abstract:MXR, also known as MXR Innovations, was a manufacturer of guitar effects units, co-founded in 1973 by Keith Barr, (who went on to found Alesis) Michael Laiacona (founder of Whirlwind)and Terry Sherwood (who went on to co-found Applied Research & Technology)."In Memoriam: Keith Barr 1949-2010", Mix Magazine Online, Aug 25, 2010 http://www.