I’ve been playing guitar for just shy of three decades, and while I still find newer guitarists who inspire me, it was my early heroes who inform much of my musical sensibilities. One of these is Jimi Hendrix, who I would argue is one of the grandfathers of Heavy Metal. Another is Tony Iommi from Black Sabbath; if Hendrix is Metal’s granddaddy, Iommi is its doting father. Both of these composer/guitarists re-introduced an old chord into their new sound: the tritone, also known as the Diabolus in Musica, or more commonly, the Devil’s Chord. To hear this interval in action, pop on the intro to Hendrix’s Purple Haze, or take a spin with Black Sabbath’s first album. Or just listen about anything Heavy Metal.

For my fellow musicians, this relationship can be described as any chord or progression that involves diminished fifths. Everyone else can ignore that bit. But where does it come from? And just how diabolical is it?

Following are the words of Giuseppe Tartini, an Italian  violinist whose most famous work is called The Devil’s Trill Sonata. Written somewhere between 1713 and the mid 1740s (music historians debate the actual date of composition) it is a piece that still tests the limits of even accomplished violinists. This is what he had to say about his masterwork:

One night, in the year 1713 I dreamed I had made a pact with the devil for my soul. Everything went as I wished: my new servant anticipated my every desire. Among other things, I gave him my violin to see if he could play. How great was my astonishment on hearing a sonata so wonderful and so beautiful, played with such great art and intelligence, as I had never even conceived in my boldest flights of fantasy. I felt enraptured, transported, enchanted: my breath failed me, and I awoke. I immediately grasped my violin in order to retain, in part at least, the impression of my dream. In vain! The music which I at this time composed is indeed the best that I ever wrote, and I still call it the “Devil’s Trill”, but the difference between it and that which so moved me is so great that I would have destroyed my instrument and have said farewell to music forever if it had been possible for me to live without the enjoyment it affords me.

A Faustian pact indeed!

An interesting asides: Indian classical music is filled with this interval; in fact, it figures in one of Hindustani music’s core ragas, or musical scales. I suppose the Devil might have gone down to Georgia, but His Infernal Majesty never quite made it past the Ganges.

P.S. if, at your eternal souls own risk, you do play this chord, and the Devil does show up, tell him I have the twenty dollar bill he loaned me (all apologies to Friend of the Devil by the Grateful Dead).