These passive systems are intended to reduce a broad range of high-frequency noise picked up by and created by electronics, as well as RF noise that gets into connecting cables and components from the AC mains. MF tried the two-socket GC1 and the six-socket GC3 along with CAD cables ($350 each) that connect on one end to the Ground Control units with 4mm banana plugs and are terminated on the other end with USB, RCA, XLR, spade, and 4mm banana plugs. He found with one of his favorite LPs that the Ground Control system resulted in “more delicate” sound but with still well-articulated attack. The background was blacker, recorded strings had more luster, female voices were smoother, and sibilants were more cleanly expressed so that the LP sounded “more ‘there’ and less recorded.” He subsequently wrote that “Now that I’ve lived with it for another couple of months, I can render my verdict: I can’t live without it.” (Vol.43 Nos.7& 9 WWW)