diff --git a/src/samples/ghhb_game.h b/src/samples/ghhb_game.h
index ea3d3b7..45030e0 100644
--- a/src/samples/ghhb_game.h
+++ b/src/samples/ghhb_game.h
@@ -16,6 +16,9 @@ namespace
 {
 constexpr int LANE_COUNT = 12;
 constexpr int OCTAVE_COUNT = 3;
+constexpr int MIDI_LANE_MIN = 48;
+constexpr int MIDI_LANE_MAX = 83;
+constexpr int MIDI_LANE_COUNT = MIDI_LANE_MAX - MIDI_LANE_MIN + 1;
 constexpr int MAX_GAMEPADS = 4;
 constexpr int MAX_INSTRUMENT_TYPES = MAX_GAMEPADS;
 constexpr float RECEPTOR_HEIGHT = 150.0f;
@@ -25,7 +28,7 @@ constexpr float SCROLL_PX_PER_SEC = 350.0f;
 constexpr float LEAD_OFFSET_SECONDS = 3.0f;
 constexpr float GLYPH_HEIGHT_FRACTION_OF_LANE = 0.5f;
 constexpr float MIN_SUSTAIN_FALLBACK_SEC = 0.05f;
-constexpr float MIN_GLYPH_DURATION_SEC = 0.05f;
+constexpr float MIN_GLYPH_DURATION_SEC = 0.1f;
 
 const int GAMEPAD_BUTTONS[LANE_COUNT] = {
     GAMEPAD_BUTTON_LEFT_FACE_LEFT, // Left
@@ -86,7 +89,8 @@ const float INSTRUMENT_VOLUME[MAX_INSTRUMENT_TYPES] = {
     0.7f
 };
 
-const char* const INSTRUMENT_LANE_WAV[MAX_INSTRUMENT_TYPES][LANE_COUNT * OCTAVE_COUNT] {
+/* Index i = MIDI note (48 + i); notes outside [48, 83] are not rendered. */
+const char* const INSTRUMENT_LANE_WAV[MAX_INSTRUMENT_TYPES][MIDI_LANE_COUNT] {
     { // Instrument 0 - Synth
         "assets/sounds/snes_synth/snes_synth_048.wav", "assets/sounds/snes_synth/snes_synth_049.wav",
         "assets/sounds/snes_synth/snes_synth_050.wav", "assets/sounds/snes_synth/snes_synth_051.wav",
@@ -241,7 +245,7 @@ std::vector<Glyph> chart_from_song(const Song& song, int track_override)
     std::vector<std::pair<int, const Note*>> timed_notes;
     for (const Note& note : track.notes)
     {
-        if (note.midi >= 0 && note.midi <= 127)
+        if (note.midi >= MIDI_LANE_MIN && note.midi <= MIDI_LANE_MAX)
             timed_notes.push_back({note.ticks, &note});
     }
     std::sort(timed_notes.begin(), timed_notes.end(),
@@ -257,8 +261,9 @@ std::vector<Glyph> chart_from_song(const Song& song, int track_override)
         const Note& note = *pair.second;
         float time_sec = note.ticks / ticks_per_sec;  // This is now the BOTTOM time
         float duration_sec = note.duration_ticks / ticks_per_sec;
-        int lane = note.midi % LANE_COUNT;
-        int octave = note.midi % (LANE_COUNT * OCTAVE_COUNT);
+        int wav_index = note.midi - MIDI_LANE_MIN;
+        int lane = wav_index % LANE_COUNT;
+        int octave = wav_index;
         int instrument_slot = note_index % MAX_INSTRUMENT_TYPES;
 
         // Log original glyph timing (time is bottom, time + duration is top)
@@ -352,8 +357,8 @@ public:
     float lane_width = 0.0f;
     float screen_width = 0.0f;
     float screen_height = 0.0f;
-    Sound note_sounds[MAX_INSTRUMENT_TYPES][LANE_COUNT * OCTAVE_COUNT] = {{0}};
-    bool note_sounds_loaded[MAX_INSTRUMENT_TYPES][LANE_COUNT * OCTAVE_COUNT] = {{false}};
+    Sound note_sounds[MAX_INSTRUMENT_TYPES][MIDI_LANE_COUNT] = {{0}};
+    bool note_sounds_loaded[MAX_INSTRUMENT_TYPES][MIDI_LANE_COUNT] = {{false}};
     std::deque<Sound> note_sounds_playing[LANE_COUNT][MAX_INSTRUMENT_TYPES];
     static constexpr float PRESS_FLASH_DURATION = 0.12f;
     float press_flash_timer[LANE_COUNT] = {0};
@@ -420,7 +425,7 @@ public:
         }
         for (int slot = 0; slot < MAX_INSTRUMENT_TYPES; slot++)
         {
-            for (int lane = 0; lane < LANE_COUNT * OCTAVE_COUNT; lane++)
+            for (int lane = 0; lane < MIDI_LANE_COUNT; lane++)
             {
                 if (note_sounds_loaded[slot][lane])
                 {
@@ -441,7 +446,7 @@ public:
         update_layout();
         for (int slot = 0; slot < MAX_INSTRUMENT_TYPES; slot++)
         {
-            for (int lane = 0; lane < LANE_COUNT * OCTAVE_COUNT; lane++)
+            for (int lane = 0; lane < MIDI_LANE_COUNT; lane++)
             {
                 const char* path = INSTRUMENT_LANE_WAV[slot][lane];
                 if (FileExists(path))