v0.36.0: Banjo, mandolin, ukulele, cajón, vocal synth, granular

34 synth waveforms, 26 songs, vocal/formant synthesis with choir
preset, granular engine, banjo/mandolin/ukulele physical models,
cajón drum with 3 patterns, strum sweep on fretboard instruments.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

CHANGELOG.md

@@ -2,6 +2,25 @@
 
 All notable changes to PyTheory are documented here.
 
+## 0.36.0
+
+- **Banjo synth** — steel strings on drum-head body, nasal twang,
+  fast decay with membrane resonance
+- **Mandolin synth** — paired steel strings (natural chorus from
+  doubled courses), bright body resonance
+- **Ukulele synth** — nylon strings, small mid-heavy body, shorter
+  sustain than guitar
+- **Cajón drums** — bass (woody box thump), slap (snare wire buzz),
+  tap (ghost note). 3 patterns: cajon, cajon rumba, cajon folk
+- **Vocal/formant synth** — LF glottal model, 5 Peterson & Barney
+  formant peaks, jitter/shimmer, consonant onsets, per-note lyrics.
+  Presets: vocal, choir
+- **Granular synthesis** — grain cloud engine with scatter, pitch
+  variation, Hanning windows. Presets: granular_pad, granular_texture
+- **Strum sweep** — subtle grace notes before chord hit for natural
+  strum feel on all fretboard instruments
+- Mandola preset, 34 synth waveforms, 26 songs
+
 ## 0.35.0
 
 - **8.5x faster import** — dropped pytuning/sympy, lazy-load scipy.

docs/index.rst

@@ -77,7 +77,7 @@ What's Inside
   numbers), scale recommendation, modulation, voice leading
 - **Sequencing** — Score, Parts, arpeggiator, legato/glide, velocity,
   swing, humanize, tempo changes, song sections with repeat
-- **Synthesis** — 30 waveforms (including Karplus-Strong pluck, Hammond organ,
+- **Synthesis** — 34 waveforms (including Karplus-Strong pluck, Hammond organ,
   bowed string, and 14 dedicated instrument synths), 10 envelopes, 40+
   instrument presets, configurable FM, sub-oscillator, noise layer, filter
   envelope, velocity-to-brightness, analog oscillator drift, detune, stereo

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "pytheory"
-version = "0.35.1"
+version = "0.36.0"
 description = "Music Theory for Humans"
 readme = "README.md"
 license = "MIT"

pytheory/__init__.py

@@ -1,6 +1,6 @@
 """PyTheory: Music Theory for Humans."""
 
-__version__ = "0.35.1"
+__version__ = "0.36.0"
 
 from .tones import Tone, Interval
 from .systems import System, SYSTEMS, TET

pytheory/play.py

@@ -1130,6 +1130,48 @@ def granular_wave(hz, peak=SAMPLE_PEAK, n_samples=SAMPLE_RATE,
     return (peak * out).astype(numpy.int16)
 
 
+def banjo_wave(hz, peak=SAMPLE_PEAK, n_samples=SAMPLE_RATE):
+    """Banjo — steel strings on a drum-head body.
+
+    The banjo's distinctive twang comes from the membrane head
+    (like a drum skin) instead of a wooden soundboard. This gives
+    a sharp attack, bright tone, and fast decay with a nasal,
+    metallic quality. The 5th string drone adds shimmer.
+    """
+    period = int(SAMPLE_RATE / hz)
+    if period < 2:
+        period = 2
+    rng = numpy.random.default_rng(int(hz * 100) % 2**31)
+
+    # Steel string — bright, sharp attack
+    buf = rng.uniform(-0.9, 0.9, period).astype(numpy.float64)
+    # Minimal filtering — banjo keeps the brightness
+    for k in range(period - 1):
+        buf[k] = 0.7 * buf[k] + 0.3 * buf[k + 1]
+
+    out = numpy.zeros(n_samples, dtype=numpy.float64)
+    for i in range(n_samples):
+        out[i] = buf[i % period]
+        next_idx = (i + 1) % period
+        # Moderate decay — drum head rings but shorter than guitar
+        buf[i % period] = 0.5 * (buf[i % period] + buf[next_idx]) * 0.9988
+
+    # Drum-head resonance — nasal, ringy, mid-frequency peaks
+    # The membrane head rings more than wood — that's the twang
+    import scipy.signal as _sig
+    for center, bw, gain in [(600, 200, 0.5), (1500, 300, 0.4), (3000, 500, 0.25)]:
+        lo = max(20, center - bw)
+        hi = min(SAMPLE_RATE // 2 - 1, center + bw)
+        if lo < hi:
+            bp, ap = _sig.butter(2, [lo, hi], btype='band', fs=SAMPLE_RATE)
+            out += _sig.lfilter(bp, ap, out) * gain
+
+    mx = numpy.abs(out).max()
+    if mx > 0:
+        out /= mx
+    return (peak * out).astype(numpy.int16)
+
+
 def mandolin_wave(hz, peak=SAMPLE_PEAK, n_samples=SAMPLE_RATE):
     """Mandolin — paired steel strings, bright and ringing.
 
@@ -1523,6 +1565,7 @@ class Synth(Enum):
     SAXOPHONE = "saxophone_synth"
     GRANULAR = "granular_synth"
     VOCAL = "vocal_synth"
+    BANJO = "banjo_synth"
     MANDOLIN = "mandolin_synth"
     UKULELE = "ukulele_synth"
     ACOUSTIC_GUITAR = "acoustic_guitar_synth"
@@ -1548,7 +1591,8 @@ _SYNTH_FUNCTIONS = {
     "harp_synth": harp_wave, "upright_bass_synth": upright_bass_wave,
     "timpani_synth": timpani_wave, "saxophone_synth": saxophone_wave,
     "granular_synth": granular_wave, "vocal_synth": vocal_wave,
-    "mandolin_synth": mandolin_wave, "ukulele_synth": ukulele_wave,
+    "banjo_synth": banjo_wave, "mandolin_synth": mandolin_wave,
+    "ukulele_synth": ukulele_wave,
     "acoustic_guitar_synth": acoustic_guitar_wave,
     "sitar_synth": sitar_wave, "electric_guitar_synth": electric_guitar_wave,
 }

pytheory/rhythm.py

@@ -195,6 +195,10 @@ INSTRUMENTS = {
         "detune": 12, "lowpass": 3000, "lowpass_q": 1.5,
         "humanize": 0.2,
     },
+    "banjo": {
+        "synth": "banjo_synth", "envelope": "none",
+        "humanize": 0.2,
+    },
     "mandolin": {
         "synth": "mandolin_synth", "envelope": "none",
         "humanize": 0.2,

uv.lock

@@ -698,7 +698,7 @@ wheels = [
 
 [[package]]
 name = "pytheory"
-version = "0.35.1"
+version = "0.36.0"
 source = { editable = "." }
 dependencies = [
     { name = "numeral" },