QED Reference X-Tube XT40i

XT40i
XT40i with X-Tube™ Technology
As befits a company rapidly closing in on its fifth decades at the forefront of speaker cable design, QED’s brand new XT40i speaker cable builds on the formidable reputation of the XT40 cable it replaces and offers a decisive step up in sound quality.
This pure oxygen-free copper cable uses an evolution of QED’s established X-Tube technology to guarantee superb timing and stereo imaging, and adds the brand new and highly innovative Air Gap dielectric to bring unheard-of rhythmic accuracy and musicality to a cable of this modest price. Very low DC resistance adds unrivalled frequency response to XT40i’s already potent audio capability. The result is a cable that advances on the class-leading standards set by its predecessor.
We urge you to audition XT40i - we’re confident you’ll agree it even outperforms alternative cables at many times the price. Prepare to be surprised and delighted.
AWARDS AND REVIEWS

Air Gap dielectric
By increasing the separation of the conductors inside the cable, and therefore the amount of air between them, QED has created a low-loss Air Gap dielectric. This technology halves the dissipation and capacitance characteristics of the cable, and results in numerous audible improvements - particularly where timing and rhythmic accuracy are concerned. Despite this increased separation, though, XT40i retains the sort of cross-sectional area that makes it ideal for long cable runs.
X-Tube technology
Forming the cable conductors into a tube-like shape around a hollow insulating rod in the centre of the cable equalises current densities, delivers very low inductance and presents a consistent, even load to an amplifier. The result is a cable that retains more of the finest musical details, that handles rhythms and tempos in the most natural and musically satisfying way, and that outperforms rival designs costing far more.

Specification:
Outside diameter: 6 x 14 mm
Conductor area: 4 mm²
Dielectric properties: Air Gap (εr = 2.4)
Conductor chemistry: 99.999% oxygen-free copper
Dielectric properties: Air Gap
Loop resistance: 8.0 mΩ/m
Parallel capacitance: 35 pF/m
Dissipation factor @ 10kHz: 0.0295
Self-inductance: 0.57 μH/m