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WHAT IS "SHIMMER"?
During the recording of The Unforgettable Fire, The Edge & Brian Eno used an unique sound often mistaken as keyboards or strings on such songs as “4th Of July”, With or without you", "All i want is you" (live version) and "Love is blindness" (live version) to name a few. Listen closely for what sounds like an atmospheric string keyboard sound - but is actually Edge playing the guitar heavily treated through an AMS 1580s harmonizer/delay with reverb. Often these sounds are included on multi-effect units and usually referred to as string pads.