Ableton Learning Synths: Modulating amplitude with envelopes

Source snapshot

Vendored from Ableton's amplitude-envelope lesson at learningsynths.ableton.com/en/envelopes/modulating-amplitude-with-envelopes. The local route keeps the published lesson shell and ADSR runtime from shared scripts so the press-and-hold envelope scene boots from local assets.

• The archive preserves the published envelope scenes instead of rebuilding them in a custom synth teaching page.
• The ADSR shape scene is treated as parity-critical because it is the clearest demonstration in the lesson.

Asset handoff

• shared/ableton-learning-synths-musiclab.js plus shared/ableton-learning-synths-archive.js drive the lesson shell and ADSR runtime.
• Route-local inventory matches the rest of the shipped Learning Synths batch: shared fonts, text payloads, RNBO patch data, and lesson WAVs.
• Assets such as content/lessons/en/synthesis/sustain-clarinet.wav and rnbo/patches/learning-synth.json stay on relative paths for subpath hosting.

Known deviations

• A shared footer carries the single original-page reference link; the upstream lesson shell is stripped from the public body.
• Ableton feedback, privacy, language-switch, analytics, and cookie surfaces are removed from the public route.
• Local chapter links are rewritten after mount so the shipped synth family stays internally navigable.

Validation guidance

• node tools/check-public-surface.mjs . keeps the public route footer-only.
• node tools/smoke-bundle.mjs . --group music (or --route ableton-learning-synths-modulating-amplitude-with-envelopes) verifies local script loading, the ADSR envelope redraw, and the held-note path after parameter changes.
• Smoke asserts the expected local asset counts and keeps the no-remote-playable-media guard clean after lesson boot and interaction.