QED Performance XT25 Speaker Cable (Pair) (2 metres)

Product Information

It is not generally appreciated that the electrical signals moving at or near the speed of light in a wire do so via the medium of electromagnetic (EM) waveforms which exist within the dielectric which surrounds the conductors as well as within the conductors themselves. The movement of electrons along the conductor merely facilitates generation of the EM waveform as their “drift velocity” is only a few centimeters per second. It is therefore important to ensure that the dielectric material used to insulate and protect the central conductors of the speaker cable is of a type which “permits” the establishment of EM waveforms without appreciable loss. Dielectric losses are directly proportional to the “permittivity” of the material used and as this a measure of each material relative to that in a vacuum it should be as close to unity as possible. Like its predecessors, XT25 uses a specially formulated low-density polyethylene (LDPE) dielectric which at 1.69 has the lowest relative permittivity practically available.

QED’s extensive research has uncovered the importance of cable dielectric (insulation) in optimising the sonic performance of a cable. The XT40i has improved on an already successful cable by designing a groundbreaking Air Gap™ dielectric construction. This technology reduces the cable’s dissipation factor and capacitance by half, resulting in vastly improved musical timing, a wider soundstage and improved bass control over its predecessor. As frequency increases, electrons flow more and more towards the periphery of a conductor so that if the frequency is high enough only a very thin layer (or skin) on the outside of the conductor is used. This “skin depth” varies for different materials at a fixed frequency and in copper it means that if a conductor has larger than 0.66 mm 2cross-sectional area not all of that area is available for an analogue music signal to use.The graph below shows how the dc resistance of XT25 remains effectively unchanged across the entire audible frequency band when compared to a conventional cable of the same cross-sectional area. Combined with the sonic advantages of a low loss dielectric the improvements in current distribution place the new cable in a class well above cables with a less sophisticated geometry. Then there’s the baffle. As far as I know, an inset baffle offers no benefit at all. It may look cool -- the Linton Heritage’s baffle is attractively framed by the cabinet’s edges -- but those edges create a nightmare of diffraction. Diffraction happens when a driver’s soundwaves, as they traverse the baffle, meet an obstruction such as a raised edge -- they bounce off these obstructions, to then interfere with the initial, undiffracted soundwaves now directly emerging from the driver. Depending on how the diffracted soundwaves interact with the direct wavelaunch, it can often cause a visible spike or dip in the frequency response.

It is not generally appreciated that the electrical signals moving at or near the speed of light in a wire do so via the medium of electromagnetic (EM) waveforms which exist within the dielectric which surrounds the conductors as well as within the conductors themselves. The movement of electrons along the conductor merely facilitates generation of the EM waveform as their “drift velocity” is only a few centimetres per second. It is therefore important to ensure that the dielectric material used to insulate and protect the central conductors of the speaker cable is of a type which “permits” the establishment of EM waveforms without appreciable loss. Dielectric losses are directly proportional to the “permittivity” of the material used and as this a measure of each material relative to that in a vacuum it should be as close to unity as possible. Like its predecessors, XT25 uses a specially formulated low-density polyethylene (LDPE) dielectric which at 1.69 has the lowest relative permittivity practically available. Before I describe the sound of the Linton Heritage, I want to talk about some of the acoustical challenges of speakers, like this one, shaped like models from the 1960s and ’70s, and why you don’t see many of them nowadays. First is their wide front baffles. Most speakers today have fairly narrow baffles, to reduce the amount of surface area that can reflect soundwaves produced by the drivers -- a kind of interference called diffraction. This is one of the things that helps modern speakers get out of their own way, to produce a more open and boxless sound. Hifiman2007 said:As I said I do think analogue cables can sound different. However sometimes different is not better. Monster cables for instance have gone virtually bust because it was made clear that they sold overpriced cables that made no difference ....hifi magazines claimed they did and regularly reviewed as such. Obviously sold advertising space. So I think what hifi and other reviewers have a duty to make it clear they prefer the sound of the cable and not blindly say "it is better" I just wish they would take blind tests without knowing price ,brand, of item that would be more realistic and accurate. Anyone would be influenced by knowing price or brand first. Having spent the last 30 years in Hi-Fi, AV and Custom Install I'd have to say that never once have I been able to work out the supposed correlation between AV Kit costs and the cost of the speaker cable's I use to connect the Amp to the Spks.Audiophiles aside, most people are not keen on spending a chunk of money on cables and they are justified. Unless you are a music aficionado, you will not notice the subtle change in audio quality as a result of the wires. However, the QED Reference XT40i is an exception, and the audio quality produced as a result of it is unmistakable. QED’s innovative proprietary X-Tube™ technology means the XT40i exhibits less distortion at high frequencies than standard speaker cables, improving overall performance through a level of timing and imaging usually found on much more expensive cables.

Bare wire connections are fine for speakers and help you get them closer to the wall - although this is usually not a good thing from a sonic perspective, as it will usually reduce the bass response and can make things sound a bit lumpy. Most speakers unless designed to be used up against a wall want a minimum of 6" clear space and preferably 12". QED's reputation for innovation and technical excellence is known throughout the world. The latest computer-aided design techniques allow their research and development team to keep pace with technological advances and deliver products that achieve the highest levels of performance and reliability. This is why QED products are recommended by so many of the world’s leading hi-fi and home theatre equipment manufacturers. Triple magnet screening and 24K gold plugs makes our Performance USB A-Mini B the best in its class. This cable is custom-made according to customers specific requirements as selected by the various dropdown options above and is professionally terminated by Futureshop's expert engineers using QED's superb 24 Carat gold plated AIRLOC termination plugs. At 2 metres each, these terminated cables are ideal for desktop and smaller rooms and when your hi-fi is between the speakers. With the plugs already fitted, simply plug in and go.

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Using our in house HDMI testing facility, QED have designed premium HDMI cables to suit any budget. From our flexible and slimline profile to our exceptional Reference HDMI with its BandPass filter technology to reduce Jitter to Ultra low levels OPTICAL The cable uses a variation of QED’s X-Tube™ Technology by creating a hollow tubular conductor geometry out of individual conductor bunches. This allows both high and low frequencies to pass with equal ease when compared to traditional solid or stranded conductors.