         return tuning
     }
     
-    // - Tuning Pure -
-   
-    // 純正律（長調）centによる計算
-    // 基準ピッチとの周波数比r = 2^(n/12 + m/1200)
-    // n:音程差（半音であれば1） m:平均律とのズレ(cent)
+    // Tuning Pure Major
+    // Frequency ratio for standard pitch: r = 2^(n/12 + m/1200)
+    // n: Interval difference (1 for semitone)
+    // m: Difference from equal temperament (in cent)
     private class func centOffsetsForPureMajor() -> [Float] {
         let offset1:  Float =   0.0 / 1200.0
         let offset2:  Float = -29.3 / 1200.0

        }
        return tuning
    }
  
    /*
    * あるオクターブに対する12音をtuningBaseを整数倍することで生成
    */
    private class func generateForOctave(octave: Int, tuningBase: [SoundName: Float]) -> [SoundName: Float] {
        var tuningForCurrentOctave = [SoundName: Float]()
        for key in tuningBase.keys {

    // => http://ja.wikipedia.org/wiki/%E9%9F%B3%E5%90%8D%E3%83%BB%E9%9A%8E%E5%90%8D%E8%A1%A8%E8%A8%98
    private class func generateEqualBase(pitch: Float, transpositionNote: SoundName) -> [SoundName: Float] {
        
        // Frequencies if transpositionNote = C
        var baseTuning: [Float] = [
            self.frequencyForPitch(pitch, order: 3.0)  / 16.0,  // Cのkey
            self.frequencyForPitch(pitch, order: 4.0)  / 16.0,  // Db
