A lane with no =pattern produced different defaults on web vs device — a real,
shipped divergence the new conformance suite caught (e.g. hatClosed:4/2 in
"Four-on-the-floor" played steady 8ths in the browser but quarter-notes on the
device). Adopt one rule everywhere: every subdivision sounds at normal level,
accents fall ONLY on group starts (the grouping is the accent map).
- pico-cp/app.py, pico-explorer/app.py: off-beat subdivisions sound at normal (1)
instead of resting (0); group-start accenting was already correct.
- src/engine.js: default beatsOn accents group starts only (was: every beat);
laneCfgToStr isDefault check updated to match so round-trips stay idempotent.
- docs + fixtures: document the rule; default-pattern vectors now pass on both.
Audible effect (intended): device subdivided hat/ride lanes gain their off-beat
strokes (now match the web); web stops over-accenting every beat. Lanes with an
explicit =pattern are unchanged. Verified green via node tests/run.mjs.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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