VIOLIN

Harmonics in a violin tone

This demonstration analyzes the harmonics of a tone produced by a violin.

A recording of a single violin tone is analyzed. The pitch is about 497 Hz which is the B above concert A. The recording is contained in the file, VIOLIN.WAV. The wave form of this violin tone is shown in the file, VWAVE.JPG.

A frequency spectrum of this violin tone was produced from a fourier transform of the wave form. The first peak is at 497 Hz, the fundamental frequency (the first harmonic). The second peak is at 994 Hz, the second harmonic, etc. Each peak represents one of the harmonics of the tone. The spectrum is shown in the file, VSPECT.JPG.

The violin tone was decomposed into separate harmonics. The program, VIOLIN.EXE, is an animation of the sound wave which we hear, showing how each harmonic is added, one at a time, to produce the final wave form of the violin note. See notes below about operation of this program.

A sound file was generated from these eight harmonics. Each harmonic is added, one at a time, to the tone. After a brief pause at the end, the original violin tone is also played for comparison. The sound file is contained in the file, VHARM.WAV.

The program, VSTRING.EXE, is an animation of the actual standing waves on the violin string, showing the motion of the string as each harmonic is added. See notes below about the operation of this program.

A tone produced by a trumpet was recorded for comparison. The recording is contained in the file, TRUMPET.WAV. Compare this tone with the violin tone contained in the file, VIOLIN.WAV. The overtones were stripped from both of these tones, leaving only the first harmonic. The result is contained in the files, VIOLIN1.WAV and TRUMPET1.WAV. These two tones sound identical. The higher harmonics give instruments their characteristic sounds.

VIOLIN, OpenGL Version

This version of the program plays sound files. You hear each harmonic as it is added.

The program recognizes the following commands. The command may be executed by either clicking the button with the mouse (first column below) or by pressing a key (second column below). The mouse buttons may be removed from the screen by pressing the M key. Press M again to restore buttons.

next(any key) Next harmonic.
add(any key) Add harmonic to wave.
quitQ Quit program.

VSTRING, OpenGL Version

This version of the program plays sound files. You hear each harmonic as it is added.

The program recognizes the following commands. The command may be executed by either clicking the button with the mouse (first column below) or by pressing a key (second column below). The mouse buttons may be removed from the screen by pressing the M key. Press M again to restore buttons.

pauseS Stop animation. Press G to resume animation.
resumeG Resume animation.
next(any key) Next harmonic.
add(any key) Add harmonic to wave.
quitQ Quit program.

VIOLIN and VSTRING, DOS Version

Press any key to step through the program.
Press ? at any time to see a help screen.
Press Q at any time to quit the program.