Newnes Audio and Hi-Fi Engineer's Pocket Book, 3rd Edition

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Disc materials The main materials used are a vinyl

copolymer, a stabiliser, a lubricant, and a pigment, usually

carbon black. The latter produces the traditional black colour,

but other colours including white have been used. These are

compounded and extruded or fed into the press in the form of

small cakes.

Durability Disc material is subject to two types of

deformation during playing: elastic, from which it returns,

hence is temporary; and plastic, which is permanent, hence is

termed 'wear'.

Direct disc The dynamic range available on disc is limited

mainly by the master-tape recording. To extend it, some

recordings have been made directl ...