/// <summary>
/// Add one chord and its duration to harmony.
/// </summary>
/// <param name="chordName">Name of chord played</param>
/// <param name="duration">Length of chord in milliseconds</param>
public void AddChord(ChordName chordName, long duration)
{
Chord chord = new Chord(scale, chordName);
harmonyEpochs.Add(Epoch.CreateEpoch(duration, chord.Tones));
}