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"A voice sitar is a flat board about 4ft long fitted with the same number of strings as the drone strings on a sitar and it includes an electric pick-up and a sending device, enabling you to feed any sound into the instrument, which will vibrate the sympathetic strings. The vibration is picked up and fed back out of the instrument. This is what was done with piano and violin on "Invocation"(U). Our voice sitar is the only one of its kind in the world and was made by an American named Greg Heat. We happened to hear it while in the States and asked if we could buy it."
All that needs to be added is that Robin's voice was, of course, also put through the instrument, giving it that wonderful eerie, oracular quality. After Invocation, the voice sitar was never used again by the band. Theirs was the prototype and Heat reportedly never made another.
text from Melody Maker interview, November 1970, printed in
BeGlad: An Incredible String Band Compendium
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