wct@mordor.UUCP (Bill Thompson) (10/30/84)
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Submitted without comment:
From "New Scientist", 11 October, 1984, pp 22.
"Hi-fi benefits from crystal-clear sound"
A development from Hitachi in Japan could make all existing quality sound recording
and reproduction systems obsolete. The company is selling copper wire made up of
long crystals which are free from oxygen.
For years, hi-fi enthusiasts have claimed that the cabling in recording and
reproduction systems can colour sound. Thick, multi-strand cable costing several
pounds a metre makes a subtle difference, but the reasons why are not fully
understood. When a microphone is connected to a recording console in a studio by
copper wire, there is inevitably some loss of signal because the wire has
electrical resistance. The effect is well known from Ohm's law. But if the
copper contains oxygen impurity, barriers of copper oxide form between adjacent
crystals in the copper. Although the effect is not well understood, it is known
that these oxide layers act as partial rectifiers, which alter the characteristic
of the audio signal and change its sound. So cable made from oxygen free copper
results in a better sound than that carried by ordinary copper.
Hitachi has now pinpointed an effect which is even less understood. If oxygen
free ingots of copper are heated slowly, they form crystals which are 10 times
the size of those in normal copper. When this long crystal copper is drawn through
a die to make cable, the crystals stretch rather than break. The result is oxygen
free copper cable with one thousandth the nuber of barriers between crystals along
its length, and so fewer copper oxide barriers.
When this cable is wired into an audio system it is, as one audio critic put it, like
lifting a veil from the sound.
--
William C. Thompson III (S-1 Project, Lawrence Livermore National Laboratory)
U.S. Mail: LLNL, S-1 Project, P.O. Box 5503, L-276, Livermore, Ca., 94550
Phone: (415) 422-0758
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