# Soft low impact

A low body and soft contact mark a title or chapter opening.

Source checkpoint: 8dc3dd143f8eb56223e62d40c694689330a94853. Original procedural synthesis by Renaissance Solutions with Codex.
Local review candidate: public distribution and reuse terms have not yet been selected.
Numbered audio, source and presets are preserved unchanged. Listening preferences and use under narration remain pending.

## Make it with your AI assistant

Ask whether your assistant can run Python and return WAV files. Give it this complete folder (or upload this ZIP and ask it to extract the files).
No account keys or Python packages are needed by the recipe. Use the supplied generator to reproduce our takes.
A prompt alone can lead to a different implementation.

Make an original soft low impact for a podcast chapter opening.
Imagine a close, rounded thump with a short, soft attack and a low body
that falls away. Keep it dry, without a cinematic boom or room reverb.
Use a 1.5-second file with the hit at 0.06 seconds and a one-second body.
Start the settling body frequency at 80 Hz.

Use Python's standard library and original synthesis only. Save separate
layers, a 48 kHz / 24-bit stereo master, a mono fold-down, and a 16-bit
stereo WAV preview. Leave 6 dB of sample-peak headroom. Save the source,
a JSON preset with a fixed seed, a manifest, and SHA-256 checksums.

If you can run the code, render and verify the files. Otherwise return
complete code and local commands, and say what remains unexecuted.
Preserve the first take as v001 so a later experiment cannot overwrite it.

## Run locally

Unzip the complete kit and open Terminal in the folder containing this README, effects/, scripts/ and library/.
Python 3.10 or later is required; reference bytes were generated with Python 3.14.3 on macOS.
Run the following commands from that folder. Use a fresh output folder for every attempt; existing takes will not be overwritten.

python3 effects/006-soft-impact/src/render.py --preset effects/006-soft-impact/presets/v001.json --output tmp/006-soft-impact-v001

python3 effects/006-soft-impact/src/render.py --preset effects/006-soft-impact/presets/v002.json --output tmp/006-soft-impact-v002

Open each new preview.wav in an audio player. stereo.wav is the 48 kHz/24-bit master, mono.wav is its mono fold-down, and stems/ contains aligned layers.
Check the retained files and reproduce all WAVs with:

python3 scripts/verify_library.py --reproduce

Byte equality is verified in the recorded runtime; check other runtimes. This command does not judge how a sound feels.

## What we did

1. Start a low tone with a brief pitch fall.
2. Add a softened noise attack.
3. Leave a quiet tail for editing.

## Change one thing

Keep v001 unchanged. Copy its preset to v002 and change only
impact_hz from 80 to 120, plus the take label. Keep the seed, timing,
body and attack gains, stereo width, duration, and -6 dBFS peak target.
Render both stems and the full mix. Measure the levels, explain any
normalization side effect, and leave the listening preference open.

Use the supplied source for these parameter names. With newly written code, first identify the equivalent control.
The body setting rises from 80 to 120 Hz. Timing stays fixed. Whether it carries better on small speakers still needs listening.
Both mixes share a sample-peak target; that does not mean they seem equally loud.

## Listen and decide

Which take reads clearly on ordinary speakers without overwhelming the voice?
Place the impact at a chapter title. Bring its level up from quiet until the emphasis is clear. Compare both takes and the passage without the effect.
Record what you heard, your preference (including neither or undecided), and one next change.
Technical checks passed for the reference files; human listening and use in context remain pending.

## Source identity

The original chapter SHA-256 is aa4668a5a98a40bfdf0641ad1eb812561ffb46b1cc820c5b61c02fc2d4610e9a.
Each library manifest records source, preset, dependencies and WAV hashes.
The included catalog is the matching single-recipe subset of the pinned Studio catalog.