diff --git a/source/Cosmos.System2/PCSpeaker.cs b/source/Cosmos.System2/PCSpeaker.cs
index 47a2c5af6..467a2bd59 100644
--- a/source/Cosmos.System2/PCSpeaker.cs
+++ b/source/Cosmos.System2/PCSpeaker.cs
@@ -54,64 +54,89 @@ namespace Cosmos.System
     /// </summary>
     public enum Notes
     {
-         A0 = 28, // Exactly 27.500
-         AS0 = 29,
-         B0 = 31,
-         C1 = 33,
-         CS1 = 35,
-         D1 = 37,
-         DS1 = 39,
-         E1 = 41,
-         F1 = 44,
-         FS1 = 46,
-         G1 = 49,
-         GS1 = 52,
-         A1 = 55, // Exactly 55.000hz
-         AS1 = 58,
-         B1 = 62,
-         C2 = 65,
-         CS2 = 69,
-         D2 = 73,
-         DS2 = 78,
-         E2 = 82,
-         F2 = 87,
-         FS2 = 92,
-         G2 = 98,
-         GS2 = 104,
-         A2 = 110, // Exactly 110.000hz
-         AS2 = 117,
-         B2 = 123,
-         C3 = 131,
-         CS3 = 139,
-         D3 = 147,
-         DS3 = 156,
-         E3 = 165,
-         F3 = 175,
-         FS3 = 185,
-         G3 = 196,
-         GS3 = 208,
-         A3 = 220, // Exactly 220.000hz
-         AS3 = 233,
-         B3 = 247,
-         C4 = 262,
-         CS4 = 277,
-         D4 = 294,
-         DS4 = 311,
-         E4 = 330,
-         F4 = 349,
-         FS4 = 370,
-         G4 = 392,
-         GS4 = 415,
-         A4 = 440, // Exactly 440.000hz | Concert Pitch
-         AS4 = 466,
-         B4 = 494,
-         C5 = 523,
-         CS5 = 554,
-         D5 = 587,
-         DS5 = 622,
-         E5 = 659,
+        A0 = 28, // Exactly 27.500
+        AS0 = 29,
+        B0 = 31,
 
-         Default = 800,
+        C1 = 33,
+        CS1 = 35,
+        D1 = 37,
+        DS1 = 39,
+        E1 = 41,
+        F1 = 44,
+        FS1 = 46,
+        G1 = 49,
+        GS1 = 52,
+        A1 = 55, // Exactly 55.000hz
+        AS1 = 58,
+        B1 = 62,
+
+        C2 = 65,
+        CS2 = 69,
+        D2 = 73,
+        DS2 = 78,
+        E2 = 82,
+        F2 = 87,
+        FS2 = 92,
+        G2 = 98,
+        GS2 = 104,
+        A2 = 110, // Exactly 110.000hz
+        AS2 = 117,
+        B2 = 123,
+
+        C3 = 131,
+        CS3 = 139,
+        D3 = 147,
+        DS3 = 156,
+        E3 = 165,
+        F3 = 175,
+        FS3 = 185,
+        G3 = 196,
+        GS3 = 208,
+        A3 = 220, // Exactly 220.000hz
+        AS3 = 233,
+        B3 = 247,
+
+        C4 = 262,
+        CS4 = 277,
+        D4 = 294,
+        DS4 = 311,
+        E4 = 330,
+        F4 = 349,
+        FS4 = 370,
+        G4 = 392,
+        GS4 = 415,
+        A4 = 440, // Exactly 440.000hz | Concert Pitch
+        AS4 = 466,
+        B4 = 494,
+
+        C5 = 523,
+        CS5 = 554,
+        D5 = 587,
+        DS5 = 622,
+        E5 = 659,
+        F5 = 698,
+        FS5 = 739,
+        G5 = 783,
+        GS5 = 830,
+        A5 = 880, // Exactly 880.000hz
+        AS5 = 932,
+        B5 = 987,
+
+        C6 = 1046,
+        CS6 = 1108,
+        D6 = 1174,
+        DS6 = 1244,
+        E6 = 1318,
+        F6 = 1396,
+        FS6 = 1479,
+        G6 = 1567,
+        GS6 = 1661,
+        A6 = 1760, // Exactly 1760.000hz
+        AS6 = 1864,
+        B6 = 1975,
+
+        Default = 800,
     }
 
     // TODO: continue exception list, once HAL is documented.