Harmonic Seventh Chord - Barbershop Seventh

Barbershop Seventh

barbershop seventh chord. A chord consisting of the root, third, fifth, and flatted seventh degrees of the scale. It is characteristic of barbershop arrangements. When used to lead to a chord whose root is a fifth below the root of the barbershop seventh chord, it is called a dominant seventh chord. Barbershoppers sometimes refer to this as the 'meat 'n' taters chord.' In the nineteenth and early twentieth centuries, these chords were sometimes called 'minors.' " —Averill 2003

The barbershop seventh is the name commonly given by practitioners of barbershop music to the seventh of and the major-minor seventh or dominant seventh chord, when it is used in a barbershop arrangement or performance. "Society arrangers believe that a song should contain anywhere from 35 to 60 percent dominant seventh chords to sound 'barbershop'--and when they do, barbershoppers speak of being in 'seventh heaven.'"

Barbershop music features both major-minor seventh chords with dominant function (resolving down a perfect fifth), often in chains (secondary dominants), and nondominant major-minor seventh chords.

Beginning in the 1940s, barbershop revival singers "have self-consciously tuned their dominant seventh and tonic chord in just intonation to maximize the overlap of common tones, resulting in a ringing sound rich in harmonics" called 'extended sound', 'expanded sound', 'fortified sound', "the voice of the angels". The first positive mention of such practice appears to be Reagan, 'Molly' (1944). "Mechanics of Barbershop Harmony", Harmonizer. The example of a dominant chord tuned to 100, 125, 150, and 175 Hz, or the 4th, 5th, 6th, and 7th harmonics of a 25 Hz fundamental is given, making the seventh of the chord a "harmonic seventh".

There's a chord in a barbershop that makes the nerve ends tingle....We might all our chord a Super-Seventh!...The notes of our chord have the exact frequency ratios 4-5-6-7. With these ratios, overtones reinforce overtones. There's a minimum of dissonance and a distinctive ringing sound. How can you detect this chord? It's easy. You can't mistake it, for the signs are clear; the overtones will ring in your ears; you'll experience a spinal shiver; bumps will stand out on your arms; you'll rise a trifle in your seat." —Art Merill

It is normally voiced with the lowest note (the bass) on a root or a fifth, and its close harmony sound is one of the hallmarks of barbershop music.

When tuned in just intonation (as in barbershop singing), this chord is called a harmonic seventh chord.