Directionality Assurance
All Supra cables are constructed with attention to consistent and equal ‘direction’ in all the conductors. Simplistic electronics theory says there is no ‘directionality’ in conductors, but assumes conductors are perfectly isomorphic. It also ignores the inherently directional nature of signal and energy flow. Yet electricity could not be sold without ‘energy flow directionality’. [1] In reality, practical conductors are drawn many times - not cast. This creates highly elongated crystal structures. This in turn creates a physical (mechanical) directional feature or ‘axial polarity’. Annealing and also ‘burning-in’ processes can reduce the ‘strength’ of the ‘drawing imprint’, but only to a degree. All conductors in Supra cables are consistently arranged to point ‘forwards, in the direction (left to right) implied by the legend (text) printed on the cable jacket. Directional consistency is ensured in two ways. First, direction of the conductors to be used in each cable is known from the spooled direction of the conductors received from the copper wire factory. That is a reliable method because an efficient manufacturing process is consistent and omits random re-spooling steps.

Forward Thinking Technology
Second, the ‘directionality’ of conductors is now able to be measured, and Supra cables are the first in the world to benefit from a spectral technique developed by audio consultant Ben Duncan [2] in conjunction with Jenving Technology AB. This employs some special test conditions which better approximate audio equipment’s real-world usage than standard, pure signal sources. Test results show typical increases in harmonic (noise) levels 0.5dB when cables are connected so the conductors’ drawn direction opposes the signal flow direction. In real use the noise difference, which is some dB below the main signal, could be much greater. From this, a reduction in such noise (‘more clarity’) is what’s expected, and it is also one of the things that is heard in practice - when optimum conductor orientation is discovered.

Experiences of Directionality
In ‘high-end’ audio, ‘Directionality’ means: ‘a cable used for audio signal transmission offering better sound quality (in various ways) when connected a particular way round.’ To those sensitive to the sonic changes, this is repeatable, over spans of time, or in different systems. In other cases, if the less good direction were chosen, it too may approach the preferred direction after burn-in, i.e. a period of use, simple ageing, or even cryogenic treatment. Such ‘burn-in’ processes involve annealing of the metal.

Some pundits say that ‘directionality’ (in cables) can be heard even on the low quality ‘curvy plastic’ low/mid-fi audio equipment sold in high-street shops. On an higher vector, a US high-end enthusiast/ researcher, Doug Blackburn, suggests it is possible that when audiophiles say they hear sonic changes after changing polarity (by swapping conductors at one point - not by swapping ends as with conventional directionality*) that they’ve actually heard directionality instead. That’s because purely digital (‘software’) polarity reversals mysteriously don’t have the sonic attributes associated with analogue signal polarity reversal.

*Here, directionality effect being heard is in the connected parts (eg. long inductor wires), rather than in the preceding connective conductors.

Information
[1] For background, refer to extensive insights in ‘Black Box’ column, by Ben Duncan, originally in Hi-Fi News& Record Review, reprinted 73 part compendium 1994-2000 available from:
www.hifiaccessoriesclub.com or www.proaudioaccessories.com

[2] Ben Duncan Research:
www.benduncanresearch.com