summerengine/summer/audio-direction

/audio-direction — Define the Sonic Identity

Overview

Many indie games sound like one sound library used flat: the same generic "swoosh" for menu, jump, pickup and hit. This skill builds an audio bible that names the music style, the SFX vocabulary, the dynamic music plan, and the spatial / mix rules. Writes to .summer/audio-bible.md and configures the audio bus layout in the project so the rest of the work has a real foundation.

Core principle: SFX needs a vocabulary, not a library. Eight named SFX classes with consistent character beat 80 random library hits.

Steps

1. Open with three references

Ask exactly this:

Three reference tracks, games, or films for the music. What instruments matter? And what's the SFX vibe — chunky, clean, synthetic, or organic?

Three is the minimum. One or two collapses into a clone.

If they freeze, offer four axes (not titles):

Pick the closest: a) orchestral + cinematic (Hollow Knight, Journey), b) lo-fi electronic + ambient (Disco Elysium, Outer Wilds), c) chiptune / synth (Hyper Light Drifter, Celeste), d) acoustic / folk (Sable, A Short Hike).

2. Read the brief and art bible if they exist

Read .summer/GameSoul.md
Read .summer/art-bible.md

Audio must rhyme with the visuals. Quote it back:

Art bible says "soft, hand-warmed, golden-hour, painterly". That rhymes with acoustic / folk / lo-fi over orchestral or aggressive synth. Confirming.

If the brief says "horror", that constrains the music style harder than the user's references will. Name the constraint.

3. Pin the music style

Force one primary style. Sub-styles can blend, but a primary is required.

Ask:

One primary style. Which?

4. Define tempo + key range

Concrete numbers, not "varies".

Tempo range: 80–110 BPM (slow side; combat would push 120+)
Key center: D minor (warm but melancholic)
Modulation rule: combat tracks shift to D dorian, calm tracks to D natural minor
Time signature: 4/4 default; 6/8 for emotional cues

5. Build the SFX vocabulary

Eight named classes. Each class has a character, not a single sound.

Ask:

Eight classes above. Adjust any character / examples / DON'Ts?

6. Define the dynamic music plan

Static music = one track loops forever in a level. Boring. Dynamic music = layers swell with player state. Pick a model.

Pick one. State the state machine:

States:
  CALM        — exploration, low intensity
  TENSION     — enemies aware but not engaged
  COMBAT      — engaged
  VICTORY     — encounter cleared (4-second sting → return to CALM)
 
Transitions:
  CALM → TENSION   when an enemy detects the player (2s crossfade)
  TENSION → COMBAT when first damage exchanged (instant drum stem)
  COMBAT → VICTORY when last enemy dies (drum stem cuts, brass swell)
  VICTORY → CALM   after 4s
 
Rules:
  No state stays > 90s without variation (loop with bar-1 randomization)
  Volume ducking: dialogue active → music -6dB
  Boss music is its own track; ignores normal state machine

7. Define the spatial + mix rules

8. Configure the audio bus layout

Real audio in Summer Engine needs a bus layout. A new project starts with only the Master bus, so configure the remaining buses now.

Preferred (Summer MCP): Buses are typically in default_bus_layout.tres. Modify project setting:

summer_project_setting(key="audio/buses/default_bus_layout", value="res://audio/default_bus_layout.tres")

Ask the user:

May I create audio/default_bus_layout.tres with these buses: Master / Music / SFX / UI / Voice / Ambient / Reverb_Small / Reverb_Large / Reverb_Outdoor?

On yes, write the .tres directly via Write (it is the engine's plain-text resource format):

Write audio/default_bus_layout.tres

Fallback (no MCP): Print the .tres for the user to paste, plus the project.godot line.

9. Save the audio bible

Always write the bible. Path: .summer/audio-bible.md.

# Audio Bible — <Game Name>
 
**References:** <3 specific tracks / games / films>
**Style:** <one of the 8 above>
**Tempo / key:** 80–110 BPM, D minor, 4/4
 
## SFX Vocabulary
| Class | Character | Examples | DON'T |
|---|---|---|---|
| UI | Soft, woody, 60-100ms | hover, click | bell tones |
| Pickup positive | Warm major-third, 200-400ms | coin, heal | pure sine |
| ... | ... | ... | ... |
 
## Dynamic Music Plan
**Model:** Layered stems
**States:** CALM / TENSION / COMBAT / VICTORY
**Transitions:** ...
**Rules:** ...
 
## Spatial + Mix
-3D attenuation: inverse-square, 25m
-Reverb buses: small / large / outdoor
-HRTF: ON
-Master ceiling: -1 dBTP
-Mix bus: Music -8 dB, SFX 0 dB, UI -3 dB
-Footstep rolloff: 4m player / 10m NPC
 
## Bus Layout
Master → Music, SFX (→ Reverb_Small / Large / Outdoor), UI, Voice, Ambient

Ask:

May I create .summer/audio-bible.md with this bible?

10. Optional — generate first SFX seeds

If the user wants to start generating, propose 3-5 SFX seeds aligned with the vocabulary. These are starting points, not finals. Generate them with the sound-effect skill: the first sound effect in a chat starts with its question (three versions from three models, picked by ear in Summer Studio), and its prompt shape is the one that tested well.

assets.generate_audio({ capability: "sound_effects", text: "Foley one-shot: a fingertip taps a small wooden button, soft woody click, no tail, close-mic, dry, no reverb, no music, no voices.", durationSeconds: 0.5 })
assets.generate_audio({ capability: "sound_effects", text: "Foley one-shot: a small gold coin drops onto a wooden table, bright metallic ting with a short ring, close-mic, dry, no music, no voices.", durationSeconds: 0.5 })
assets.generate_audio({ capability: "sound_effects", text: "Foley one-shot: a fist hits a padded leather vest, low-mid thump, no tail, close-mic, dry, no reverb, no music, no voices.", durationSeconds: 0.5 })

capability is required; sound_effects reads from text (not prompt), and the length argument is durationSeconds (not duration) with a floor of 0.5 s (1 s for Stable Audio 3 SFX). Leave out modelId so the person's approved default model runs. Ask for the character you want inside the text and let the player only use the front of the clip — you cannot request 80 ms.

Ask first:

May I generate first-pass SFX seeds for UI, pickup, and damage classes? They're starting points, not finals.

11. Route to the next step

End with:

Bible saved. Next:

- /design-mechanic to wire SFX cues into specific mechanics.

- /game-feel if you haven't paired audio with visual effect cues yet.

- Author or generate the calm music track first; it's the longest-running and sets the room tone.

Common mistakes

Collaborative protocol

This skill writes one bible (.summer/audio-bible.md), creates a bus layout (audio/default_bus_layout.tres), modifies project.godot, and may generate audio (metered). Always ask before writing or generating. See summer_docs_read id reference/collaborative-protocol.

Want a working starter?

No template — this is a workflow that produces the bible the rest of the project obeys. After the bible exists, the bus layout is set up and any subsequent audio work (footstep system, dynamic music) reads from it.

See also