Root cause: timeline play passes exactAudioTime as 4th param which
SpessaSynth interprets as enableReverh (boolean). All notes at T=0.
Fix: compute delay = startTime - ctx.currentTime, use setTimeout
to call noteOn(channel, pitch, vel) at correct future time.
Never pass startTime to noteOn() — SpessaSynth doesn't support it.
Per md/38_FLOWCLIENT.md analysis:
- Add _initPromise to serialize concurrent init calls (no duplicate worklet)
- audioContext.resume() before worklet.loadModule
- selectInstrument creates AudioContext + awaits init if not ready
- playNote tries SpessaSynth first, falls back to oscillator on error
- All MIDI commands wrapped in try/catch with oscillator fallback
- Add missing if (_initialized && _synthInstance) return to init()
- soundBank is main-thread proxy, worklet has actual presets
- Check selectablePresetList.length from soundBankManager (worklet state)
- Log when presets are empty (SpessaSynth parser issue)
Root cause: selectInstrument called before getAudioContext triggers init.
_initialized=false → selectInstrument returns immediately → no sound bank.
Fix: selectInstrument creates AudioContext + calls init() if not ready,
waits for completion before proceeding with bank/program routing.
Per md/38_FLOWCLIENT.md Phase 1: SpessaSynth output was not
connected to speakers. Add synth.connect(audioContext.destination)
after construction to route synthesized audio to user speakers.
Per md/38_FLOWCLIENT.md flow:
- _addBankWithTimeout: wraps SpessaSynth addSoundBank with Promise.race
- 15s timeout breaks deadlock when AudioWorklet parser fails silently
- Phase 3 (channel setup) only runs after Phase 2 (load) confirms success
- Falls back to oscillator when bank can't be loaded
- SpessaSynth bank loading fails in AudioWorklet for unknown reason
- Set _initialized=false after init so playNote uses oscillator path
- Server-side FluidSynth render produces authentic SoundFont audio on Export
- playNote logs warning when _currentSfId is null (no bank)
- _playNoteSpessa catches noteOn errors, falls back to _playNoteOsc
- Prevents 'No preset found' from breaking playback
- Add importmap in index.html to map spessasynth_core to CDN URL
- Load spessasynth_lib from CDN directly (with importmap resolving deps)
- WorkerSynthesizer fallback also uses CDN import
- Ensures library and processor use same spessasynth_core version
- Download spessasynth_processor.min.js from CDN, serve as static file
- Change __SpessaSynthCDN to /static/js/services/
- Fix version mismatch between esm.sh library and CDN processor
- Clone ArrayBuffer before sendToWorklet (transfer neuters original)
- Re-await synthInstance.isReady after addSoundBank
- Force controllerChange(0,0,0) + programChange(0,0) after load
- Add _initInProgress flag to prevent concurrent init calls
- Remove auto-loadSoundFont from init (confuses user when loading DSK)
- SF3 loading happens only when user selects an instrument
- _find_chunk starts at offset 12 (after RIFF header)
- Add _find_list_of_type to locate sdta LIST
- Update sdta LIST size after smpl data replacement
- Fix 'Invalid chunk header' error in SpessaSynth
- SGM_v2.01 too large (529MB WAV) falls back to SF2
- Frontend serialize: use undefined instead of null for synth_engine
- Backend validate: strip None synth_engine from tracks before schema validation
- Prevents 'None is not of type object' schema error
- jdelivr raw index.js has bare import 'spessasynth_core' which browser can't resolve
- esm.sh automatically rewrites bare imports to full URLs
- Keep jdelivr for worklet processor (self-contained, no imports)
- WorkerSynthesizer fallback also uses esm.sh
- Fix CDN URL: spessasynth_lib@4.3.1/dist/index.js (was @latest with wrong path)
- Use WorkletSynthesizer instead of Synthesizer (correct class name)
- Add audioWorklet.addModule() for processor CDN URL
- Await synth.isReady before use
- Use soundBankManager.addSoundBank() (correct API)
- Fallback to WorkerSynthesizer if AudioWorklet fails
- getAudioContext() calls SonicSF.init on every call (not just first)
- soundfontPlayer.init retries after 1s if SpessaSynth module not loaded yet
- Auto-loads sgm_v2.01 SF3 on successful init
- Fixes race condition: module script loads after regular scripts
- Remove small Synth button between ARM and Monitor (duplicate)
- Remove empty try/catch that swallowed all MIDI handler errors
- Ensure MIDI keyboard passes synth_engine context to playNote
- Direct fallback to armed main track when no PIANO_ROLL sub-tab armed
When MIDI note-on received and no PIANO_ROLL sub-tab is armed,
fallback to armed track in main session. Read its synth_engine and
instrumentProgram to route audio through correct instrument.
Route to track gainNode if available.
Add sfPresetSearchQuery state + search input in instrument selector
modal. Filters sfPresets by name (case-insensitive) when user types.
Clear search on SoundFont switch / modal close.
- toggleTrackDrum: sets is_percussion + soundfont_bank=128
- 🥁 button in track control panel (between Solo and Record)
- Shows 'D' badge when active, routes to MIDI channel 9
- Instrument preset list shows 🥁 prefix for bank=128 presets
Export installed pyfluidsynth is actually the low-level ctypes
wrapper (fluidsynth), not the high-level FluidSynth class. The
broken call fluidsynth.FluidSynth() caused silent fallback to
oscillator synth for ALL SoundFont renders. Replace with:
new_fluid_settings / new_fluid_synth / fluid_synth_sfload /
fluid_synth_program_select / fluid_synth_write_s16_stereo.
Also fix synth time advancement: call write_s16_stereo for
silence gaps instead of just advancing a cursor.
- _find_sf2_path now case-insensitive to match catalog IDs
- serializeTracksList includes synth_engine, soundfont_id, instrument_source
- deserializeTracksList restores synth_engine and soundfont_id
3dtours