Джаз : вопросы, инфо, издания, лейблы, музыка

Сколько угодно. Если бы первый пресс бы однозначно определялся одними матрицами, было бы всё просто...


Вообще styrene - это полистирол. В мохнатые годы из такого материалы тоже делали пластинки, больше сорокопятки - они превалировали над гигантами. Вот копипаст из одной статьи.

Styrene (properly, Polystyrene). Hard, relatively inflexible plastic used
to press records, mainly 7-inch singles, mainly using the Injection
Moulding process. The material is heated to a liquid form and is then
squirted or injected into the closed stampers in the press. This requires
that the labels be either glued or painted on after the record leaves the
press. The cost savings to the manufacturer comes from the extended life
of the stampers because of the lack of a heating cycle to the stampers.
The material can also be reused without noticeable change to its moulding
properties. Styrene records will therefore usually have very quiet
surfaces when found in an UNPLAYED Mint condition, but unfortunately they
will wear to a noisy condition rapidly, especially if played with a bad
stylus or an improperly tracking tonearm. They also are more prone to Cue
Burn. The Columbia Records Pittman, New Jersey pressing plant was once the
major source of Injection Moulded Styrene pressings, and pressings from
this plant are found on MANY small labels. Look for the glued-on labels.
Painted-on labels can be found on records from the Amy/Bell/Mala group.

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