Pluckable Strings

Original Article ↗ Hacker News Discussion ↗

Musical design and why it sounds good

  • Strings are grouped into chords; default layout uses C, Am, F, G, a very common pop progression related to the ’50s progression.
  • Because all notes within a group form a chord and the chords fit well together, almost any random interaction sounds pleasant.
  • Users can switch to other chord sets (e.g., Andalusian) via the note icon, which changes the mood while preserving harmonic coherence.

Physical modeling and sound behavior

  • The app claims to use a math-based string simulator: audio and visuals are driven by the same model, no samples.
  • Each string is modeled with 12 harmonic overtones; amplitudes come from a Fourier transform of the plucked shape at release, with higher harmonics decaying faster.
  • Pluck position affects timbre: plucking near the center emphasizes different harmonics than near the ends, mirroring real instruments and pickup placement on guitars.
  • MIDI velocity is mapped to pluck position and pluck strength, giving brighter sound for stronger notes.

Implementation details and technical critiques

  • Audio is computed on the GPU in blocks (1024-sample buffers), with millions of calculations per second.
  • Many users report crackling/popping, especially in Chromium-based browsers; increasing buffer size helps some.
  • Several commenters attribute glitches to createScriptProcessor and argue it should be replaced with AudioWorklet plus WASM/SharedArrayBuffer for robust real-time audio.
  • Karplus–Strong synthesis is discussed as a related but simpler plucked-string method; some feel this demo sounds better and more physically grounded.

UX, platform issues, and discoverability

  • On iOS, the hardware mute switch can block sound even when volume is up, causing confusion; headphones may bypass this.
  • Some report no sound or degraded audio on certain browser/OS combinations (Firefox/Safari/iPad, Linux, Windows).
  • The help (“?”) and music buttons are easy to miss; once discovered, users enjoy preloaded classical/MIDI pieces, though some files 404 or expose timing weaknesses.
  • Drag-copy in the help overlay doesn’t work, frustrating users who wanted to share details.

Reception and potential uses

  • Overall reaction is strongly positive: “fun,” “lovely,” “stress-relief,” and “great for kids.”
  • Suggestions include adding string–string resonance, different materials (steel/nylon/gut), better audio backend, educational modes, games, and art installations.