Yleistä keskustelua musiikista ›

"What is a matrix number?
 
When a vinyl disc was made, the first stage (after recording the music of course) was to cut an master disc, usually on an oversized disc made of aluminium coated in acetate or lacquer. A heated stylus (sometimes cooled by helium) would literally cut the groove of the disc into the lacquer and this master would be coated, electroplated (usually more than once) and finally stamped in a steam-heated press to produce the vinyl disc. In order to identify the acetate disc used to make a particular disc the cutting engineer would inscribe or stamp a reference number into the surface of the cut disc, between the end of the music and the space for the label. This is where the run-out-groove or scroll would be. Often this so-called Matrix Number would just be the disc catalogue number with A or B or 1 or 2 after it to show which side. Sometimes obliterated matrix numbers on discs can show changed release schedules.
 
Some companies (such as EMI on discs such as the 1960s Beatles albums) decoupled matrix numbers from catalogue numbers although there would almost always be a listing of the matrix number on the disc label. Even in these cases the matrix for the 'A' side would be lower than that for the 'B' side. In this way you can often identify discs where the A and B sides have been 'flipped'. Other information would sometimes be added to denote the pressing plant (many Elektra discs have this since individual LPs were pressed in more than one plant across the US) or give a sequence number to the cut or stamper. In the 1970s it became the fashion for disc cutting engineers to 'sign' their matrixes. (An example being Porky's Prime Cut') Sometimes cryptic remarks would be inscribed, and on one notorious occasion an Elvis Costello album had a message in the run-out asking people to phone the record company press officer and claim a prize!"
 
http://www.collectorshelp.com/popups/matrix.htm
 
http://www.cris.com/~oakapple/gasdisc/matrix3.htm
 
http://www.iasa-web.org/icat/icat005.htm
 
http://www.superseventies.com/faq_vinyl.cd.html