Practicing With Drones
When using drones to practice intonation, there are some key things that you can learn to listen for in order to get the most out of your practice.
Much of what we think about as good or bad intonation has to do with resultant pitch. Any two pitches played simultaneously will produce a resultant pitch. And resultant pitches can interact with the original pitches to create more resultant pitches. This is why we often hear more than just the played notes in a chord.
The frequency of the resultant pitch will always be equal to the difference between the two sounded notes. So, if two notes are played, one vibrating at 500 Hz and one at 300 Hz, the resultant pitch they produce will vibrate at 200 Hz.
Sometimes the resultant pitch can be heard as “beats” between your note and the drone. Beats are the result of two sound waves that are very close together but do not quite line up with each other, causing a rhythmic pulsing in the sound that our ears interpret as a discord. This is what we typically think of as out of tune. You can practice listening for the beats by playing in unison with a drone and very slowly bending your pitch up and down. The closer you get to being perfectly in tune, the slower the beats get until they disappear. The further away you get from matching, the faster the beats occur.
Listen to this example of an A440 being played against an A442. Because the difference between these two pitches is 2 Hz, you can clearly hear 2 “beats” every second.
Resultant pitches can also be quite harmonious when they line up correctly. For example, a major third played with just intonation creates resultant pitches that are members of a major triad, which can be heard if you listen carefully. These harmonious resultant pitches are a part of what we hear as playing in tune and what we should be striving for when practicing with drones.
Below are two examples of Major 3rds played by sine waves (simple computer-generated tones which contain only the fundamental pitch and no overtones). In the first example, the third scale degree is played a bit too high. Listen for the beats produced by the resultant pitches.
In the second example, the major third is lowered by 14 cents to create an in-tune
For a much more in depth look at science and mathematics of intonation, see A Study of Musical Intonation by Christopher Leuba.
Basic Use of Drone Tracks
The drone track will play the top line of each duet exercise while you play the bottom line. Versions with and without a metronome are provided. When playing without a metronome, you have the extra challenge of relying on your internal rhythm to make sure what you are playing lines with the note changes at each bar line.
Challenge Versions
To further develop your ear and internal rhythm, you can use the challenge versions that accompany each duet. These include versions of the drone track where the drone is left out for a measure or more at a time. The challenge here is to keep making sure your part lines up with the bar lines when the drone comes back in, even though the external timing gets further apart. You also have a chance to make sure your intonation doesn’t stray off course in the measures without a drone.
Other challenge versions include variations of articulation, dynamics, octave, and stopped/open horn.