MIT cables are distinguished by having boxes fitted in the line of the cable. The least expensive cables, whether interconnects or loudspeaker cables, come equipped with boxes the size of a small bar of chocolate; the more you pay, the bigger the boxes. The Magnum MA loudspeaker cables boast boxes the size (and weight) of a house brick, the Oracle MA-X’ boxes are bigger than many monoblock amplifiers. (At least, with MIT, you can see some of what you have paid for). How the boxes work is something of a trade secret, but various white papers on the MIT website do help to explain the rationale behind their use.
In effect, MIT argues that signal propagation down a cable varies with frequency. The ‘skin effect’ of radio-frequency transmissions (which propagate almost entirely down the surface of a conductor) is fairly well-known, but MIT explain that even at audio frequencies, the signal uses different thicknesses of the cable at different frequencies. So low bass (which is close to DC, travels down the cable using most of its cross-section, whereas upper treble (which is closer to low-frequency radio transmissions than to DC) penetrates only part way down from the skin of the conductor.
This affects not only the measured resistance of the cable, but also those reactive properties such as inductance and capacitance, and these properties therefore are understood to be frequency-dependent to an extent which is audible. These reactive properties mean that the phase relationship between low and high frequencies is distorted, leading to smear, time domain distortions and, to use MIT’s preferred term, a loss of articulation.
The boxes contain passive networks which compensate for this by ‘re-timing’ the signal so that the low frequencies arrive at their destination properly synchronised with the high frequencies. These networks can be thought of as similar to filter networks, except that, being passive, the signal does not pass through them. Each network, or ‘pole’ of articulation, deals with a particular frequency band. The better the cable, the more poles of articulation and the bigger the box. More poles means each pole can deal with a narrower frequency range and can be more precisely tailored.
In the ‘MA’ series, MIT have developed networks which also preserve the harmonic structure within tones, so that the normal consonant and dissonant harmonics in a note retain their proper relationships to each other, the amplitudes of any given harmonic more closely resemble those of the original tone. What this means in effect, is that the tonal differences between, say, an oboe and a cello playing the same note, are down to the interrelationships between the various harmonics which make up the note. MIT argue that most cables affect the amplitude, and subtly adjust the frequencies of these harmonics, to the detriment of the sound. The MA technology is designed to minimise that distortion.
Because the boxes are such a large part of the budget in any MIT product, the price depends rather less on the length of the cable than it does in more conventional interconnects and loudspeaker cables.
The MIT Oracle MA-X loudspeaker cables
Price: 2.5m pair £26,000
3m pair £26,500
3.6m pair £27,000
4.5m pair £27,750
For bi-wire versions add £1,800 inc VAT to the above prices.
Manufactured by Musical Interface Technologies
Distributed by Audiobility
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