diff --git a/BizHawk.Emulation.DiscSystem/BizHawk.Emulation.DiscSystem.csproj b/BizHawk.Emulation.DiscSystem/BizHawk.Emulation.DiscSystem.csproj
index 6017f778f6..af11ed18f6 100644
--- a/BizHawk.Emulation.DiscSystem/BizHawk.Emulation.DiscSystem.csproj
+++ b/BizHawk.Emulation.DiscSystem/BizHawk.Emulation.DiscSystem.csproj
@@ -74,6 +74,7 @@
     <Compile Include="GPL_ECM.cs" />
     <Compile Include="M3U_file.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
+    <Compile Include="SBI_format.cs" />
     <Compile Include="SectorInterfaces.cs" />
     <Compile Include="Subcode.cs" />
     <Compile Include="TOC\DiscStructure.cs" />
diff --git a/BizHawk.Emulation.DiscSystem/Disc.cs b/BizHawk.Emulation.DiscSystem/Disc.cs
index 371f6d557d..ddc5557304 100644
--- a/BizHawk.Emulation.DiscSystem/Disc.cs
+++ b/BizHawk.Emulation.DiscSystem/Disc.cs
@@ -66,6 +66,11 @@ namespace BizHawk.Emulation.DiscSystem
 {
 	public partial class Disc : IDisposable
 	{
+		/// <summary>
+		/// Free-form optional memos about the disc
+		/// </summary>
+		public Dictionary<string, object> Memos = new Dictionary<string, object>();
+
 		/// <summary>
 		/// The raw TOC entries found in the lead-in track.
 		/// </summary>
@@ -204,9 +209,19 @@ FILE ""xarp.barp.marp.farp"" BINARY
 		{
 			var ret = new Disc();
 			ret.FromCuePathInternal(cuePath, prefs);
+
 			ret.Structure.Synthesize_TOCPointsFromSessions();
 			ret.Synthesize_SubcodeFromStructure();
 			ret.Synthesize_TOCRawFromStructure();
+
+			//try loading SBI. make sure its done after the subcode is synthesized!
+			string sbiPath = Path.ChangeExtension(cuePath, "sbi");
+			if (File.Exists(sbiPath) && SBI_Format.QuickCheckISSBI(sbiPath))
+			{
+				var sbi = new SBI_Format().LoadSBIPath(sbiPath);
+				ret.ApplySBI(sbi);
+			}
+
 			return ret;
 		}
 
@@ -251,6 +266,33 @@ FILE ""xarp.barp.marp.farp"" BINARY
 			TOCRaw.LeadoutTimestamp = new Timestamp(lastEnd);
 		}
 
+		/// <summary>
+		/// applies an SBI file to the disc
+		/// </summary>
+		public void ApplySBI(SBI_Format.SBIFile sbi)
+		{
+			//save this, it's small, and we'll want it for disc processing a/b checks
+			Memos["sbi"] = sbi;
+
+			int n = sbi.ABAs.Count;
+			byte[] subcode = new byte[96];
+			int b=0;
+			for (int i = 0; i < n; i++)
+			{
+				int aba = sbi.ABAs[i];
+				var oldSubcode = this.Sectors[aba].SubcodeSector;
+				oldSubcode.ReadSubcodeDeinterleaved(subcode, 0);
+				for (int j = 0; j < 12; j++)
+				{
+					short patch = sbi.subq[b++];
+					if (patch == -1) continue;
+					else subcode[12 + j] = (byte)patch;
+				}
+				var bss = new BufferedSubcodeSector();
+				Sectors[aba].SubcodeSector = BufferedSubcodeSector.CloneFromBytesDeinterleaved(subcode);
+			}
+		}
+
 		/// <summary>
 		/// Creates the subcode (really, just subchannel Q) for this disc from its current TOC.
 		/// Depends on the TOCPoints existing in the structure
@@ -283,10 +325,6 @@ FILE ""xarp.barp.marp.farp"" BINARY
 				}
 				var dp = Structure.Points[dpIndex];
 
-				if (aba == 4903 + 150)
-				{
-					int zzz = 9;
-				}
 
 				var se = Sectors[aba];
 
@@ -366,8 +404,14 @@ FILE ""xarp.barp.marp.farp"" BINARY
 			return new BCD2 {DecimalValue = d};
 		}
 
+		public static int BCDToInt(byte n)
+		{
+			var bcd = new BCD2();
+			bcd.BCDValue = n;
+			return bcd.DecimalValue;
+		}
 
-		static byte IntToBCD(int n)
+		public static byte IntToBCD(int n)
 		{
 			int ones;
 			int tens = Math.DivRem(n, 10, out ones);
diff --git a/BizHawk.Emulation.DiscSystem/SBI_format.cs b/BizHawk.Emulation.DiscSystem/SBI_format.cs
new file mode 100644
index 0000000000..7f31b45765
--- /dev/null
+++ b/BizHawk.Emulation.DiscSystem/SBI_format.cs
@@ -0,0 +1,104 @@
+using System;
+using System.Text;
+using System.IO;
+using System.Collections.Generic;
+
+using BizHawk.Common.IOExtensions;
+
+namespace BizHawk.Emulation.DiscSystem
+{
+	public class SBI_Format
+	{
+		public class SBIParseException : Exception
+		{
+			public SBIParseException(string message) : base(message) { }
+		}
+
+		public class SBIFile
+		{
+			/// <summary>
+			/// a list of patched ABAs
+			/// </summary>
+			public List<int> ABAs = new List<int>();
+
+			/// <summary>
+			/// 12 values (Q subchannel data) for every patched ABA; -1 means unpatched
+			/// </summary>
+			public short[] subq;
+		}
+
+		/// <summary>
+		/// Does a cursory check to see if the file looks like an SBI
+		/// </summary>
+		public static bool QuickCheckISSBI(string path)
+		{
+			using (var fs = File.OpenRead(path))
+			{
+				BinaryReader br = new BinaryReader(fs);
+				string sig = br.ReadStringFixedAscii(4);
+				if (sig != "SBI\0")
+					return false;
+			}
+			return true;
+		}
+
+		/// <summary>
+		/// Loads an SBI file from the specified path
+		/// </summary>
+		public SBIFile LoadSBIPath(string path)
+		{
+			using(var fs = File.OpenRead(path))
+			{
+				BinaryReader br = new BinaryReader(fs);
+				string sig = br.ReadStringFixedAscii(4);
+				if (sig != "SBI\0")
+					throw new SBIParseException("Missing magic number");
+
+				SBIFile ret = new SBIFile();
+				List<short> bytes = new List<short>();
+
+				//read records until done
+				for (; ; )
+				{
+					//graceful end
+					if (fs.Position == fs.Length)
+						break;
+
+					if (fs.Position+4 > fs.Length) throw new SBIParseException("Broken record");
+					var m = BCD2.BCDToInt(br.ReadByte());
+					var s = BCD2.BCDToInt(br.ReadByte());
+					var f = BCD2.BCDToInt(br.ReadByte());
+					var ts = new Timestamp(m, s, f);
+					ret.ABAs.Add(ts.Sector);
+					int type = br.ReadByte();
+					switch (type)
+					{
+						case 1: //Q0..Q9
+							if (fs.Position + 10 > fs.Length) throw new SBIParseException("Broken record");
+							for (int i = 0; i <= 9; i++) bytes.Add(br.ReadByte());
+							for (int i = 10; i <= 11; i++) bytes.Add(-1);
+							break;
+						case 2: //Q3..Q5
+							if (fs.Position + 3 > fs.Length) throw new SBIParseException("Broken record");
+							for (int i = 0; i <= 2; i++) bytes.Add(-1);
+							for (int i = 3; i <= 5; i++) bytes.Add(br.ReadByte());
+							for (int i = 6; i <= 11; i++) bytes.Add(-1);
+							break;
+						case 3: //Q7..Q9
+							if (fs.Position + 3 > fs.Length) throw new SBIParseException("Broken record");
+							for (int i = 0; i <= 6; i++) bytes.Add(-1);
+							for (int i = 7; i <= 9; i++) bytes.Add(br.ReadByte());
+							for (int i = 10; i <= 11; i++) bytes.Add(-1);
+							break;
+						default:
+							throw new SBIParseException("Broken record");
+					}
+				}
+				
+				ret.subq = bytes.ToArray();
+				return ret;
+
+			}
+		}
+	}
+}
\ No newline at end of file
diff --git a/BizHawk.Emulation.DiscSystem/Subcode.cs b/BizHawk.Emulation.DiscSystem/Subcode.cs
index 7488b40da8..ec69b3eeba 100644
--- a/BizHawk.Emulation.DiscSystem/Subcode.cs
+++ b/BizHawk.Emulation.DiscSystem/Subcode.cs
@@ -108,7 +108,19 @@ namespace BizHawk.Emulation.DiscSystem
 			Buffer.BlockCopy(SubcodeDeinterleaved, number * 12, buffer, offset, 12);
 		}
 
-		public byte[] SubcodeDeinterleaved = new byte[96];
+		public BufferedSubcodeSector()
+		{
+			SubcodeDeinterleaved = new byte[96];
+		}
+
+		public static BufferedSubcodeSector CloneFromBytesDeinterleaved(byte[] buffer)
+		{
+			var ret = new BufferedSubcodeSector();
+			Buffer.BlockCopy(buffer, 0, ret.SubcodeDeinterleaved, 0, 96);
+			return ret;
+		}
+
+		public byte[] SubcodeDeinterleaved;
 	}
 
 	public class ZeroSubcodeSector : ISubcodeSector