Emily Hall and David Sheppard introduce their Electro-Magnetic Harp.
Folie à Deux literally means ‘a madness shared by two’ and in our production a couple who live next to an electricity pylon share the delusion that it has a special power over them. And as their madness takes hold, sparks fly.
I had decided to work with a harp before I even knew what the piece was about, and then when we wanted to set it around an electricity pylon, I wanted to find a way into that world sonically. I started thinking about the combination of a harp and electricity and that led me to the idea of using multiple ‘ebows’ on the harp strings to create drones much like the sound of pylon. The frequency of the electricity hum in the UK is 50Hz and so I needed a harp which was big enough to produce this note (a very low G) and all the other pitches which are part of the harmonic field of the piece. Mahogany Opera Group then commissioned David Sheppard and Jonathan Green (instrument designer) to build the electro-magnetic harp.
The harp itself is a normal lever harp apart from being re-strung with metal guitar strings and the sound generated is purely acoustic. The electronic element is the use of small electromagnetic transducers, one per string that are controlled via a computer and bespoke amplifiers. Each string can be vibrated continuously producing pure sustained notes. To make this a playable instrument we can connect it to a music keyboard or fader controller, which enables the harp to be performed dynamically.’