Supra Sword Excalibur Loudspeaker Cable

hfnedchoiceSweden's Supra brand was in the vanguard of the cable revolution in the late '70s so its new and vibrant Excalibur flagship is no mere stab in the dark.

With its blue-tinged foil screen positively glowing through a tight, translucent PVC jacket, Supra's flagship speaker cable, priced at £1700 for a 3m terminated set (£300 per additional stereo metre), makes for a vivid statement. It's a world away from the speaker cables that helped Tommy Jenving launch his Swedish Supra brand in 1976. Its Supra Cable 4 and 2.5 used bunches of very fine copper strands in a standard figure-of-eight geometry. Its later 10mm2 Supra Cable 10, with 2562x0.07mm 4N copper strands, still has the lowest series resistance that I've measured (3.1mohm/m) when tested nearly 30 years ago [Hi-Fi Choice Aug '94].

Fast forward to today and the range-topping Excalibur version of its Sword cable now features a foil screen over its symmetrical, bifilar-wound signal and return cores. Here two sets of 12 enamel-coated 5N OF-copper strands are wound at 90° to each other over a hard PE core and separated with a layer of softer PE insulation. The coarse Litz-like geometry is intended to trade higher capacitance for lower inductance while the enamel-coating eliminates inter-strand conduction. Finally, Supra's crimped 'CombiCon' cable terminations may be fitted with rhodium-plated 4mm bananas or spades.

Now, whether you choose to ground the Excalibur's foil screen to your amp via one or more of Supra's separate XL-Annorum conductors [see pic, above] does not affect the cable's lumped parameters, including the 0.47µH/m series loop inductance. This is an 'average' rather than particularly low figure – Supra claims 0.25µH/m which is very close to the 0.23µH/m we measured for In-akustik's LS-204 XL cable [HFN Feb '21], another helically-wound derivative claiming low inductance. The specified 5.2mohm/m resistance precisely matches the AWG linear-metre standard for a solid 12-gauge (3mm2) copper conductor, but our figure for a terminated length was a higher 17.9mohm/m loop, equivalent to a 0.019dB/m power loss into an 8ohm load. Parallel capacitance is also a perfectly moderate 151pF/m.

sqnote Cutting Edge
In addition to my usual Constellation Centaur II 500 [HFN Dec '19] and B&W 801 D4s [HFN Nov '21], I was blessed with more than a few other amp/speaker combinations this month with which to sample the potentially Arthurian qualities of this particular Excalibur. With most of these systems – and especially the Western Electric 91E [HFN Feb '23] with DeVore O/93s – the Sword Excalibur encouraged what I'd best describe as an arresting, animated sound.


Inside the Excalibur showing the multistrand bifilar-winding of each conductor around a polyethylene core. The foil screen, drain wire and fibre packing are also clearly revealed

Bass, notably, had a richer 'colour' than I'd heard with other high-end cables, bringing extra weight, impact and sheer 'bounce' to Grischka Zepf's strumming on Chris Jones' 'No Sanctuary Here' [Roadhouses And Automobiles; SFR 357.8006.1] just as it helped lift Paul Chambers' bowed solo on 'Red Pepper Blues' [Art Pepper Meets The Rhythm Section; Contemporary/Original Jazz Classics S7532]. Treble, too, was sweet with just the right bite given to percussion and plucked strings, even if the extreme top-end was arguably slightly 'dark' rather than brightly lit. Many listeners will prefer it this way, of course, but that's the beauty of a cable that beguiles as it informs.

Hi-Fi News Verdict
If you can tear your eyes away from this bright blue cable and focus on the sound then you're in for a treat. Why? Because Supra's Excalibur achieves a momentum of its own as it rolls with rock as enthusiastically as it fans the thunder of an orchestral climax. Even if it's not entirely transparent-sounding, any colour it brings is both subtle and sympathetic, and delivered at a price – £1400/2m set – that's pitched well below that of audio's apex cables.

Price £1700 (3.0m terminated stereo set)