diff --git a/.vscode/settings.json b/.vscode/settings.json
index 8f78dba0..dcd6c9da 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -51,7 +51,9 @@
     "dsp.h": "c",
     "ar.h": "c",
     "osrtcpriv.h": "c",
-    "osbootinfo.h": "c"
+    "osbootinfo.h": "c",
+    "assert.h": "c",
+    "math.h": "c"
   },
   "files.autoSave": "onFocusChange",
   "files.insertFinalNewline": true,
diff --git a/asm/musyx/reverb.s b/asm/musyx/reverb.s
index 0111e89d..cc76339e 100644
--- a/asm/musyx/reverb.s
+++ b/asm/musyx/reverb.s
@@ -545,8 +545,7 @@ lbl_803B6164:
 /* 803B6254 003B31B4  38 21 00 30 */	addi r1, r1, 0x30
 /* 803B6258 003B31B8  4E 80 00 20 */	blr
 
-.global HandleReverb_0
-HandleReverb_0:
+.fn HandleReverb, local
 /* 803B625C 003B31BC  94 21 FF 40 */	stwu r1, -0xc0(r1)
 /* 803B6260 003B31C0  BD C1 00 08 */	stmw r14, 8(r1)
 /* 803B6264 003B31C4  D9 C1 00 60 */	stfd f14, 0x60(r1)
@@ -899,6 +898,7 @@ lbl_803B66C0:
 /* 803B675C 003B36BC  B9 C1 00 08 */	lmw r14, 8(r1)
 /* 803B6760 003B36C0  38 21 00 C0 */	addi r1, r1, 0xc0
 /* 803B6764 003B36C4  4E 80 00 20 */	blr
+.endfn HandleReverb
 
 .global ReverbHICallback
 ReverbHICallback:
@@ -941,19 +941,19 @@ lbl_803B67E8:
 /* 803B67E8 003B3748  7F 63 DB 78 */	mr r3, r27
 /* 803B67EC 003B374C  7F C4 F3 78 */	mr r4, r30
 /* 803B67F0 003B3750  38 A0 00 00 */	li r5, 0
-/* 803B67F4 003B3754  4B FF FA 69 */	bl HandleReverb_0
+/* 803B67F4 003B3754  4B FF FA 69 */	bl HandleReverb
 /* 803B67F8 003B3758  48 00 00 28 */	b lbl_803B6820
 lbl_803B67FC:
 /* 803B67FC 003B375C  7F 83 E3 78 */	mr r3, r28
 /* 803B6800 003B3760  7F C4 F3 78 */	mr r4, r30
 /* 803B6804 003B3764  38 A0 00 01 */	li r5, 1
-/* 803B6808 003B3768  4B FF FA 55 */	bl HandleReverb_0
+/* 803B6808 003B3768  4B FF FA 55 */	bl HandleReverb
 /* 803B680C 003B376C  48 00 00 14 */	b lbl_803B6820
 lbl_803B6810:
 /* 803B6810 003B3770  7F A3 EB 78 */	mr r3, r29
 /* 803B6814 003B3774  7F C4 F3 78 */	mr r4, r30
 /* 803B6818 003B3778  38 A0 00 02 */	li r5, 2
-/* 803B681C 003B377C  4B FF FA 41 */	bl HandleReverb_0
+/* 803B681C 003B377C  4B FF FA 41 */	bl HandleReverb
 lbl_803B6820:
 /* 803B6820 003B3780  3B FF 00 01 */	addi r31, r31, 1
 lbl_803B6824:
diff --git a/configure.py b/configure.py
index 77147bfd..46c778d1 100755
--- a/configure.py
+++ b/configure.py
@@ -940,8 +940,8 @@ LIBS = [
             "musyx/hw_volconv",
             ["musyx/snd3d", False],
             ["musyx/snd_init", True],
-            ["musyx/snd_math", False],
-            "musyx/snd_midictrl",
+            ["musyx/snd_math", True],
+            ["musyx/snd_midictrl", False],
             ["musyx/snd_service", True],
             ["musyx/hardware", False],
             "musyx/hw_aramdma",
@@ -953,7 +953,7 @@ LIBS = [
             ["musyx/reverb_fx", True],
             ["musyx/reverb", False],
             ["musyx/delay_fx", True],
-            "musyx/chorus_fx",
+            ["musyx/chorus_fx", True],
         ],
     },
     {
@@ -1133,7 +1133,10 @@ if __name__ == "__main__":
         n.variable("devkitppc", "/opt/devkitpro/devkitPPC")
     cflags_base = "-proc gekko -nodefaults -Cpp_exceptions off -RTTI off -fp hard -fp_contract on -O4,p -maxerrors 1 -enum int -inline auto -str reuse -nosyspath -MMD -DPRIME1 -DVERSION=$version_num -DNONMATCHING=0 -i include/ -i libc/"
     if args.debug:
-        cflags_base += " -sym on"
+        cflags_base += " -sym on -D_DEBUG"
+    else:
+        cflags_base += " -DNDEBUG"
+
     n.variable("cflags_base", cflags_base)
     n.variable(
         "cflags_retro",
@@ -1143,7 +1146,7 @@ if __name__ == "__main__":
         "cflags_runtime",
         "$cflags_base -use_lmw_stmw on -str reuse,pool,readonly -gccinc -inline deferred,auto",
     )
-    n.variable("cflags_musyx", "$cflags_base -str reuse,pool,readonly")
+    n.variable("cflags_musyx", "$cflags_base -str reuse,pool,readonly -fp_contract off")
     asflags = "-mgekko -I include/ --defsym version=$version_num -W --strip-local-absolute -gdwarf-2"
     n.variable("asflags", asflags)
     ldflags = "-fp fmadd -nodefaults -lcf ldscript.lcf"
diff --git a/include/musyx/assert.h b/include/musyx/assert.h
new file mode 100644
index 00000000..b6664204
--- /dev/null
+++ b/include/musyx/assert.h
@@ -0,0 +1,32 @@
+#ifndef _MUSYX_ASSERT
+#define _MUSYX_ASSERT
+
+extern void OSPanic(const char* file, int line, const char* msg, ...);
+
+#ifndef ASSERT
+#ifdef _DEBUG
+#define ASSERT(cond) \
+  do { \
+    if (!cond) { \
+      OSPanic(__FILE__, __LINE__, "Failed assertion " #cond); \
+    } \
+  } while(0)
+#else
+#define ASSERT(cond)
+#endif
+#endif
+
+#ifndef ASSERT_MSG
+#ifdef _DEBUG
+#define ASSERT_MSG(cond, msg) \
+  do { \
+    if (!cond) { \
+      OSPanic(__FILE__, __LINE__, msg); \
+    } \
+  } while(0)
+#else
+#define ASSERT_MSG(cond, msg)
+#endif
+#endif
+
+#endif // _MUSYX_ASSERT
diff --git a/include/musyx/musyx.h b/include/musyx/musyx.h
index 810a448f..7981a76a 100644
--- a/include/musyx/musyx.h
+++ b/include/musyx/musyx.h
@@ -236,7 +236,49 @@ SND_VOICEID sndFXCheck(SND_VOICEID vid);
 bool sndFXKeyOff(SND_VOICEID vid);
 bool sndFXCtrl(SND_VOICEID vid, u8 ctrl, u8 value);
 bool sndFXCtrl14(SND_VOICEID vid, u8 ctrl, u16 value);
+#define _SND_CHORUS_NUM_BLOCKS 3
+typedef struct _SND_CHORUS_SRCINFO {
+  s32* dest;
+  s32* smpBase;
+  s32* old;
+  u32 posLo;
+  u32 posHi;
+  u32 pitchLo;
+  u32 pitchHi;
+  u32 trigger;
+  u32 target;
+} _SND_CHORUS_SRCINFO;
 
+typedef struct _SND_CHORUS_WORK {
+  s32* lastLeft[_SND_CHORUS_NUM_BLOCKS];
+  s32* lastRight[_SND_CHORUS_NUM_BLOCKS];
+  s32* lastSur[_SND_CHORUS_NUM_BLOCKS];
+  u8 currentLast;
+  s32 oldLeft[4];
+  s32 oldRight[4];
+  s32 oldSur[4];
+
+  u32 currentPosLo;
+  u32 currentPosHi;
+
+  s32 pitchOffset;
+  u32 pitchOffsetPeriodCount;
+  u32 pitchOffsetPeriod;
+
+  _SND_CHORUS_SRCINFO src;
+} _SND_CHORUS_WORK;
+
+typedef struct SND_AUX_CHORUS {
+  _SND_CHORUS_WORK work;
+  u32 baseDelay;
+  u32 variation;
+  u32 period;
+} SND_AUX_CHORUS;
+
+void sndAuxCallbackChorus(u8 reason, SND_AUX_INFO* info, void* user);
+bool sndAuxCallbackPrepareChorus(SND_AUX_CHORUS* ch);
+bool sndAuxCallbackShutdownChorus(SND_AUX_CHORUS* ch);
+bool sndAuxCallbackUpdateSettingsChorus(SND_AUX_CHORUS* ch);
 #ifdef __cplusplus
 }
 #endif
diff --git a/libc/math.h b/libc/math.h
index 5e9f359a..0ad14fe5 100644
--- a/libc/math.h
+++ b/libc/math.h
@@ -89,6 +89,7 @@ double copysign(double x, double y);
 double floor(double x);
 
 double fabs(double x);
+double pow(double x, double y);
 
 #ifdef __MWERKS__
 #pragma cplusplus on
diff --git a/src/musyx/chorus_fx.c b/src/musyx/chorus_fx.c
new file mode 100644
index 00000000..b1c0135a
--- /dev/null
+++ b/src/musyx/chorus_fx.c
@@ -0,0 +1,540 @@
+#include "musyx/musyx_priv.h"
+#include "musyx/assert.h"
+
+static float rsmpTab12khz[512] = {
+    0.097503662109f,  0.802215576172f,  0.101593017578f,  -0.000976562500f, 0.093505859375f,
+    0.802032470703f,  0.105804443359f,  -0.001037597656f, 0.089599609375f,  0.801696777344f,
+    0.110107421875f,  -0.001159667969f, 0.085784912109f,  0.801177978516f,  0.114471435547f,
+    -0.001281738281f, 0.082031250000f,  0.800476074219f,  0.118927001953f,  -0.001403808594f,
+    0.078369140625f,  0.799621582031f,  0.123474121094f,  -0.001525878906f, 0.074798583984f,
+    0.798614501953f,  0.128143310547f,  -0.001647949219f, 0.071350097656f,  0.797424316406f,
+    0.132873535156f,  -0.001770019531f, 0.067962646484f,  0.796051025391f,  0.137695312500f,
+    -0.001922607422f, 0.064697265625f,  0.794525146484f,  0.142608642578f,  -0.002044677734f,
+    0.061492919922f,  0.792846679688f,  0.147613525391f,  -0.002197265625f, 0.058349609375f,
+    0.790985107422f,  0.152709960938f,  -0.002319335938f, 0.055328369141f,  0.788940429688f,
+    0.157897949219f,  -0.002471923828f, 0.052368164062f,  0.786743164062f,  0.163177490234f,
+    -0.002655029297f, 0.049499511719f,  0.784423828125f,  0.168518066406f,  -0.002807617188f,
+    0.046722412109f,  0.781890869141f,  0.173980712891f,  -0.002990722656f, 0.044006347656f,
+    0.779205322266f,  0.179504394531f,  -0.003143310547f, 0.041412353516f,  0.776367187500f,
+    0.185119628906f,  -0.003326416016f, 0.038879394531f,  0.773376464844f,  0.190826416016f,
+    -0.003509521484f, 0.036407470703f,  0.770233154297f,  0.196594238281f,  -0.003692626953f,
+    0.034027099609f,  0.766937255859f,  0.202484130859f,  -0.003875732422f, 0.031738281250f,
+    0.763488769531f,  0.208435058594f,  -0.004058837891f, 0.029510498047f,  0.759857177734f,
+    0.214447021484f,  -0.004272460938f, 0.027374267578f,  0.756103515625f,  0.220550537109f,
+    -0.004455566406f, 0.025299072266f,  0.752197265625f,  0.226745605469f,  -0.004669189453f,
+    0.023315429688f,  0.748168945312f,  0.233001708984f,  -0.004852294922f, 0.021392822266f,
+    0.743988037109f,  0.239318847656f,  -0.005065917969f, 0.019561767578f,  0.739654541016f,
+    0.245727539062f,  -0.005310058594f, 0.017791748047f,  0.735198974609f,  0.252197265625f,
+    -0.005523681641f, 0.016052246094f,  0.730590820312f,  0.258728027344f,  -0.005706787109f,
+    0.014404296875f,  0.725860595703f,  0.265350341797f,  -0.005920410156f, 0.012817382812f,
+    0.721008300781f,  0.272033691406f,  -0.006164550781f, 0.011322021484f,  0.716003417969f,
+    0.278778076172f,  -0.006378173828f, 0.009887695312f,  0.710906982422f,  0.285583496094f,
+    -0.006561279297f, 0.008514404297f,  0.705657958984f,  0.292449951172f,  -0.006774902344f,
+    0.007202148438f,  0.700317382812f,  0.299346923828f,  -0.007019042969f, 0.005920410156f,
+    0.694854736328f,  0.306335449219f,  -0.007232666016f, 0.004699707031f,  0.689270019531f,
+    0.313385009766f,  -0.007415771484f, 0.003570556641f,  0.683563232422f,  0.320465087891f,
+    -0.007629394531f, 0.002471923828f,  0.677734375000f,  0.327606201172f,  -0.007873535156f,
+    0.001434326172f,  0.671844482422f,  0.334777832031f,  -0.008087158203f, 0.000457763672f,
+    0.665832519531f,  0.341979980469f,  -0.008270263672f, -0.000488281250f, 0.659729003906f,
+    0.349243164062f,  -0.008453369141f, -0.001342773438f, 0.653533935547f,  0.356567382812f,
+    -0.008636474609f, -0.002166748047f, 0.647216796875f,  0.363891601562f,  -0.008850097656f,
+    -0.002960205078f, 0.640838623047f,  0.371276855469f,  -0.009033203125f, -0.003692626953f,
+    0.634338378906f,  0.378692626953f,  -0.009216308594f, -0.004364013672f, 0.627777099609f,
+    0.386138916016f,  -0.009338378906f, -0.004974365234f, 0.621154785156f,  0.393615722656f,
+    -0.009490966797f, -0.005584716797f, 0.614440917969f,  0.401092529297f,  -0.009643554688f,
+    -0.006134033203f, 0.607635498047f,  0.408599853516f,  -0.009796142578f, -0.006652832031f,
+    0.600769042969f,  0.416107177734f,  -0.009918212891f, -0.007141113281f, 0.593841552734f,
+    0.423645019531f,  -0.010009765625f, -0.007568359375f, 0.586853027344f,  0.431213378906f,
+    -0.010131835938f, -0.007965087891f, 0.579772949219f,  0.438751220703f,  -0.010223388672f,
+    -0.008331298828f, 0.572662353516f,  0.446319580078f,  -0.010284423828f, -0.008666992188f,
+    0.565521240234f,  0.453887939453f,  -0.010345458984f, -0.008972167969f, 0.558319091797f,
+    0.461456298828f,  -0.010406494141f, -0.009216308594f, 0.551055908203f,  0.469024658203f,
+    -0.010406494141f, -0.009460449219f, 0.543731689453f,  0.476593017578f,  -0.010406494141f,
+    -0.009674072266f, 0.536407470703f,  0.484130859375f,  -0.010375976562f, -0.009857177734f,
+    0.529022216797f,  0.491668701172f,  -0.010375976562f, -0.010009765625f, 0.521606445312f,
+    0.499176025391f,  -0.010314941406f, -0.010131835938f, 0.514160156250f,  0.506683349609f,
+    -0.010253906250f, -0.010253906250f, 0.506683349609f,  0.514160156250f,  -0.010131835938f,
+    -0.010314941406f, 0.499176025391f,  0.521606445312f,  -0.010009765625f, -0.010375976562f,
+    0.491668701172f,  0.529022216797f,  -0.009857177734f, -0.010375976562f, 0.484130859375f,
+    0.536407470703f,  -0.009674072266f, -0.010406494141f, 0.476593017578f,  0.543731689453f,
+    -0.009460449219f, -0.010406494141f, 0.469024658203f,  0.551055908203f,  -0.009216308594f,
+    -0.010406494141f, 0.461456298828f,  0.558319091797f,  -0.008972167969f, -0.010345458984f,
+    0.453887939453f,  0.565521240234f,  -0.008666992188f, -0.010284423828f, 0.446319580078f,
+    0.572662353516f,  -0.008331298828f, -0.010223388672f, 0.438751220703f,  0.579772949219f,
+    -0.007965087891f, -0.010131835938f, 0.431213378906f,  0.586853027344f,  -0.007568359375f,
+    -0.010009765625f, 0.423645019531f,  0.593841552734f,  -0.007141113281f, -0.009918212891f,
+    0.416107177734f,  0.600769042969f,  -0.006652832031f, -0.009796142578f, 0.408599853516f,
+    0.607635498047f,  -0.006134033203f, -0.009643554688f, 0.401092529297f,  0.614440917969f,
+    -0.005584716797f, -0.009490966797f, 0.393615722656f,  0.621154785156f,  -0.004974365234f,
+    -0.009338378906f, 0.386138916016f,  0.627777099609f,  -0.004364013672f, -0.009216308594f,
+    0.378692626953f,  0.634338378906f,  -0.003692626953f, -0.009033203125f, 0.371276855469f,
+    0.640838623047f,  -0.002960205078f, -0.008850097656f, 0.363891601562f,  0.647216796875f,
+    -0.002166748047f, -0.008636474609f, 0.356567382812f,  0.653533935547f,  -0.001342773438f,
+    -0.008453369141f, 0.349243164062f,  0.659729003906f,  -0.000488281250f, -0.008270263672f,
+    0.341979980469f,  0.665832519531f,  0.000457763672f,  -0.008087158203f, 0.334777832031f,
+    0.671844482422f,  0.001434326172f,  -0.007873535156f, 0.327606201172f,  0.677734375000f,
+    0.002471923828f,  -0.007629394531f, 0.320465087891f,  0.683563232422f,  0.003570556641f,
+    -0.007415771484f, 0.313385009766f,  0.689270019531f,  0.004699707031f,  -0.007232666016f,
+    0.306335449219f,  0.694854736328f,  0.005920410156f,  -0.007019042969f, 0.299346923828f,
+    0.700317382812f,  0.007202148438f,  -0.006774902344f, 0.292449951172f,  0.705657958984f,
+    0.008514404297f,  -0.006561279297f, 0.285583496094f,  0.710906982422f,  0.009887695312f,
+    -0.006378173828f, 0.278778076172f,  0.716003417969f,  0.011322021484f,  -0.006164550781f,
+    0.272033691406f,  0.721008300781f,  0.012817382812f,  -0.005920410156f, 0.265350341797f,
+    0.725860595703f,  0.014404296875f,  -0.005706787109f, 0.258728027344f,  0.730590820312f,
+    0.016052246094f,  -0.005523681641f, 0.252197265625f,  0.735198974609f,  0.017791748047f,
+    -0.005310058594f, 0.245727539062f,  0.739654541016f,  0.019561767578f,  -0.005065917969f,
+    0.239318847656f,  0.743988037109f,  0.021392822266f,  -0.004852294922f, 0.233001708984f,
+    0.748168945312f,  0.023315429688f,  -0.004669189453f, 0.226745605469f,  0.752197265625f,
+    0.025299072266f,  -0.004455566406f, 0.220550537109f,  0.756103515625f,  0.027374267578f,
+    -0.004272460938f, 0.214447021484f,  0.759857177734f,  0.029510498047f,  -0.004058837891f,
+    0.208435058594f,  0.763488769531f,  0.031738281250f,  -0.003875732422f, 0.202484130859f,
+    0.766937255859f,  0.034027099609f,  -0.003692626953f, 0.196594238281f,  0.770233154297f,
+    0.036407470703f,  -0.003509521484f, 0.190826416016f,  0.773376464844f,  0.038879394531f,
+    -0.003326416016f, 0.185119628906f,  0.776367187500f,  0.041412353516f,  -0.003143310547f,
+    0.179504394531f,  0.779205322266f,  0.044006347656f,  -0.002990722656f, 0.173980712891f,
+    0.781890869141f,  0.046722412109f,  -0.002807617188f, 0.168518066406f,  0.784423828125f,
+    0.049499511719f,  -0.002655029297f, 0.163177490234f,  0.786743164062f,  0.052368164062f,
+    -0.002471923828f, 0.157897949219f,  0.788940429688f,  0.055328369141f,  -0.002319335938f,
+    0.152709960938f,  0.790985107422f,  0.058349609375f,  -0.002197265625f, 0.147613525391f,
+    0.792846679688f,  0.061492919922f,  -0.002044677734f, 0.142608642578f,  0.794525146484f,
+    0.064697265625f,  -0.001922607422f, 0.137695312500f,  0.796051025391f,  0.067962646484f,
+    -0.001770019531f, 0.132873535156f,  0.797424316406f,  0.071350097656f,  -0.001647949219f,
+    0.128143310547f,  0.798614501953f,  0.074798583984f,  -0.001525878906f, 0.123474121094f,
+    0.799621582031f,  0.078369140625f,  -0.001403808594f, 0.118927001953f,  0.800476074219f,
+    0.082031250000f,  -0.001281738281f, 0.114471435547f,  0.801177978516f,  0.085784912109f,
+    -0.001159667969f, 0.110107421875f,  0.801696777344f,  0.089599609375f,  -0.001037597656f,
+    0.105804443359f,  0.802032470703f,  0.093505859375f,  -0.000976562500f, 0.101593017578f,
+    0.802215576172f,  0.097503662109f,
+};
+
+const double i2fMagic = 4.503601774854144E15;
+
+#if NONMATCHING
+void do_src1(_SND_CHORUS_SRCINFO* src) {
+  // TODO: Match this
+}
+#else
+/* clang-format off */
+#pragma push
+#pragma optimization_level 0
+#pragma optimizewithasm off
+asm void do_src1(_SND_CHORUS_SRCINFO* src) {
+  nofralloc
+  stwu r1, -0x40(r1)
+  stmw r26, 0x28(r1)
+  lwz r4, 0xc(r3)
+  lwz r5, 0x10(r3)
+  lwz r6, 0x14(r3)
+  lwz r8, 0x1c(r3)
+  lwz r7, 0x20(r3)
+  lwz r31, 4(r3)
+  lwz r30, 0(r3)
+  lwz r9, 8(r3)
+  lis r10, 0x4330
+  stw r10, 8(r1)
+  stw r10, 0x10(r1)
+  stw r10, 0x18(r1)
+  stw r10, 0x20(r1)
+  lis r10, i2fMagic@ha
+  lfd f9, i2fMagic@l(r10)
+  slwi r10, r5, 2
+  lwz r11, 0(r9)
+  lwz r29, 4(r9)
+  lwz r28, 8(r9)
+  lwzx r27, r31, r10
+  xoris r11, r11, 0x8000
+  xoris r29, r29, 0x8000
+  stw r11, 0xc(r1)
+  xoris r28, r28, 0x8000
+  stw r29, 0x14(r1)
+  xoris r27, r27, 0x8000
+  stw r28, 0x1c(r1)
+  lfd f1, 8(r1)
+  stw r27, 0x24(r1)
+  lfd f2, 0x10(r1)
+  fsubs f1, f1, f9
+  lfd f3, 0x18(r1)
+  fsubs f2, f2, f9
+  lfd f4, 0x20(r1)
+  fsubs f3, f3, f9
+  fsubs f4, f4, f9
+  li r26, -4
+  lis r12, rsmpTab12khz@ha
+  addi r12, r12, rsmpTab12khz@l
+  li r9, 0xa0
+  mtctr r9
+lbl_803B6D5C:
+  rlwinm r10, r4, 7, 0x15, 0x1b
+  addc r4, r4, r6
+  add r10, r10, r12
+  mcrxr cr0
+  lfs f5, 0(r10)
+  beq lbl_803B6DA4
+  lfs f6, 4(r10)
+  fmuls f10, f1, f5
+  lfs f7, 8(r10)
+  fmadds f10, f2, f6, f10
+  lfs f8, 0xc(r10)
+  fmadds f10, f3, f7, f10
+  addi r30, r30, 4
+  fmadds f10, f4, f8, f10
+  fctiwz f10, f10
+  stfiwx f10, r26, r30
+  bdnz lbl_803B6D5C
+  b lbl_803B6E10
+lbl_803B6DA4:
+  addi r5, r5, 1
+  lfs f6, 4(r10)
+  fmuls f10, f1, f5
+  cmpw r5, r8
+  fmr f1, f2
+  lfs f7, 8(r10)
+  fmadds f10, f2, f6, f10
+  fmr f2, f3
+  lfs f8, 0xc(r10)
+  fmadds f10, f3, f7, f10
+  addi r30, r30, 4
+  fmr f3, f4
+  bne+ lbl_803B6DDC
+  mr r5, r7
+lbl_803B6DDC:
+  fmadds f10, f4, f8, f10
+  slwi r9, r5, 2
+  bdz lbl_803B6E08
+  lwzx r10, r9, r31
+  fctiwz f10, f10
+  xoris r10, r10, 0x8000
+  stw r10, 0xc(r1)
+  stfiwx f10, r26, r30
+  lfd f4, 8(r1)
+  fsubs f4, f4, f9
+  b lbl_803B6D5C
+lbl_803B6E08:
+  fctiwz f10, f10
+  stfiwx f10, r26, r30
+lbl_803B6E10:
+  lwz r9, 8(r3)
+  fctiwz f1, f1
+  fctiwz f2, f2
+  fctiwz f3, f3
+  stfiwx f1, r0, r9
+  addi r10, r9, 4
+  stfiwx f2, r0, r10
+  addi r10, r9, 8
+  stfiwx f3, r0, r10
+  stw r4, 0xc(r3)
+  stw r5, 0x10(r3)
+  lmw r26, 0x28(r1)
+  addi r1, r1, 0x40
+  blr
+}
+#pragma pop
+/* clang-format on */
+#endif
+
+#if NONMATCHING
+void do_src2(_SND_CHORUS_SRCINFO* src) {
+  // TODO: Match this
+}
+#else
+/* clang-format off */
+#pragma push
+#pragma optimization_level 0
+#pragma optimizewithasm off
+asm void do_src2(_SND_CHORUS_SRCINFO* src) {
+  nofralloc
+  stwu r1, -0x40(r1)
+  stmw r26, 0x28(r1)
+  lwz r4, 0xc(r3)
+  lwz r5, 0x10(r3)
+  lwz r6, 0x14(r3)
+  lwz r8, 0x1c(r3)
+  lwz r7, 0x20(r3)
+  lwz r31, 4(r3)
+  lwz r30, 0(r3)
+  lwz r9, 8(r3)
+  lis r10, 0x4330
+  stw r10, 8(r1)
+  stw r10, 0x10(r1)
+  stw r10, 0x18(r1)
+  stw r10, 0x20(r1)
+  lis r10, i2fMagic@ha
+  lfd f9, i2fMagic@l(r10)
+  slwi r10, r5, 2
+  lwz r11, 0(r9)
+  lwz r29, 4(r9)
+  lwz r28, 8(r9)
+  lwzx r27, r31, r10
+  xoris r11, r11, 0x8000
+  xoris r29, r29, 0x8000
+  stw r11, 0xc(r1)
+  xoris r28, r28, 0x8000
+  stw r29, 0x14(r1)
+  xoris r27, r27, 0x8000
+  stw r28, 0x1c(r1)
+  lfd f1, 8(r1)
+  stw r27, 0x24(r1)
+  lfd f2, 0x10(r1)
+  fsubs f1, f1, f9
+  lfd f3, 0x18(r1)
+  fsubs f2, f2, f9
+  lfd f4, 0x20(r1)
+  fsubs f3, f3, f9
+  fsubs f4, f4, f9
+  li r26, -4
+  lis r12, rsmpTab12khz@ha
+  addi r12, r12, rsmpTab12khz@l
+  li r9, 0xa0
+  mtctr r9
+lbl_803B6EF4:
+  rlwinm r10, r4, 7, 0x15, 0x1b
+  addc r4, r4, r6
+  add r10, r10, r12
+  mcrxr cr0
+  addi r5, r5, 1
+  lfs f5, 0(r10)
+  beq lbl_803B6F70
+  lfs f6, 4(r10)
+  fmuls f10, f1, f5
+  cmpw r5, r8
+  fmr f1, f2
+  lfs f7, 8(r10)
+  fmadds f10, f2, f6, f10
+  fmr f2, f3
+  lfs f8, 0xc(r10)
+  fmadds f10, f3, f7, f10
+  addi r30, r30, 4
+  fmr f3, f4
+  bne+ lbl_803B6F44
+  mr r5, r7
+lbl_803B6F44:
+  fmadds f10, f4, f8, f10
+  slwi r9, r5, 2
+  bdz lbl_803B6FF4
+  lwzx r10, r9, r31
+  fctiwz f10, f10
+  xoris r10, r10, 0x8000
+  stw r10, 0xc(r1)
+  stfiwx f10, r26, r30
+  lfd f4, 8(r1)
+  fsubs f4, f4, f9
+  b lbl_803B6EF4
+lbl_803B6F70:
+  cmpw r5, r8
+  lfs f6, 4(r10)
+  bne+ lbl_803B6F80
+  mr r5, r7
+lbl_803B6F80:
+  slwi r11, r5, 2
+  addi r5, r5, 1
+  lwzx r29, r11, r31
+  fmuls f10, f1, f5
+  cmpw r5, r8
+  xoris r29, r29, 0x8000
+  fmr f1, f3
+  lfs f7, 8(r10)
+  stw r29, 0xc(r1)
+  fmadds f10, f2, f6, f10
+  lfs f8, 0xc(r10)
+  fmadds f10, f3, f7, f10
+  lfd f3, 8(r1)
+  fmr f2, f4
+  addi r30, r30, 4
+  fsubs f3, f3, f9
+  bne+ lbl_803B6FC8
+  mr r5, r7
+lbl_803B6FC8:
+  fmadds f10, f4, f8, f10
+  slwi r9, r5, 2
+  bdz lbl_803B6FF4
+  lwzx r10, r9, r31
+  fctiwz f10, f10
+  xoris r10, r10, 0x8000
+  stw r10, 0xc(r1)
+  stfiwx f10, r26, r30
+  lfd f4, 8(r1)
+  fsubs f4, f4, f9
+  b lbl_803B6EF4
+lbl_803B6FF4:
+  fctiwz f10, f10
+  stfiwx f10, r26, r30
+  lwz r9, 8(r3)
+  fctiwz f1, f1
+  fctiwz f2, f2
+  fctiwz f3, f3
+  stfiwx f1, r0, r9
+  addi r10, r9, 4
+  stfiwx f2, r0, r10
+  addi r10, r9, 8
+  stfiwx f3, r0, r10
+  stw r4, 0xc(r3)
+  stw r5, 0x10(r3)
+  lmw r26, 0x28(r1)
+  addi r1, r1, 0x40
+  blr
+}
+#pragma pop
+/* clang-format on */
+#endif
+
+void sndAuxCallbackChorus(u8 reason, SND_AUX_INFO* info, void* user) {
+  SND_AUX_CHORUS* chorus;
+  u8 currLast;
+  s32* lastLeft;
+  s32* lastRight;
+  s32* lastSur;
+  s32* left;
+  s32* right;
+  s32* sur;
+  u32 i;
+  s32 tmp;
+
+  switch (reason) {
+  case SND_AUX_REASON_BUFFERUPDATE:
+    chorus = (SND_AUX_CHORUS*)user;
+    currLast = (chorus->work.currentLast + 1) % 3;
+    lastLeft = chorus->work.lastLeft[currLast];
+    lastRight = chorus->work.lastRight[currLast];
+    lastSur = chorus->work.lastSur[currLast];
+    left = info->data.bufferUpdate.left;
+    right = info->data.bufferUpdate.right;
+    sur = info->data.bufferUpdate.surround;
+
+    for (i = 0; i < 160; ++i) {
+      int tmp = *left;
+      ++left;
+      *lastLeft = tmp;
+      ++lastLeft;
+
+      tmp = *right;
+      ++right;
+      *lastRight = tmp;
+      ++lastRight;
+
+      tmp = *sur;
+      ++sur;
+      *lastSur = tmp;
+      ++lastSur;
+    }
+
+    chorus->work.src.pitchHi = (chorus->work.pitchOffset >> 0x10) + 1;
+    chorus->work.src.pitchLo = (chorus->work.pitchOffset << 0x10);
+
+    tmp = chorus->work.pitchOffsetPeriodCount - 1;
+    chorus->work.pitchOffsetPeriodCount = tmp;
+    if (tmp == 0) {
+      chorus->work.pitchOffsetPeriodCount = chorus->work.pitchOffsetPeriod;
+      chorus->work.pitchOffset = -chorus->work.pitchOffset;
+    }
+
+    for (i = 0; i < 3; ++i) {
+      chorus->work.src.posHi = chorus->work.currentPosHi;
+      chorus->work.src.posLo = chorus->work.currentPosLo;
+      switch (i) {
+      case 0:
+        chorus->work.src.smpBase = chorus->work.lastLeft[0];
+        chorus->work.src.dest = info->data.bufferUpdate.left;
+        chorus->work.src.old = chorus->work.oldLeft;
+        break;
+      case 1:
+        chorus->work.src.smpBase = chorus->work.lastRight[0];
+        chorus->work.src.dest = info->data.bufferUpdate.right;
+        chorus->work.src.old = chorus->work.oldRight;
+        break;
+      case 2:
+        chorus->work.src.smpBase = chorus->work.lastSur[0];
+        chorus->work.src.dest = info->data.bufferUpdate.surround;
+        chorus->work.src.old = chorus->work.oldSur;
+        break;
+      }
+
+      switch (chorus->work.src.pitchHi) {
+      case 0:
+        do_src1(&chorus->work.src);
+        break;
+      case 1:
+        do_src2(&chorus->work.src);
+        break;
+      }
+    }
+
+    chorus->work.currentPosHi = chorus->work.src.posHi % 480;
+    chorus->work.currentPosLo = chorus->work.src.posLo;
+    chorus->work.currentLast = currLast;
+    break;
+  case SND_AUX_REASON_PARAMETERUPDATE:
+    break;
+  default:
+    ASSERT(FALSE);
+    break;
+  }
+}
+
+bool sndAuxCallbackUpdateSettingsChorus(SND_AUX_CHORUS* ch) {
+  ch->work.currentPosHi = 0x140 - ((ch->baseDelay - 5) << 5);
+  ch->work.currentPosLo = 0;
+  ch->work.currentPosHi = (ch->work.currentPosHi + (ch->work.currentLast - 1) * 0xa0) % 0x1e0;
+  ch->work.pitchOffsetPeriod = (ch->period / 5) + 1 & ~1;
+  ch->work.pitchOffsetPeriodCount = (u32)ch->work.pitchOffsetPeriod >> 1;
+  ch->work.pitchOffset = (ch->variation << 16) / (ch->work.pitchOffsetPeriod * 5);
+  return TRUE;
+}
+
+bool sndAuxCallbackPrepareChorus(SND_AUX_CHORUS* chorus) {
+  u32 i;
+  bool ret;
+  s32* lastLeft;
+  s32* lastRight;
+  s32* lastSur;
+
+  chorus->work.lastLeft[0] = (s32*)salMalloc(0x1680);
+
+  if (chorus->work.lastLeft[0] != NULL) {
+    chorus->work.lastRight[0] = chorus->work.lastLeft[0] + 0x1e0;
+    chorus->work.lastSur[0] = chorus->work.lastRight[0] + 0x1e0;
+
+    for (i = 0; i < 3; ++i) {
+      chorus->work.lastLeft[i] = chorus->work.lastLeft[0] + i * 0xa0;
+      chorus->work.lastRight[i] = chorus->work.lastRight[0] + i * 0xa0;
+      chorus->work.lastSur[i] = chorus->work.lastSur[0] + i * 0xa0;
+    }
+
+    lastLeft = chorus->work.lastLeft[0];
+    lastRight = chorus->work.lastRight[0];
+    lastSur = chorus->work.lastSur[0];
+    for (i = 0; i < 0x140; i += 1) {
+      *lastLeft = 0;
+      ++lastLeft;
+      *lastRight = 0;
+      ++lastRight;
+      *lastSur = 0;
+      ++lastSur;
+    }
+
+    chorus->work.currentLast = 1;
+    chorus->work.oldLeft[3] = 0;
+    chorus->work.oldLeft[2] = 0;
+    chorus->work.oldLeft[1] = 0;
+    chorus->work.oldLeft[0] = 0;
+    chorus->work.oldRight[3] = 0;
+    chorus->work.oldRight[2] = 0;
+    chorus->work.oldRight[1] = 0;
+    chorus->work.oldRight[0] = 0;
+    chorus->work.oldSur[3] = 0;
+    chorus->work.oldSur[2] = 0;
+    chorus->work.oldSur[1] = 0;
+    chorus->work.oldSur[0] = 0;
+
+    chorus->work.src.trigger = 480;
+    chorus->work.src.target = 0;
+    ret = sndAuxCallbackUpdateSettingsChorus(chorus);
+  } else {
+    ret = FALSE;
+  }
+  return ret;
+}
+
+bool sndAuxCallbackShutdownChorus(SND_AUX_CHORUS* ch) {
+  salFree(ch->work.lastLeft[0]);
+  return TRUE;
+}
diff --git a/src/musyx/reverb.c b/src/musyx/reverb.c
index 96dc57f4..4bdfd29b 100644
--- a/src/musyx/reverb.c
+++ b/src/musyx/reverb.c
@@ -34,17 +34,17 @@ bool ReverbHICreate(_SND_REVHI_WORK* rev, f32 coloration, f32 time, f32 mix, f32
 
   for (i = 0; i < 3; ++i) {
     for (j = 0; j < 3; ++j) {
-      DLcreate(&rev->C[i], lens[j] + 2);
-      DLsetdelay(&rev->C[i], lens[j]);
+      DLcreate(&rev->C[j + i], lens[j] + 2);
+      DLsetdelay(&rev->C[j + i], lens[j]);
       rev->combCoef[j + i * 3] = pow(10.f, (lens[j] * -3) / (32000.f * time));
     }
 
     for (j = 0; j < 2; ++j) {
-      DLcreate(&rev->AP[i], lens[j + 3] + 2);
-      DLsetdelay(&rev->AP[i], lens[j + 3]);
+      DLcreate(&rev->AP[j + i], lens[j + 3] + 2);
+      DLsetdelay(&rev->AP[j + i], lens[j + 3]);
     }
-    DLcreate(&rev->AP[i], lens[i + 5] + 2);
-    DLsetdelay(&rev->AP[i], lens[i + 5]);
+    DLcreate(&rev->AP[i + 2], lens[i + 5] + 2);
+    DLsetdelay(&rev->AP[i + 2], lens[i + 5]);
     rev->lpLastout[i] = 0.f;
   }
 
@@ -74,11 +74,32 @@ bool ReverbHICreate(_SND_REVHI_WORK* rev, f32 coloration, f32 time, f32 mix, f32
 
   return TRUE;
 }
-void DoCrossTalk() {}
 
-void HandleReverb_0() {}
+static void DoCrossTalk(s32* a, s32* b, f32 start, f32 end) {}
 
-void ReverbHICallback() {}
+static void HandleReverb(s32*, SND_AUX_REVERBHI* rev, s32) {}
+
+#pragma dont_inline on
+void ReverbHICallback(s32* left, s32* right, s32* surround, SND_AUX_REVERBHI* rev) {
+  u8 i;
+  for (i = 0; i < 3; ++i) {
+    switch (i) {
+    case 0:
+      if (rev->rv.crosstalk != 0.f) {
+        DoCrossTalk(left, right, 0.5f * rev->rv.crosstalk, 1.f - (0.5f * rev->rv.crosstalk));
+      }
+      HandleReverb(left, rev, 0);
+      break;
+    case 1:
+      HandleReverb(right, rev, 1);
+      break;
+    case 2:
+      HandleReverb(surround, rev, 2);
+      break;
+    }
+  }
+}
+#pragma dont_inline reset
 
 void ReverbHIFree(_SND_REVHI_WORK* rv) {
   u8 i;
diff --git a/src/musyx/reverb_fx.c b/src/musyx/reverb_fx.c
index 118d93b9..2e8eaac7 100644
--- a/src/musyx/reverb_fx.c
+++ b/src/musyx/reverb_fx.c
@@ -15,13 +15,16 @@
 extern bool ReverbHICreate(_SND_REVHI_WORK* rev, f32 coloration, f32 time, f32 mix, f32 damping,
                            f32 preDelay, f32 crosstalk);
 extern void ReverbHIFree(_SND_REVHI_WORK* rev);
+extern void ReverbHIModify(_SND_REVHI_WORK* rev, f32 coloration, f32 time, f32 mix, f32 damping,
+                           f32 preDelay, f32 crosstalk);
+extern void ReverbHICallback(s32* left, s32* right, s32* surround, SND_AUX_REVERBHI* rev);
 
 void sndAuxCallbackReverbHI(u8 reason, SND_AUX_INFO* info, void* user) {
   switch (reason) {
   case SND_AUX_REASON_BUFFERUPDATE:
     if (((SND_AUX_REVERBHI*)user)->tempDisableFX == 0) {
       ReverbHICallback(info->data.bufferUpdate.left, info->data.bufferUpdate.right,
-                       info->data.bufferUpdate.surround, user);
+                       info->data.bufferUpdate.surround, (SND_AUX_REVERBHI*)user);
     }
   case SND_AUX_REASON_PARAMETERUPDATE:
     break;
@@ -31,8 +34,16 @@ void sndAuxCallbackReverbHI(u8 reason, SND_AUX_INFO* info, void* user) {
   }
 }
 
+bool sndAuxCallbackUpdateSettingsReverbHI(SND_AUX_REVERBHI* rev) {
+  rev->tempDisableFX = TRUE;
+  ReverbHIModify(&rev->rv, rev->coloration, rev->time, rev->mix, rev->damping, rev->preDelay,
+                 rev->crosstalk);
+  rev->tempDisableFX = FALSE;
+  return TRUE;
+}
+
 bool sndAuxCallbackPrepareReverbHI(SND_AUX_REVERBHI* rev) {
-  rev->tempDisableFX = 0;
+  rev->tempDisableFX = FALSE;
   return ReverbHICreate(&rev->rv, rev->coloration, rev->time, rev->mix, rev->damping, rev->preDelay,
                         rev->crosstalk);
 }
@@ -41,8 +52,3 @@ bool sndAuxCallbackShutdownReverbHI(SND_AUX_REVERBHI* rev) {
   ReverbHIFree(&rev->rv);
   return TRUE;
 }
-
-bool sndAuxCallbackUpdateSettingsReverbHI(SND_AUX_REVERBHI* rev) {
-  /* not in MP */
-  return FALSE;
-}
diff --git a/src/musyx/snd_init.c b/src/musyx/snd_init.c
index 76a67a8d..9f83801c 100644
--- a/src/musyx/snd_init.c
+++ b/src/musyx/snd_init.c
@@ -1,11 +1,6 @@
 #include "musyx/musyx_priv.h"
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/* TODO: Move these to a more approprate location */
-
+//#define _DEBUG
+#include "musyx/assert.h"
 
 s32 DoInit(u32 rate, u32 aramSize, u8 voices, u32 flags) {
   dataInitStack();
@@ -54,6 +49,9 @@ void sndQuit() {
   sndActive = 0;
 }
 
-#ifdef __cplusplus
+void sndSetMaxVoices(u8 music, u8 sfx) {
+  ASSERT_MSG(music > synthInfo.voices, "Music voices are above maximum voice number.");
+  ASSERT_MSG(sfx > synthInfo.voices, "Sfx voices are above maximum voice number.");
+  synthInfo.music = music;
+  synthInfo.sfx = sfx;
 }
-#endif
diff --git a/src/musyx/snd_math.c b/src/musyx/snd_math.c
index f31c94d3..7ac63567 100644
--- a/src/musyx/snd_math.c
+++ b/src/musyx/snd_math.c
@@ -21,4 +21,166 @@ void salCrossProduct(SND_FVECTOR* out, const SND_FVECTOR* a, const SND_FVECTOR*
   out->z = (a->x * b->y) - (a->y * b->x);
 }
 
-void salInvertMatrix(SND_FMATRIX* out, const SND_FMATRIX* in) { out->t[0] = 1.f; }
+#if NONMATCHING
+void salInvertMatrix(SND_FMATRIX* out, const SND_FMATRIX* in) {
+    float fVar1;
+    float fVar2;
+    float fVar3;
+    float fVar4;
+
+    fVar1 = in->m[1][1] * in->m[2][2] - in->m[2][1] * in->m[1][2];
+    fVar4 = -(in->m[1][0] * in->m[2][2] - in->m[2][0] * in->m[1][2]);
+    fVar2 = in->m[1][0] * in->m[2][1] - in->m[2][0] * in->m[1][1];
+    fVar3 = 1.f / (in->m[0][2] * fVar2 + in->m[0][0] * fVar1 + in->m[0][1] * fVar4);
+    out->m[0][0] = fVar3 * fVar1;
+    out->m[1][0] = fVar3 * fVar4;
+    out->m[2][0] = fVar3 * fVar2;
+    out->m[0][1] = -fVar3 * (in->m[0][1] * in->m[2][2] - in->m[2][1] * in->m[0][2]);
+    out->m[1][1] = fVar3 * (in->m[0][0] * in->m[2][2] - in->m[2][0] * in->m[0][2]);
+    out->m[2][1] = -fVar3 * (in->m[0][0] * in->m[2][1] - in->m[2][0] * in->m[0][1]);
+    out->m[0][2] = fVar3 * (in->m[0][1] * in->m[1][2] - in->m[1][1] * in->m[0][2]);
+    out->m[1][2] = -fVar3 * (in->m[0][0] * in->m[1][2] - in->m[1][0] * in->m[0][2]);
+    out->m[2][2] = fVar3 * (in->m[0][0] * in->m[1][1] - in->m[1][0] * in->m[0][1]);
+    out->t[0] = (-in->t[0] * out->m[0][0] - in->t[1] * out->m[0][1]) - in->t[2] * out->m[0][2];
+    out->t[1] = (-in->t[0] * out->m[1][0] - in->t[1] * out->m[1][1]) - in->t[2] * out->m[1][2];
+    out->t[2] = (-in->t[0] * out->m[2][0] - in->t[1] * out->m[2][1]) - in->t[2] * out->m[2][2];
+}
+#else
+/* clang-format off */
+#pragma push
+#pragma optimization_level 0
+#pragma optimizewithasm off
+const float one = 1.f;
+asm void salInvertMatrix(SND_FMATRIX* out, const SND_FMATRIX* in) {
+  nofralloc
+  lfs f5, 0x20(r4)
+  lfs f10, 0xc(r4)
+  lfs f0, 0x14(r4)
+  lfs f6, 0x1c(r4)
+  fmuls f3, f10, f5
+  lfs f9, 0x18(r4)
+  lfs f8, 0x10(r4)
+  fmuls f4, f6, f0
+  fmuls f2, f9, f0
+  lfs f1, 0(r4)
+  fmuls f7, f8, f5
+  lfs f0, 4(r4)
+  fmuls f5, f10, f6
+  fsubs f6, f3, f2
+  fsubs f7, f7, f4
+  lfs f2, 8(r4)
+  fmuls f4, f9, f8
+  lfs f3, one
+  fneg f6, f6
+  fmuls f1, f1, f7
+  fsubs f4, f5, f4
+  fmuls f0, f0, f6
+  fmuls f2, f2, f4
+  fadds f0, f1, f0
+  fadds f0, f2, f0
+  fdivs f1, f3, f0
+  fmuls f0, f1, f7
+  fmuls f3, f1, f6
+  fmuls f2, f1, f4
+  stfs f0, 0(r3)
+  fneg f0, f1
+  stfs f3, 0xc(r3)
+  stfs f2, 0x18(r3)
+  lfs f5, 4(r4)
+  lfs f4, 0x20(r4)
+  lfs f3, 0x1c(r4)
+  lfs f2, 8(r4)
+  fmuls f4, f5, f4
+  fmuls f2, f3, f2
+  fsubs f2, f4, f2
+  fmuls f2, f0, f2
+  stfs f2, 4(r3)
+  lfs f5, 0(r4)
+  lfs f4, 0x20(r4)
+  lfs f3, 0x18(r4)
+  lfs f2, 8(r4)
+  fmuls f4, f5, f4
+  fmuls f2, f3, f2
+  fsubs f2, f4, f2
+  fmuls f2, f1, f2
+  stfs f2, 0x10(r3)
+  lfs f5, 0(r4)
+  lfs f4, 0x1c(r4)
+  lfs f3, 0x18(r4)
+  lfs f2, 4(r4)
+  fmuls f4, f5, f4
+  fmuls f2, f3, f2
+  fsubs f2, f4, f2
+  fmuls f2, f0, f2
+  stfs f2, 0x1c(r3)
+  lfs f5, 4(r4)
+  lfs f4, 0x14(r4)
+  lfs f3, 0x10(r4)
+  lfs f2, 8(r4)
+  fmuls f4, f5, f4
+  fmuls f2, f3, f2
+  fsubs f2, f4, f2
+  fmuls f2, f1, f2
+  stfs f2, 8(r3)
+  lfs f5, 0(r4)
+  lfs f4, 0x14(r4)
+  lfs f3, 0xc(r4)
+  lfs f2, 8(r4)
+  fmuls f4, f5, f4
+  fmuls f2, f3, f2
+  fsubs f2, f4, f2
+  fmuls f0, f0, f2
+  stfs f0, 0x14(r3)
+  lfs f4, 0(r4)
+  lfs f3, 0x10(r4)
+  lfs f2, 0xc(r4)
+  lfs f0, 4(r4)
+  fmuls f3, f4, f3
+  fmuls f0, f2, f0
+  fsubs f0, f3, f0
+  fmuls f0, f1, f0
+  stfs f0, 0x20(r3)
+  lfs f0, 0x24(r4)
+  lfs f4, 0(r3)
+  fneg f5, f0
+  lfs f3, 0x28(r4)
+  lfs f2, 4(r3)
+  lfs f1, 0x2c(r4)
+  lfs f0, 8(r3)
+  fmuls f4, f5, f4
+  fmuls f2, f3, f2
+  fmuls f0, f1, f0
+  fsubs f1, f4, f2
+  fsubs f0, f1, f0
+  stfs f0, 0x24(r3)
+  lfs f0, 0x24(r4)
+  lfs f4, 0xc(r3)
+  fneg f5, f0
+  lfs f3, 0x28(r4)
+  lfs f2, 0x10(r3)
+  lfs f1, 0x2c(r4)
+  lfs f0, 0x14(r3)
+  fmuls f4, f5, f4
+  fmuls f2, f3, f2
+  fmuls f0, f1, f0
+  fsubs f1, f4, f2
+  fsubs f0, f1, f0
+  stfs f0, 0x28(r3)
+  lfs f1, 0x24(r4)
+  lfs f0, 0x18(r3)
+  fneg f4, f1
+  lfs f3, 0x28(r4)
+  lfs f2, 0x1c(r3)
+  lfs f1, 0x2c(r4)
+  fmuls f4, f4, f0
+  lfs f0, 0x20(r3)
+  fmuls f2, f3, f2
+  fmuls f0, f1, f0
+  fsubs f1, f4, f2
+  fsubs f0, f1, f0
+  stfs f0, 0x2c(r3)
+  blr
+}
+#pragma pop
+/* clang-format on */
+#endif
diff --git a/src/musyx/snd_midictrl.c b/src/musyx/snd_midictrl.c
new file mode 100644
index 00000000..fdc904a3
--- /dev/null
+++ b/src/musyx/snd_midictrl.c
@@ -0,0 +1,50 @@
+#include "musyx/assert.h"
+#include "musyx/musyx_priv.h"
+#define SYNTH_FX_MIDISET 0xFF
+
+u32 inpGlobalMIDIDirtyFlags[8][16];
+s32 midi_ctrl;
+
+inline bool GetGlobalFlagSet(u8 chan, u8 midiSet, s32 flag) {
+  return (flag & inpGlobalMIDIDirtyFlags[midiSet][chan]) != 0;
+}
+
+void inpResetGlobalMIDIDirtyFlags() {
+  u32 i, j;
+  for (i = 0; i < 8; ++i) {
+    for (j = 0; j < 16; ++j) {
+      inpGlobalMIDIDirtyFlags[i][j] = 0xFF;
+    }
+  }
+}
+
+bool inpResetGlobalMIDIDirtyFlag(u8 chan, u8 midiSet, s32 flag) {
+  // ASSERT(midiSet!=SYNTH_FX_MIDISET);
+  bool ret = GetGlobalFlagSet(chan, midiSet, flag);
+  if (ret) {
+    inpGlobalMIDIDirtyFlags[midiSet][chan] &= ~flag;
+  }
+  return ret;
+}
+
+void inpSetGlobalMIDIDirtyFlag(u8 chan, u8 midiSet, s32 flag) {
+  // ASSERT(midiSet!=SYNTH_FX_MIDISET);
+  inpGlobalMIDIDirtyFlags[midiSet][chan] |= flag;
+}
+
+void inpSetRPNHi(u8 a, u8 b, u8 c) {
+
+}
+
+void inpSetRPNLo(u8 a, u8 b, u8 c) {
+
+}
+
+void inpSetRPNDec(u8 a, u8 b) {
+  
+}
+
+
+void inpSetRPNInc(u8 a, u8 b) {
+  
+}