Electronic Frequency of Musical Notes

by Steven J. Miller

Learning about the electronic frequencies of musical notes makes it possible to use filters in digital audio programs to isolate specific instruments. For instance, if you want to remove the violin part from a string quartet, it is possible by using a filter that removes any notes played in the violin part. In the case of a violin, you would set your audio program to remove any frequencies below the G string, in this case 196 hertz. Of course, there is more to the story than simply removing frequencies, but with additional editing, it is possible to isolate individual instruments. The first step, however, is to determine the frequencies of the notes you wish to remove.

Hearing Range

The audible human range of hearing falls between E, approximately three octaves below middle C, to D, approximately six octaves above middle C. The average human can hear anything between 20 hertz to 20,000 hertz. Hertz consists of the number of cycles a waveform completes in a single second. The faster the vibrations, the higher the sound. As people age, their hearing naturally declines and they lose the bottom and top of their natural range of hearing. To minimize hearing loss, avoid loud sounds for extended periods of time.

Middle C

Middle C serves as the transition point between the bass and treble clef. Middle C has a frequency response of 262 hertz. The lowest C begins below the threshold of normal human hearing at 16 hertz. Notes in the lowest frequency range start sounding less like notes and more like rumblings.

Concert A

Performers use concert A or A 440 to tune their instruments to ensure that all of the instruments in the ensemble play the same pitch. A 440 occurs six notes higher than middle C. Every other pitch on the instrument tunes relatively to this pitch. The piano is the only instrument that tunes slightly higher than A 440. As a general rule, it is better to be sharp than flat, since flat pitch is more detectable. Because the piano requires hours to tune properly, tuners will bring the pitch slightly higher to compensate for the tension placed upon the strings. This helps to keep the piano from falling out of tune.

Frequency Doubling

All pitches approximately double at the octave. To reach a higher frequency, the vibrations must increase in speed by two. This explains why the lowest C in the spectrum consists of just 16 hertz, while the next C consists of 33. Using this formula, it is possible to figure out all of the other notes in the spectrum. C sharp, D and D sharp begin on 16, 17 and 18 hertz respectively. E, F and F sharp begin on 21, 22 and 23 hertz. G and G sharp consist of 25 and 26 hertz. A and A sharp hold 28 and 29 hertz, while B starts on 31 hertz.


About the Author

Steven Miller graduated with a master's degree in 2010. He writes for several companies including Lowe's and IBM. He also works with local schools to create community gardens and learn environmentally responsible gardening. An avid gardener for 15 years, his experience includes organic gardening, ornamental plants and do-it-yourself home projects.