Sounds on the Web

Review UI code for audio feedback best practices and accessibility.

How It Works

1. Read the specified files (or prompt user for files/pattern)
2. Check against all rules below
3. Output findings in file:line format

Rule Categories

Priority	Category	Prefix
1	Accessibility	a11y-
2	Appropriateness	appropriate-
3	Implementation	impl-
4	Weight Matching	weight-

Rules

Accessibility Rules

a11y-visual-equivalent

Every audio cue must have a visual equivalent; sound never replaces visual feedback.

Fail:

function SubmitButton({ onClick }) {
  const handleClick = () => {
    playSound("success");
    onClick(); // No visual confirmation
  };
}

Pass:

function SubmitButton({ onClick }) {
  const [status, setStatus] = useState("idle");
  
  const handleClick = () => {
    playSound("success");
    setStatus("success"); // Visual feedback too
    onClick();
  };
  
  return <button data-status={status}>Submit</button>;
}

a11y-toggle-setting

Provide explicit toggle to disable sounds in settings.

Fail:

// No way to disable sounds
function App() {
  return <SoundProvider>{children}</SoundProvider>;
}

Pass:

function App() {
  const { soundEnabled } = usePreferences();
  return (
    <SoundProvider enabled={soundEnabled}>
      {children}
    </SoundProvider>
  );
}

a11y-reduced-motion-check

Respect prefers-reduced-motion as proxy for sound sensitivity.

Fail:

function playSound(name: string) {
  audio.play(); // Plays regardless of preferences
}

Pass:

function playSound(name: string) {
  const prefersReducedMotion = window.matchMedia(
    "(prefers-reduced-motion: reduce)"
  ).matches;
  
  if (prefersReducedMotion) return;
  audio.play();
}

a11y-volume-control

Allow volume adjustment independent of system volume.

Fail:

function playSound() {
  audio.volume = 1; // Always full volume
  audio.play();
}

Pass:

function playSound() {
  const { volume } = usePreferences();
  audio.volume = volume; // User-controlled
  audio.play();
}

Appropriateness Rules

appropriate-no-high-frequency

Do not add sound to high-frequency interactions (typing, keyboard navigation).

Fail:

function Input({ onChange }) {
  const handleChange = (e) => {
    playSound("keystroke"); // Annoying on every keystroke
    onChange(e);
  };
}

Pass:

function Input({ onChange }) {
  // No sound on typing - visual feedback only
  return <input onChange={onChange} />;
}

appropriate-confirmations-only

Sound is appropriate for confirmations: payments, uploads, form submissions.

Pass:

async function handlePayment() {
  await processPayment();
  playSound("success"); // Appropriate - significant action
  showConfirmation();
}

appropriate-errors-warnings

Sound is appropriate for errors and warnings that can't be overlooked.

Pass:

function handleError(error: Error) {
  playSound("error"); // Appropriate - needs attention
  showErrorToast(error.message);
}

appropriate-no-decorative

Do not add sound to decorative moments with no informational value.

Fail:

function Card({ onHover }) {
  return (
    <div onMouseEnter={() => playSound("hover")}> {/* Decorative, no value */}
      {children}
    </div>
  );
}

appropriate-no-punishing

Sound should inform, not punish; avoid harsh sounds for user mistakes.

Fail:

function ValidationError() {
  playSound("loud-buzzer"); // Punishing
  return <span>Invalid input</span>;
}

Pass:

function ValidationError() {
  playSound("gentle-alert"); // Informative but not harsh
  return <span>Invalid input</span>;
}

Implementation Rules

impl-preload-audio

Preload audio files to avoid playback delay.

Fail:

function playSound(name: string) {
  const audio = new Audio(`/sounds/${name}.mp3`); // Loads on demand
  audio.play();
}

Pass:

const sounds = {
  success: new Audio("/sounds/success.mp3"),
  error: new Audio("/sounds/error.mp3"),
};

// Preload on app init
Object.values(sounds).forEach(audio => audio.load());

function playSound(name: keyof typeof sounds) {
  sounds[name].currentTime = 0;
  sounds[name].play();
}

impl-default-subtle

Default volume should be subtle, not loud.

Fail:

const DEFAULT_VOLUME = 1.0; // Too loud

Pass:

const DEFAULT_VOLUME = 0.3; // Subtle default

impl-reset-current-time

Reset audio currentTime before replay to allow rapid triggering.

Fail:

function playSound() {
  audio.play(); // Won't replay if already playing
}

Pass:

function playSound() {
  audio.currentTime = 0;
  audio.play();
}

Weight Matching Rules

weight-match-action

Sound weight should match action importance.

Fail:

// Loud fanfare for minor action
function handleToggle() {
  playSound("triumphant-fanfare");
  setEnabled(!enabled);
}

Pass:

// Subtle click for minor action
function handleToggle() {
  playSound("soft-click");
  setEnabled(!enabled);
}

// Richer sound for significant action
function handlePurchase() {
  playSound("success-chime");
  completePurchase();
}

weight-duration-matches-action

Sound duration should match action duration.

Fail:

// 2-second sound for instant action
function handleClick() {
  playSound("long-whoosh"); // 2000ms
  // Action completes immediately
}

Pass:

// Short sound for instant action
function handleClick() {
  playSound("click"); // 50ms
}

// Longer sound for process
function handleUpload() {
  playSound("upload-progress"); // Matches upload duration
}

Output Format

When reviewing files, output findings as:

file:line - [rule-id] description of issue

Example:
components/input/index.tsx:23 - [appropriate-no-high-frequency] Playing sound on every keystroke
lib/sounds.ts:45 - [a11y-reduced-motion-check] Not checking prefers-reduced-motion

Summary Table

After findings, output a summary:

Rule	Count	Severity
a11y-visual-equivalent	2	HIGH
appropriate-no-high-frequency	1	HIGH
impl-preload-audio	3	MEDIUM

Sound Appropriateness Matrix

Interaction	Sound?	Reason
Payment success	Yes	Significant confirmation
Form submission	Yes	User needs assurance
Error state	Yes	Can't be overlooked
Notification	Yes	May not be looking at screen
Button click	Maybe	Only for significant buttons
Typing	No	Too frequent
Hover	No	Decorative only
Scroll	No	Too frequent
Navigation	No	Keyboard nav would be noisy

References

• Web Audio API Documentation
• prefers-reduced-motion