthetic_snare_drum(
    frames=48000, freq=200.0, fm_amount=0.3
)

Physical modeling

from nanodsp.buffer import AudioBuffer

# Karplus-Strong plucked string
excitation = AudioBuffer.noise(frames=48000, seed=42)
plucked = synthesis.karplus_strong(excitation, freq_hz=440.0, brightness=0.5, damping=0.3)

# Simple pluck
p = synthesis.pluck(frames=48000, freq=440.0, decay=0.95, damp=0.9)

# Modal voice (resonant body excited by impulse)
modal = synthesis.modal_voice(frames=48000, freq=440.0, structure=0.5, brightness=0.6)

# Bowed string
bowed = synthesis.string_voice(frames=48000, freq=220.0, brightness=0.6)

# Water drop
drop = synthesis.drip(frames=48000, dettack=0.01)

STK instruments

Physical modeling instruments from the Synthesis ToolKit. Available: clarinet, flute, brass, bowed, plucked, sitar, stifkarp, saxofony, recorder, blowbotl, blowhole, whistle.

# Single note
clarinet = synthesis.synth_note("clarinet", freq=440.0, duration=1.0, velocity=0.8)
flute = synthesis.synth_note("flute", freq=880.0, duration=0.5)

# Sequence of notes
melody = synthesis.synth_sequence("flute", notes=[
    (440.0, 0.0, 0.5),       # (freq_hz, start_time_sec, duration_sec)
    (554.37, 0.5, 0.5),
    (659.26, 1.0, 1.0),
])