Loved by guitarists for decades, it's a Japanese-made modulation-type effect unit that made a blazing debut at the Woodstock festival; you already know the one we're talking about. The inimitable sound of this distinctive modulation effect has captivated numerous guitarists and audiences. Yet, because only a very small number of the original units exist and because the circuit itself was not accurately understood and its components were difficult to obtain, it was rare to have the opportunity to try out the unit that produced these famous sounds. Such factors elevated the original to a semi-divine status. Numerous clone models were produced by major manufacturers and boutique shops alike. However, all of these remain facsimiles that are pale imitations of the original model.