Wireworld founder David Salz has long maintained that the only true test of a cable’s quality is to compare it not against another cable, but to no cable at all. In his more than 30 years of designing cables, he’s been using the same technique of comparing cables under development to a direct connection: It takes a bit of component juggling, but it’s possible to position two components with their rear panels facing each other and connect them with a 2-inch-long “S”-shaped connector with RCA plugs on both ends. The system’s sound is then compared with the direct connection against the cable under evaluation.
Salz sent me some of these double RCA plugs probably about 20 years ago, and I’ve tried the technique a few times. You must have components whose arrays of input and output jacks lend themselves to direct connection. It’s quite tricky to arrange physically, but when done right, it provides an illuminating insight into exactly how each cable affects the sound.
Salz turned this internal design technique into a fascinating public seminar at this year’s Rocky Mountain Audio Fest. In the hotel’s small amphitheater, he had set up a modest system with a Rube Goldberg-like stand that held the sources and mono amplifiers in position so that the system could be connected without speaker cables. Salz explained the bypass test—which he renamed the “Cable Polygraph” for the public event—to the packed room. He then proceeded to play paired comparisons of a direct connection vs. a particular cable, some of them from competitors. Even with the modest system and less than ideal listening conditions, the colorations imposed by each cable were immediately obvious. Although no cable is perfectly transparent, Wireworld’s cables, particularly their upper-end models, sounded quite close to the direct connection. Moreover, some of the non-Wireworld cables were revealed to be grossly colored. Overall, the bypass test proved its usefulness in evaluating cables. It also clearly showed the wide range of sound qualities of cables on the market. If Salz repeats this “Cable Polygraph” demo at future shows, I encourage you to attend. — Robert Harley