hyperframes-audio

The saved excerpt is a snapshot from when this skill was listed. The external source remains the complete and most current version.

---
name: hyperframes-audio
description: >
  Use when audio already placed in a HyperFrames composition needs to be mixed:
  fade-in/fade-out, crossfade, track gain or volume, volume automation, ducking,
  a music bed that fights a voiceover (voiceover carve), effects on a track
  (EQ, compressor, limiter, gate, saturation, delay, reverb, chorus, phaser,
  bitcrush), automation envelopes drawn on a track's volume or any effect
  parameter, or one submix bus carrying a chain, a fader and an automation clock
  for several tracks at once (`<hf-audio-group>`).
  Don't use for sourcing or generating audio — finding BGM, SFX, or making a
  voiceover is `/media-use`. Don't use for clip timing or track layout, which is
  `/hyperframes-core`.
---

# HyperFrames Audio

A mix is a set of relationships, not a stack of processors. Two tracks that each
sound right alone can be unlistenable together, and the fix is almost never "turn
one down" — it is finding what they are fighting over and giving it to whichever
one needs it. Every tool here exists to express one of those relationships.

Effects live on the element as `data-fx-chain`, and preview and render run the
same Web Audio graph — the studio in a live context, the engine in an offline one
inside the browser it already drives. There is one implementation of each effect,
so what you hear while scrubbing is what gets written. You never tune twice.

Clip timing remains `/hyperframes-core`: audio/video trims and source ranges use
`data-start`, `data-duration`, and `data-media-start`, and crossfades overlap
clips on different tracks. This skill owns placed-track fade-in/fade-out,
crossfade envelopes, track gain/track volume, volume and effect automation,
ducking/voiceover carve, and the effect chain. `/media-use` owns sourcing,
generation, and preprocessing.

Constant `data-playback-rate` (`0.1..5`) is render-safe for picture and
pitch-preserved sound when matching audio/video elements use the same timing,
source offset, and rate. Source speed ramps are not supported because there is
no rate envelope; preprocess a derived synchronized asset. HyperFrames does not
provide automatic waveform sync or drift correction.
For copyable cut/crossfade/retime recipes, use `/hyperframes-core` → `references/creator-editing-recipes.md`.

Three attributes carry everything, on the audio/video element itself — or, for
the first two, on an `<hf-audio-group>` bus (see "One bus for many tracks"):

| Attribute         | Holds                                                     |
| ----------------- | --------------------------------------------------------- |
| `data-fx-chain`   | the effects, in signal order                              |
| `data-automation` | envelopes on this track's volume or its effect parameters |
| `data-fx-carve`   | the carve's own settings, so it can be re-derived         |

The shipped effect families are gain, EQ (highpass, lowpass, peaking, shelves),
compressor, limiter, gate, saturate, delay, reverb, chorus, phaser, and bitcrush.

Exact JSON for each, and the rules a lane must satisfy: `references/attributes.md`.
Every effect with its parameters, ranges and units: `references/fx-registry.md`.
How to work out what is wrong with a file you cannot hear:
`references/diagnosis.md`.
**Presets, named jobs and one-knob profiles, plus a symptom-to-fix table:
`references/presets.md`** — read that before hand-building a chain, because one
of the presets or named jobs usually already names the problem.

## How it fits together

Two authoring surfaces write those attributes; two runtimes read them through the
same builders. That shared middle is why preview predicts the render.

```mermaid
flowchart TB
  voice["voice track<br/>media file"]
  bed["music bed<br/>media file"]

  subgraph AUTHOR["Authoring — the only things that write attributes"]
    panel["Studio<br/>Voiceover carve control"]
    script["scripts/carve.mjs<br/>detects the pair, dynamic by default"]
    analysis["core/audioCarve.t