Melodies in octaves – balance of sound between the octaves
March 29, 2018
Summary: How to ‘de-muddify’ notes in octaves
For me, one of the most difficult sonic tasks at the piano is to balance two notes if they are exactly one octave apart. If a melody sounds in two octaves at once, it is usually at this distance of one octave. In spite of all my attempts, the resulting sound is not a clear blending, but contains elements of diffuseness and mutual interference. I never have considered this sound acceptable.
Interestingly, this problem disappears if I separate the two notes by exactly two octaves. The way the overtones of the two notes combine in this case creates a pristine and crystalline acoustical effect, noticeably different than the muddiness of the single octave. For organists it is the same as the difference of combining the principal 8 foot and 2 foot stops as against the 8 and 4 foot stops.
There are three things that I can do to help clarify the sound in the cases where the composer does have a melody in notes one octave apart. How to de-muddify:
1. Have the duration of the notes in the lower octave be slightly shorter than those in the upper octave. This will overcome the natural tendency for lower pitches to seem to move more slowly than higher pitches. There will be a barely detectable silence in the sound from the lower octave at end of each of its notes, before the next notes of the melody begin simultaneously.
2. I can play around with the relative loudness of the two notes. Depending on the musical context, there will be cases when the lower notes can be slightly louder than the upper, and other cases when the opposite seems best. This is like “orchestrating” the given passage.
3. Consider the note an octave higher as being simply the first overtone of the lower note. In this way we can hear the upper note as being already contained in the lower note.