# Sound and Haptics

## Purpose

Non-visual feedback.

## Decisions

### Sound

- **Default:** on by default, **quiet**, for important events only.
- **Events that make a sound:** the minimal set, **errors and notifications** only. No sounds for success, sending, toggles, taps or delete.
- **Meaning:** a rising pitch means success or something positive, a falling pitch means an error or something negative, a notification is a single higher note, and toggles step up (on) or down (off) if they ever get sounds.
- **Loudness:** about 20% of full peak.
- **Rules:** follow the device's mute or silent switch; one master on/off setting in the app; sounds never play on page load and never on hover; separate toggles per category (notifications, confirmations, interface).
- **Character:** a soft, rounded "pop" that sits **25% of the way from a pure sine to a soft pop**, made **33% faster** than the first version and **pitched up about 6%** (one semitone). Each note dips about 11% in pitch as it plays, which gives the "pop". All sounds are at about 20% of peak:
  - **Success** (rising pair, about 419 Hz then 557 Hz)
  - **Error** (falling and lower, about 352 Hz then 281 Hz)
  - **Notification** (a single higher note, about 696 Hz)
- Only errors and notifications are played by default; the success sound is kept for if that set widens.

### Haptics (mobile)

- **Default:** follow the device's haptic setting, with an in-app toggle to turn them off.
- **Which interactions vibrate:** the minimal set: errors and warnings, success or confirmation, and the long-press menu opening.
- **Patterns:** the platform's built-in feedback types (light, medium and heavy impact, success, warning, error), so they feel native on each device.