diff --git a/tools/check_nspc.py b/tools/check_nspc.py
index 5a98851b..eb0e4675 100755
--- a/tools/check_nspc.py
+++ b/tools/check_nspc.py
@@ -80,12 +80,12 @@ def getNextBlockAddr(self):
       Range(0x5828, 0x6818, "  Song-specific tracker data", True),
     Range(0x6819, 0x6BFF, "Unused", allowUnused),
     Range(0x6C00, 0x6CE9, "Instrument table", True),
-      Range(0x6C00, 0x6C8F, "  Shared instruments (0..17h)", False),
-      Range(0x6C90, 0x6CE9, "  Song-specific instruments (18h..26h)", True),
+      Range(0x6C00, 0x6C83, "  Shared instruments (0..15h)", False),
+      Range(0x6C84, 0x6CE9, "  Song-specific instruments (16h..26h)", True),
     Range(0x6CEA, 0x6CFF, "Unused", allowUnused),
     Range(0x6D00, 0x6D9F, "Sample table", True),
-      Range(0x6D00, 0x6D5F, "  Shared sample table", False),
-      Range(0x6D60, 0x6D9F, "  Song-specific sample table", True),
+      Range(0x6D00, 0x6D57, "  Shared sample table", False),
+      Range(0x6D58, 0x6D9F, "  Song-specific sample table", True),
     Range(0x6DA0, 0x6DFF, "Unused", allowUnused),
     Range(0x6E00, 0xFFFF, "Sample data", True),
       Range(0x6E00, 0xB20F, "  Shared sample data", False),