Recommended Relevantly Related Resources

studyingsound.org — a long-running hub from Karen Collins (Carleton University; formerly U. of Waterloo) for the academic study of sound, listening, and audio culture; useful when the question shifts from how a sound is made to how it is received.

Best read alongside Sonic’s Chapter 4 (sound authoring & casting) and Chapter 9 (3D sound & auralization).

PhET (University of Colorado Boulder) — an award-winning collection of HTML5 physics simulations, designed for classroom use and built around clean parameter sliders and live visualizations. The same library is also distributed as an iPad app (see PhET Simulations on the iOS Apps page). Six PhET sims sit squarely alongside Sonic chapters 1–5:

• Sound Waves — visualize air-pressure variation as a sound wave propagates from a speaker, including two-source interference patterns. Pairs with Sonic Fig. 1.11 (molecule-wave visualizer).
• Waves Intro — introduce wave phenomena across water, sound, and light with shared amplitude and frequency controls. A gentle on-ramp before tackling the spectrum demos in chapter 3.
• Wave Interference — 2-D wave tanks (water, sound, light) with adjustable slit count and spacing. Complements chapter 5’s polar-pattern sandbox by showing why directional pickup arises from interference.
• Wave on a String — pulses and standing waves on a string, with adjustable tension and damping; reflection from fixed vs. free vs. open ends. The cleanest demonstration anywhere of the boundary conditions invoked in Sonic Fig. 3.3.
• Magnets & Electromagnets — bar magnets, electromagnets, current direction, and field visualization. The physical basis of dynamic microphones and moving-coil loudspeakers in chapter 5.
• Faraday’s Electromagnetic Lab — the induction half of the transducer story: move a bar magnet through a coil and watch the induced voltage. Same physics as a dynamic mic capsule.

falstad.com — Paul Falstad’s long-running collection of physics and signal-processing applets. Spartan UIs, fast feedback, and deep parameter access. The Fourier and digital-filter applets are particularly load-bearing for Sonic readers:

• Fourier series — drag the harmonic-amplitude bars and watch (and hear) the resulting waveform rebuild in real-time. Pairs with Sonic Figs. 3.1 (additive synthesis) and 3.2 (harmonic series).
• Ripple Tank — 2-D wave propagation in a tank with adjustable sources, walls, slits, and lenses. The classic complement to the PhET wave-interference sim.
• Vibrating Membrane — circular and rectangular drumhead normal modes; useful for understanding why percussion has inharmonic spectra unlike the strings of chapter 3.
• Coupled Oscillators — a ring of coupled masses showing dispersion and normal modes; intuition for why filters have a phase response, not just amplitude.
• Sound Interference — two speakers in a virtual room with adjustable position and frequency; constructive and destructive lobes mapped on a colormap. The cleanest demonstration of why microphone placement matters.
• Loaded String — a string of beads (discrete masses on a string) and its normal modes; the bridge from physical strings to the discrete-time signal processing of chapter 6.
• Digital Filter — drag poles and zeros on the unit circle and watch the magnitude and phase response update live. The natural follow-on to Sonic’s graphic-EQ and filter demos in chapter 7.
• 1-D Wave Box — the wave equation on a 1-D string with adjustable boundary conditions and damping; trace incident, reflected, and standing components separately.
• 2-D Wave Equation — the wave equation on a 2-D rectangular grid. Fires pulses, sets sources, and shows dispersion and diffraction patterns evolving.
• Mode Box — standing-wave modes inside a rectangular cavity (room modes). Useful complement to Sonic’s reverb discussion in chapter 7.
• Bar Waves — transverse and longitudinal modes on a free or clamped bar (xylophone-bar physics). Inharmonic spectra made visible.
• Vowel Synthesizer — drag two formant frequencies (F₁, F₂) around the vowel-space chart and hear the synthesized vowel. The classic source-filter model of speech, made interactive.

exploresound.org — the Acoustical Society of America’s public-outreach hub: classroom-tested demos, lesson plans, and browser-based tools spanning acoustics, hearing, and audio engineering. Two collections are particularly load-bearing for Sonic readers:

• Acoustic Simulators — a curated catalog of interactive acoustic simulators (room acoustics, source directivity, sound propagation, wave behavior). Complementary to the wave-on-a-string and ripple-tank sims listed above; many target the room-and-reverb material in chapter 7.
• Spectrogram Lab — in-browser real-time spectrogram from the device microphone, with tunable time/frequency resolution. Pairs naturally with the time-frequency material in chapter 3 and the spectrogram-3D demo in chapter 7.

HyperPhysics · Sound concepts — Carl Rod Nave’s HyperPhysics at Georgia State University, hub page for sound. A node-and-arrow concept map covering acoustics, hearing, musical instruments, room acoustics, and ultrasound — each node a brief illustrated explainer with cross-links.

Useful as a second opinion on any topic in Sonic’s Chapter 1–3. The visual organization is a teaching aid in itself.

Four long-standing teaching sites that go deep on the physical and musical side of acoustics, all maintained by university physicists with decades of pedagogical credit:

• UNSW Music Acoustics (Joe Wolfe, University of New South Wales) — a comprehensive resource on the acoustics of musical instruments, the singing voice, and the physics of music. Pages on flutes, brass, strings, and the human vocal tract include actual measured impedance curves.
• UNSW Physics Animations (Joe Wolfe & colleagues) — companion to the above: short video animations of waves, oscillators, and resonance, narrated for first-year physics students.
• Acoustics & Vibration Animations (Dan Russell, Penn State) — the classic collection of animated explainers: longitudinal vs. transverse waves, Doppler effect, beats, room modes, polar patterns, and dozens more. Many of the original GIFs have been refreshed to modern HTML5.
• Why You Hear What You Hear (Eric J. Heller) — companion site to Heller’s Princeton University Press textbook of the same name, an experimental and graphics-rich treatment of sound, music, and psychoacoustics.
• Edly’s Piano Basics (Ed Roseman) — an accessible primer on the layout of the piano keyboard, reading music, and basic music theory, from the long-running Edly’s Music Theory for Practical People series. Useful background for readers without prior keyboard experience who want to make sense of Sonic’s pitch-class wheels, harmonic-series diagrams, and Shepard scales.
• Wolfram Demonstrations Project — a large library of interactive Mathematica-based demos. Several are directly relevant to Sonic:
  • Pythagorean, Meantone & Equal Temperament Musical Scales — interactive comparison of the three historically dominant tuning systems. Hear the same scale tuned three ways; see why Sonic’s Fig. 3.3 harmonic seventh is 31 cents flat of its equal-tempered neighbor.
  • Exploring Musical Tuning and Temperament — a broader survey of tuning systems beyond the canonical three, including just intonation and various well-tempered schemes.
  • Chords in Equal Temperament and Just Intonation — listen to common chord qualities (major, minor, dominant 7^th) in both tunings and hear the beating differences directly.
  • Musical Lines and Curves — visualization of melodic contour as pitch-vs-time geometry; a useful bridge between the time-domain signal view and a musical phrase.
  • Network of Musical Instruments for Rhythm Accompaniment — generative rhythm patterns laid over a network of percussion instruments.
  • Topic index pages where many more related demos live: Audio · Music theory · School music.

The primary sources that this field grew out of. Public-domain classics of acoustics and psychoacoustics, presented here as modern reading editions where good ones exist, with a stable archival scan as a backstop against link rot.

• On the Sensations of Tone (Hermann von Helmholtz, 1863; English translation by Alexander J. Ellis) — the foundational treatise of modern psychoacoustics and the physical theory of music. Helmholtz’s account of timbre as harmonic spectrum, of beats and roughness as the basis of consonance and dissonance, and of combination tones underlies much of what Sonic demonstrates interactively — see the harmonic-series diagrams in Chapter 3 and the beat-frequency material. SensationsOfTone.com is a clean, chapter-navigable modern web edition of the full Ellis translation; if it is ever unreachable, the canonical scanned original is mirrored at the Internet Archive.

A short tour of the best free, browser-based, hands-on audio playgrounds. All run directly in the browser — no downloads, no plugins. Particularly suitable for classroom use. Most of the Google entries below are sub-pages of Chrome Music Lab — Experiments, the umbrella index where the full collection lives; if a specific link below ever goes stale, the umbrella index will still have it.

Rhythm & sequencing

• Chrome Music Lab — Song Maker — Google’s iconic, colorful grid sequencer. Sketch melodies and drum beats with immediate visual and audio feedback; shareable via URL.
• The Infinite Drum Machine (Google AI Experiment) — thousands of everyday sound samples mapped into a 2-D similarity space via t-SNE; pick percussive sounds by their timbre rather than their name and sequence them into patterns.
• Drumbit — accessible online drum machine with preset kits and adjustable step sequencers for building quick rhythms.
• EM Pedagogy — Free Rhythm Sequencers — an annotated guide to free in-browser rhythm sequencers, written from a music-education perspective. A good companion read after poking at the sequencers above, for how they compare.
• Chrome Music Lab — Rhythm — tap to choose which beats animal characters play; tempo, meter (2 / 3 / 4 / 6) and ostinato pattern are all editable, with the resulting groove drawn as a circular pulse diagram. The shortest path to feeling polyrhythm.
• Rhythm Circle (Paul Lascabettes) — interactive rhythm-training exercises focused on the time-domain side of music (meter, subdivision, polyrhythm). A natural complement to Sonic’s frequency-and-spectrum focus — what the time axis is to the spectrum axis, rhythm is to pitch.

Sound & audio visualization

• Chrome Music Lab — Spectrogram — interactive live spectrogram of the microphone or built-in sources; the simplest demo anywhere of how different timbres appear visually.
• Chrome Music Lab — Sound Waves — pure visual demo of how air molecules compress and rarefy to carry a sound. Directly analogous to (and complements) Sonic’s own Fig. 1.11 molecule-wave visualizer.
• Chrome Music Lab — Voice Spinner — record a short vocal phrase, then spin a turntable to play it back at any pitch / speed: forward, reverse, fast, slow. Hands-on demonstration of the linkage between sample rate, pitch, and the chipmunk / Darth-Vader effects discussed in chapter 6.

Music creation & melody

• Google Magenta — Web Demos — a collection of machine-learning music tools (Melody Mixer, Beat Blender, Latent Loops, NSynth Super, …) for interpolating between loops, melodies, and instrument timbres in a learned latent space.
• Chrome Music Lab — Kandinsky — an interactive painting experiment where shapes and lines are algorithmically translated into musical phrases. Named for the Kandinsky synaesthesia tradition.
• Chrome Music Lab — Chords — click or tap any white key on a one-octave piano and the experiment plays the matching major and minor triads on top, with the chord notes highlighted on the keyboard. The shortest hands-on path from individual pitches to harmonic function.
• Audiotool — modular browser-based DAW — already listed under “Free audio tools” below.
• BandLab — a free cloud-based DAW and musician social network: multi-track recording in the browser, virtual instruments and effects, a sizeable library of royalty-free loops and samples, and built-in collaboration so a project can be passed between phone, tablet, desktop, and other collaborators. Closer in spirit to GarageBand or Logic than to Audiotool’s patcher metaphor.
• Playtronica Synth — a free, immediate browser synth: oscillator + filter + envelope + delay/reverb effects, plus a step sequencer, all on one screen. Built for fast sound design without account creation or download. A useful zero-friction sketchpad for trying the synthesis ideas in chapter 3.

Collaborative sound

• Plink — chaotic multiplayer music experience: a shared browser-based grid where strangers from anywhere on the internet make music together in real-time. Sonic’s narrowcasting controls (mute / solo per voice) have a direct analog here in the “mute other players” affordance.
• Chrome Music Lab — Shared Piano — a browser piano with shareable rooms: each room gets a URL, anyone who opens it plays the same keyboard in real time. More structured than Plink’s grid — the participants share an actual keyboard layout, so duets and call-and-response work as intended. Good for classroom “everyone open this URL” sessions.

Developer references

• alemangui/web-audio-resources — a community-curated index of Web Audio API libraries, articles, demos, and tools (Alejandro Mantovani, GitHub). For building something like the demos here, this is a good first stop.
• WebAudio TinySynth — SoundEdit (Yutaka Hayashi / g200kg) — an in-browser editor for the 128 GM-instrument presets that drive Hayashi’s tiny General-MIDI synthesizer. Each preset is a small JSON of oscillator/envelope/filter parameters; the editor allows the numbers to be tweaked and the result auditioned on a virtual keyboard. The whole engine is ~30 KB of pure Web Audio with no samples, so it’s also a compact tutorial in how a software GM synth is structured.

Four pieces of free software a reader of Sonic might find useful — on their machine, or in another browser tab:

• Audacity — the canonical cross-platform open-source audio editor: record, edit, apply effects, and analyze waveforms and spectra. Sonic’s discussion of editing, levels, and quantization in chapter 6 can be reproduced almost button-for-button in Audacity.
• Pure Data (Pd, Miller Puckette) — an open-source real-time visual programming language for audio synthesis and analysis. The patcher metaphor (boxes wired together) is the same one used in Max/MSP. Excellent for hands-on exploration of every signal-processing concept in chapters 3 and 7.
• Audiotool — a free browser-based music-production studio. Modular synthesizers, drum machines, samplers, and effects wired together on a patchable canvas; the resulting track plays live and can be saved and shared with a community. The closest thing to having a full DAW open in the next tab while reading Sonic chapters 3 and 7.
• SoundHack (Tom Erbe) — the original “phase vocoder for the people.” A free Mac application for spectral and convolution-based sound processing: time-stretching and pitch-shifting independent of one another, FFT mutation, and convolution reverb with arbitrary impulse responses. Cited inline on Sonic’s Shepard Tones page and now listed here for direct download.

• Audio & Sound Basics (Joe Albano, ask.Video) — well-paced introductory video course covering many of the same fundamentals Sonic does in chapters 1–3 — waveforms, frequency & pitch, level & loudness, harmonics & timbre. Formerly distributed as the iOS “Audio Concepts” app series, now available only as a streamable video series on ask.Video.

suddenhearingloss.support — a patient-and-clinician community resource on sudden sensorineural hearing loss (SSNHL): symptom checklists, treatment timelines, lived-experience essays, and links to peer-reviewed clinical guidance. Founded by Carly Sygrove after her own SSNHL diagnosis; the site is the canonical companion to the book Sudden Hearing Loss: Stories of Hope, Guidance, and Support (Sygrove, Simonson, & Norman, 2025) listed in the bibliography.

Best read alongside Sonic’s Chapter 2 (intensity, loudness & the equal-loudness contours): the chapter explains how the auditory system encodes level across frequency; this site documents what happens when that encoding breaks abruptly, and what to do in the first 24–72 hours (a medical emergency window most readers do not realize they are inside).