“Maria” from Westside Story by Bernstein, the “Prelude to Tristan and Isolde” by Wagner and Jimi Hendrix’s “Purple Haze” all feature a musical interval that can stir emotions and the catholic church tried to ban. An interval is a distance between any two notes. These two musical notes have become known as the “Devils Interval”. This interval splits the 7 different notes of the 8 note major scale exactly in half. For example, C to F# and F# to C is called officially a tritone. Bernstein and Wagner resolve the interval which has a tension release, Hendrix does not.
One or two musical notes can have a strong emotional effect especially when associated with text or visual images. Opera, TV and movie composers know this well. The Catholic Church also understand this.
“They [the Catholic bishops] shall also banish from churches all those kinds of music, in which, whether by the organ, or in the singing, there are mixed up anything lascivious or impure; as also all secular actions; vain and therefore profane conversations, all walking about, noise, and clamor, that so the house of God may be seen to be, and maybe called, truly a house of prayer.” Session of the Council of Trent that took place on September 17, 1562.
The siren sound in Europe and the USA often use the devil’s interval or tritone.
The Catholic church’s ban on opera didn’t last nearly as long as a prohibition on the tritone, the so-called devil’s interval. The augmented fourth (or diminished fifth) was considered as Satan’s work and outlawed through the Middle Ages. This dissonant interval wasn’t employed as much until Romantics, such as Richard Wagner, used the eerie chord to spooky effects.
This interval is very much part of the blues scale. For example, in the C blues, you have C, E flat, F, (F#), G and B flat. The interval is part of the dominant chord and the diminished chord.
Bach had to “Handel” this chord carefully and he did it most skillfully. For more on Leonard Bernstein “Westside Story” and the devils’ interval see this article on the ClassicFM website.
Jonathan Lane, artistic director