astrobleem · Oct 25, 2026 · Oct 25, 2026 · Oct 25, 2026 · Oct 25, 2026 · Oct 25, 2026
diff --git a/.gitattributes b/.gitattributes
@@ -3,6 +3,7 @@
 *.py text eol=lf
 *.md text eol=lf
 *.json text eol=lf
+sound/tests/audition/*.H text eol=crlf
 
 # Preserve the approved binary stream and literal per-note audit bytes.
 examples/doebel/DOEBEL.VGM binary

diff --git a/AGENTS.md b/AGENTS.md
@@ -5,8 +5,7 @@ instrument banks, start in `sound/INSTR.C` and `sound/MIDISYN.C`, not the
 native `src/lt_audio.c` / `lt_score.c` / `lt_sfx.c` APIs. Read
 [`docs/PSG-BANKS.md`](docs/PSG-BANKS.md) before changing the bank contract.
 
-- Keep the existing bank as Default, with identical output. The next bank
-  task adds one contrasting bank and a developer host A/B audition using
+- Keep the existing bank as Default, with identical output. Chamber adds one contrasting bank; the developer host A/B audition uses
   identical notes, timing, programs and controllers. No accepted song edits,
   SoundFont/sample claims, extra sound driver or consumer Python preparation.
 - `sound/` owns portable instrument behavior; libwintandy owns Windows
@@ -15,8 +14,8 @@ native `src/lt_audio.c` / `lt_score.c` / `lt_sfx.c` APIs. Read
 - Use C89, fixed-size state and integer arithmetic. No heap, OS calls, port
   I/O, timer ownership or interrupt work in the portable renderer. Preserve
   16-bit near/far contracts and bounded work after long foreground stalls.
-- `MSReset`, `MSSpeakerMode` and flags control existing behavior; no bank
-  selector exists yet. Preserve controller, allocation, reset and mute
+- `MSReset`, `MSSpeakerMode` and flags control existing behavior; the
+  selector is `MSBank` (Default/Chamber). Preserve controller, allocation, reset and mute
   semantics. Direct state changes require `MSInvalidate` before rendering.
 - Host GCC checks do not qualify 8088 code size, Win16 DGROUP/ABI, audibility
   or hardware timing. Report those separately and measure added table/state
@@ -25,8 +24,8 @@ native `src/lt_audio.c` / `lt_score.c` / `lt_sfx.c` APIs. Read
 - On Chad's Windows host, run GCC only through
   `C:\Users\chad\Documents\Codex\toolchains\gcc-ucrt64.py`; never start raw
   GCC/cc1. Uppercase `.C` inputs need `-x c`. Developer Python is allowed.
-- For the current documentation/bank handoff, do not launch emulators or
-  touch the separate VGM player/format/decompression task. Keep changes in
+- For portable bank changes, do not launch emulators or touch the separate
+  Windows player, transport or format/decompression task. Keep changes in
   isolated checkouts. Publication requires explicit approval.
 
 There is no `BUILDING` file: `README.md`, `tools/build.py`, and

diff --git a/README.md b/README.md
@@ -95,12 +95,13 @@ needed. The launcher runs its DLL preflight before compiler startup. These
 options do not change the DOS build.
 
 On Chad's Windows host, use the established launcher; do not start raw
-GCC/cc1. The standalone MIDI runner accepts only one compiler executable,
-so its Windows invocation is documented separately in
-[the PSG bank source map](docs/PSG-BANKS.md#windows-host-checks).
+GCC/cc1. Both host runners accept the approved launcher. Selectable
+Default/Chamber banks and the per-note audition regression are documented
+in [the PSG bank source map](docs/PSG-BANKS.md).
 
 ```powershell
 python tools/build.py --target host --gcc-launcher C:/Users/chad/Documents/Codex/toolchains/gcc-ucrt64.py --runtime-bin C:/msys64/ucrt64/bin
+python sound/tests/run.py --gcc-launcher C:/Users/chad/Documents/Codex/toolchains/gcc-ucrt64.py
 ```
 
 Build logs and a result manifest are local under `build/`. Host tests exercise

diff --git a/docs/PSG-BANKS.md b/docs/PSG-BANKS.md
@@ -1,131 +1,107 @@
-# Selectable PSG banks: source map and handoff
+# Default and Chamber PSG banks
+
+The portable MIDI renderer offers Default (0) and Chamber (1). Default keeps
+the original output. Chamber adds eight melodic attenuation curves. Notes,
+programs, controllers, percussion and speaker routing keep their meaning.
+
+## Selection and lifetime
+
+`MSBank(MSYN *, id)` returns zero on success. An invalid ID returns nonzero
+without changing state. A melodic note latches selection in `TVOICE.bank`
+at note-on. Held and pedal-released voices retain their existing curves.
+`TVOICE.preset` keeps its original 0..10 meaning; never encode bank in it.
+`MSReset` restores Default; callers reapply their explicit selection after
+each reset and preserve per-voice bank state during live rebuilding.
+
+Program changes, CC121/123 and zero CC0/32 do not select a bank. Nonzero
+CC0/32 remain unsupported by low-level admission; the Windows file producer
+skips them separately. `MSSpeakerMode` controls speaker/folding behavior;
+synth flags control envelopes/vibrato. Neither selects instruments. Direct
+voice/controller changes require `MSInvalidate` before `MSRender`.
+
+## Curves and source ownership
+
+`sound/INSTR.C` owns `curves[19][16]`. Original rows0..10 are unchanged:
+eight melodic presets and kick/snare/hat. Chamber rows11..18 provide
+plucked keys, swelling organ, soft bass, slow pad, breathy reed, fading
+lead, mallet and blip. Values are PSG attenuation0..15 at55ms steps.
+Step15 holds unless it is15, which ends the voice. There is no separate
+note-off release envelope. Chamber attacks take up to165ms to contribute
+PCM in the audition; short bell/hit curves can decay before key release.
+
+Melodic programs select `program[channel] >> 4`. Presets3..5 retain
+divider vibrato after eight steps. CC1 changes its depth; CC7/11 affect
+attenuation; CC64 defers note-off; bend is fixed at +/-2 semitones. The
+optional PIT speaker ignores PSG curves. No samples or SoundFonts are added.
+Production rendering remains C89, integer, fixed storage and bounded lookup,
+with no heap, OS, ports, timer or IRQ ownership.
+
+| Repository/path | Role |
+| --- | --- |
+| libtandy `sound/INSTR.*`, `MIDISYN.*` | Canonical bank tables, allocation and rendering. |
+| libtandy `sound/SMF.*` | Buffered parser:60000bytes,32768events,16tracks. |
+| libtandy `tools/psgaudit.c` | Developer host A/B mixer, an approximation of PSG output. |
+| libwintandy `libtandywin/AUDIO/SOURCE/` | Windows vendor and MIDI/speaker integration. |
+| OEMSound `experimental/WINLIB30/SOURCE/` | Matching current player engine mirror. |
+| OEMSound `src/win30/PLAYER/` | MINIPLAY UI and persistent Default/Chamber choice. |
+| OEMSound `src/win30/DRIVER/` | The one shared SOUND.DRV. |
+
+Windows preserves newer speaker fallback and streaming SMF (1MiB,
+65000events,16tracks,64-byte windows). Port focused hunks, never overwrite
+that parser/renderer with this portable version. libtandy `src/lt_audio.c`,
+`lt_score.c`, `lt_sfx.c` and libwintandy `sound/` are separate APIs.
+
+The qualified Windows integration uses `MDInstrumentBank` (ordinal19),
+`MDSeedBank` (20), and `MciBank` (905). Both MIDICLK renderers (`synth` and
+`folded`) reapply selection after resets, and live seeding preserves each
+voice's bank. MINIPLAY stores selection in app-local WINAMP.INI. Windows
+evidence is in libwintandy `docs/BANKS.TXT` and the source-pinned
+`libtandywin/AUDIO/TESTS/NATIVE/BANKS.JSN`.
+
+## Host checks and unchanged auditions
+
+On POSIX use `python3 sound/tests/run.py --cc gcc`. On Chad's Windows host:
 
-Audited against libtandy main `8a0313625382bf1b9fd16843336d9f4b2f577e44`,
-libwintandy main `0e2a65eeedd2b49d5b5fce689eeac39e97fb9477`, and
-OEMSound main `537ebc5363c3d6750f554bb955d96ec9f4ce833f` on 2026-10-25.
-This guides future implementation; this documentation change adds no bank
-or selection API.
+```powershell
+python sound/tests/run.py --gcc-launcher C:/Users/chad/Documents/Codex/toolchains/gcc-ucrt64.py
+python tools/build.py --target host --gcc-launcher C:/Users/chad/Documents/Codex/toolchains/gcc-ucrt64.py --runtime-bin C:/msys64/ucrt64/bin
+```
 
-## Source ownership
+The Windows runner refuses raw GCC and uses the launcher's DLL preflight.
+The suite includes76 MIDI checks,111 bank checks and two Default traces
+(including repeated `MSBank(0)`): `70D11B5D`,6634events,9798renders. Cases
+cover presets, controllers, flat/envelope/vibrato, speaker, cache and stalls.
 
-| Owner / path | Current role |
-| --- | --- |
-| libtandy `sound/INSTR.C`, `INSTR.H` | Canonical compact curves, `TVOICE`, `InstStart`, `InstRead`. |
-| libtandy `sound/MIDISYN.C`, `MIDISYN.H` | `MSYN`, program-to-preset mapping, allocation, controllers, note-off, render cache. |
-| libtandy `sound/MIDIMSG.H`, `LTPBASE.H` | MIDI admission, integer widths, envelope/vibrato flags. |
-| libtandy `sound/tests/portable_midi.c`, `tests/run.py` | Standalone parser/renderer checks. |
-| libwintandy `libtandywin/AUDIO/SOURCE/` | Vendored `INSTR.*` / `MIDISYN.*`; `MIDICLK.C` owns foreground rendering and paired speaker/PSG fallback. `MDAPI.H` / `MIDICLK.DEF` define its API. |
-| Same Windows directory: `MCITNDY.C`, `MCIPSG.C`, `SMF.*`, `MIDISKIP.H` | Streamed validation, admission and event production into MIDICLK. |
-| OEMSound `experimental/WINLIB30/SOURCE/` | Matching Windows source mirror consumed by `tools/WINAMP/PACK.PY` / `VERIFY.PY`. Despite the directory name, it supplies the current player engine. |
-| OEMSound `src/win30/DRIVER/` | Canonical unified `SOUND.DRV`; retain existing ownership and speaker transport. Bank tables do not belong here. |
-
-`libtandy/src/lt_audio.c`, `lt_score.c`, and `lt_sfx.c` are separate native
-PSG APIs, not MIDI banks. `libwintandy/sound/` is a separate pinned producer
-compatibility module, not the player's synth. OEMSound's Winamp UI lives in
-`experimental/WINAMP30/`; its player, format and decompression work is active
-in another task and outside this handoff.
-
-At these revisions `INSTR.C` / `INSTR.H` match across the canonical core,
-Windows vendor and OEMSound mirror. Windows `MIDISYN.*` / `SMF.*` differ
-from the standalone core and match the OEMSound mirror. Preserve the newer
-Windows speaker-fallback and streamed-file changes when porting focused
-instrument changes. Coordinate mirror updates explicitly; do not overwrite
-the published Windows engine with the older portable parser/renderer.
-
-## Actual instrument controls
-
-- `INSTR.C` has `curves[11][16]`: eight melodic presets (keys, organ,
-  bass, pad, reed, lead, bell, hit) and three percussion presets (kick,
-  snare, hat). The table occupies 176 bytes before linker overhead.
-- Entries are PSG attenuation 0..15 at 55 ms steps. Index 15 holds unless
-  its value is 15, which ends the voice. Updates jump to the current index
-  after a stall, with no catch-up loop. Attack/decay/held-level shapes are
-  table values, not ADSR parameters.
-- Melodic program 0..127 selects `program[channel] >> 4`: eight groups of
-  sixteen programs. Program changes affect subsequent note-ons. Channel 10
-  percussion chooses presets 8..10 and noise settings in `MIDISYN.C`,
-  independently of the melodic program mapping.
-- Velocity adds attenuation; CC7/CC11 add quantized channel gain. CC64
-  defers note-off until pedal lift. Other note-off mutes immediately:
-  there is no separate release-envelope stage or release-time knob.
-- Presets 3..5 support divider-based vibrato after eight steps, with an
-  eight-step motion cycle. CC1 affects depth; divider quantization limits
-  high notes. Bend is fixed at +/-2 semitones. Pan is stored but output
-  remains mono; CC91/93 add no reverb/chorus effect.
-- The PSG has three square-wave tones and one noise voice. The optional
-  PIT voice has fixed amplitude with a zero/nonzero gain gate and does not
-  use PSG curves. No samples, filters, PWM, arbitrary waveform timbres or
-  SoundFont loading are provided.
-
-## Existing hooks and missing selector
-
-`MSReset` initializes flags to 3 (envelopes plus optional vibrato).
-`MSSpeakerMode` controls legacy/prepared-speaker/low-note-fold routing, not
-banks. `MSMessage[Deferred]` / `MSRender` apply events and render state;
-`MSInvalidate` marks direct changes for the render cache.
-
-Windows `MDVoiceMode` (export ordinal 16) accepts flags 0, 1 or 3 in
-`MD_OPEN`, before the first successful `MDPush` or `MDCommit` (`haveTime`
-and `committed` must both be zero); `MDOpen` defaults voice flags to 1.
-This controls envelopes/vibrato, not banks. The older direct-driver
-`MODM_SYNTHCONFIG` in `MIDIAPI.H` also controls flags. No bank field, setter
-or export exists in `MSYN` / `MDAPI.H`; player MCI `MC_SET` handles time
-format only.
-
-Low-level `MIDIMSG.H` rejects nonzero CC0/CC32. The Windows file producer
-uses `MIDISKIP.H` to skip unsupported nonzero bank selects, keeping the one
-bank and honoring program changes. Zero bank select is an admitted no-op.
-These are different policies, neither an alternate-bank selector. A future
-explicit API must define invalid IDs, reset/default behavior, active-note
-behavior and cache invalidation, keeping Windows `synth` / `folded` in sync.
-
-## Scope, size and acceptance
-
-Preserve Default output exactly, add one contrasting local bank, and provide
-a developer host A/B audition of the same event sequence. Keep notes,
-programs, controllers, velocity and timing identical between takes. Use
-original synthetic fixtures; do not edit accepted songs or require consumer
-Python/modern-PC preparation. Traces establish output equivalence; an audible
-host preview must actually render audio and label its limits.
-
-Keep C89, integer math, fixed storage, O(1) lookup and existing foreground
-scheduling. No heap, new driver, timer/IRQ owner or large per-voice bank copy.
-Account for tables once and per-`MSYN` additions twice in MIDICLK (`synth`
-and `folded`). Preserve the DS near-pointer scratch storage noted in
-`MSRender`; Win16 DLL SS and DS need not match.
-
-The current Windows receipt `libtandywin/AUDIO/TESTS/NATIVE/MIDI8.MD`
-records MIDICLK CODE/DGROUP minima 14352/12018 bytes, MCITNDY 10948/3398,
-and RAWCLK 13800/27168. MIDICLK code is movable/discardable/preloaded;
-data remains fixed/shared. The DLLs have zero local heap/private stack.
-Report added code/data and native map/segment evidence; host `sizeof` does
-not prove 16-bit layout. Respect segment limits and the 640 KB real-mode
-budget; host checks alone cannot establish that a new bank fits.
-
-Parser versions differ: standalone `sound/SMF.H` is buffered, limited to
-60000 bytes / 32768 channel events / 16 tracks. Windows `SMF.H` streams
-up to 1 MiB / 65000 events / 16 tracks with 64-byte track windows; its
-memory-buffer convenience API retains a single-segment limit.
-
-Implementation checks: Default traces before/after across all presets and
-flat/envelope/vibrato modes; alternate audible difference; invalid IDs and
-reset/switch/active-note behavior; note-off/sustain, CC7/11/1, pitch bend,
-steal, percussion, long stall and render cache; paired speaker/folded
-consistency. Retain parser/controller regressions. Native qualification is
-a separate explicitly scheduled step; no emulator launch in this handoff.
-
-## Windows host checks
-
-From the libtandy root (developer Python only):
+The actual audition mixer is privately instrumented without changing its
+source or writing WAVs. Every expected nonzero-velocity note-on must allocate
+and contribute to quantized final PCM, allowing attack delay. All154 notes
+contribute, with zero missing/clipped/rejected/stolen notes in these scenes.
+A deliberately muted phrase note must be detected as exactly one missing
+voice despite nonzero mixed output. Velocity-zero note-ons are note-offs.
+This is stronger than whole-scene RMS/peak alone.
+
+For a read-only comparison against all eight existing approved takes:
 
 ```powershell
-python tools/build.py --target host --gcc-launcher C:/Users/chad/Documents/Codex/toolchains/gcc-ucrt64.py --runtime-bin C:/msys64/ucrt64/bin
-python C:/Users/chad/Documents/Codex/toolchains/gcc-ucrt64.py -- -x c -std=c89 -pedantic-errors -Wall -Wextra -Werror -Wno-misleading-indentation -Wno-sign-compare -Wno-unused-function -O2 -DSYNTH_HOST -I sound sound/INSTR.C sound/MIDISYN.C sound/SMF.C sound/tests/portable_midi.c -o build/host/portable_midi.exe
-& ./build/host/portable_midi.exe
+python sound/tests/audition/run.py --gcc-launcher C:/Users/chad/Documents/Codex/toolchains/gcc-ucrt64.py --audio C:/Users/chad/work/out/audition
 ```
 
-The first command creates `build/host`. `sound/tests/run.py --cc gcc` is
-the POSIX/ordinary compiler recipe; it accepts one executable and cannot
-invoke the Python launcher via multiword `--cc`. Use the explicit Windows
-command above. Integration MIDI checks are in libwintandy `docs/BUILD.TXT`.
-Host checks do not qualify native timing, audio or code size.
+The separate developer tool `tools/psgaudit.c <existing-output-directory>`
+renders A/B WAVs with identical events and gain, without normalization.
+These host previews do not claim physical Tandy output. No audition or
+accepted song is changed by these tests.
+
+## Size and native evidence
+
+Tables add128bytes. Open Watcom `-ms -0 -os` measured INSTR code+19 and
+MIDISYN+47bytes. Two-byte packing uses existing padding; packed-one-byte
+layouts add five bytes per MSYN. Windows MSC6 measured TVOICE10/MSYN332,
+MIDICLK CODE14844/DGROUP12148 (+492/+130), MCITNDY11192/3404 (+244/+6),
+and MINIPLAY48202/16016 (+688/+416). Corrected RAWCLK paired-live handling
+adds67code bytes; DGROUP27168 and SOUND.DRV remain unchanged.
+
+Host checks alone do not establish Win16 ABI or hardware timing. Windows
+evidence keeps85 file-player checks and28 corrected live-bank checks distinct
+from the17-check exact-final-ZIP install/play/Stop/Close/DOS-cleanup smoke.
+The older file suite is not relabelled as a rerun. No physical hardware
+test is claimed. The merged Doebel example remains unchanged.
diff --git a/sound/INSTR.C b/sound/INSTR.C
@@ -1,7 +1,7 @@
 /* Original 55 ms attenuation curves; no game data or interrupt code.
    Indexed snapshots make each update O(1), even after a long GUI stall. */
 #include "INSTR.H"
-static LTP_U8 curves[11][16]={
+static LTP_U8 curves[19][16]={
  {0,0,1,2,3,4,5,6,7,8,8,8,8,8,8,8}, /* keys */
  {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}, /* organ */
  {0,0,1,1,2,2,3,3,4,4,5,5,5,5,5,5}, /* bass */
@@ -12,20 +12,30 @@ static LTP_U8 curves[11][16]={
  {0,2,4,6,8,10,12,14,15,15,15,15,15,15,15,15}, /* hit */
  {1,2,4,7,10,13,15,15,15,15,15,15,15,15,15,15}, /* kick */
  {0,2,5,8,11,15,15,15,15,15,15,15,15,15,15,15}, /* snare */
- {2,6,10,15,15,15,15,15,15,15,15,15,15,15,15,15} /* hat */
+ {2,6,10,15,15,15,15,15,15,15,15,15,15,15,15,15}, /* hat */
+ /* Chamber bank (rows 11..18): same preset order. Peaks match Default;
+    contrast is attack, decay and held level. 15 ends a voice anywhere. */
+ {0,1,3,5,7,9,10,10,10,10,10,10,10,10,10,10}, /* plucked keys */
+ {7,5,3,2,1,0,0,0,0,0,0,0,0,0,0,0}, /* swelling organ */
+ {0,1,2,4,6,7,8,8,8,8,8,8,8,8,8,8}, /* soft bass */
+ {14,12,10,8,6,5,4,3,2,2,2,2,2,2,2,2}, /* slow pad */
+ {9,6,4,2,1,0,0,1,1,1,1,1,1,1,1,1}, /* breathy reed */
+ {0,0,1,3,5,6,6,6,6,6,6,6,6,6,6,6}, /* fading lead */
+ {0,2,5,8,11,13,15,15,15,15,15,15,15,15,15,15}, /* mallet */
+ {0,3,7,11,15,15,15,15,15,15,15,15,15,15,15,15} /* blip */
 };
 static signed char motion[8]={0,1,2,1,0,-1,-2,-1};
 void InstStart(TVOICE *v,unsigned preset,unsigned volume,
                unsigned period,LTP_U32 step)
 {
     v->began=step;v->period=period;
-    v->velocity=(LTP_U8)volume;v->preset=(LTP_U8)preset;
+    v->velocity=(LTP_U8)volume;v->preset=(LTP_U8)preset;v->bank=0;
 }
 int InstRead(TVOICE *v,LTP_U32 step,LTP_U16 flags,LTP_U16 *period,LTP_U16 *volume)
 {
     LTP_U32 elapsed;unsigned n,a,depth;int delta,p;
     elapsed=step-v->began;n=elapsed>15UL?15:(unsigned)elapsed;
-    a=curves[v->preset][n];
+    a=curves[v->bank?v->preset+11:v->preset][n];
     if(a==15){*volume=15;*period=v->period;return 0;}
     a+=v->velocity;*volume=a>15?15:a;p=v->period;
     if(((flags&LTP_VIBRATO) || v->modulation) && elapsed>=8UL &&

diff --git a/sound/INSTR.H b/sound/INSTR.H
@@ -5,7 +5,7 @@
 typedef struct {
     LTP_U32 began;
     LTP_U16 period;
-    LTP_U8 velocity,preset,modulation;
+    LTP_U8 velocity,preset,modulation,bank;
 } TVOICE;
 void InstStart(TVOICE *,unsigned,unsigned,unsigned,LTP_U32);
 int InstRead(TVOICE *,LTP_U32,LTP_U16,LTP_U16 *,LTP_U16 *);