Sony Corp., the company that brought us the Walkman and the parent company of music label Sony Music Entertainment, plans to shut down a CD-manufacturing plant in southern New Jersey in March.

About 300 employees will be laid off once the 50-year-old Sony DADC plant in Pitman, N.J., is closed. Sony said it plans to shift CD-making operations to a facility in Indiana. The company moved DVD manufacturing from the plant about a year ago.

Lisa Gephardt, a Sony spokeswoman said in a statement: "In light of the current economic environment and challenges facing the physical media industry, Sony DADC is taking additional steps to reduce cost from our supply chain network in order to remain competitive."

Who couldn't see these kinds of closures coming The music CD has become nearly a relic. The emergence of digital music and music players, as well as the rise of illegal file sharing, helped to hasten the demise of the CD as the main music distribution format.

According to Nielsen SoundScan, U.S. music sales fell 2.4 percent last year and digital track sales grew only 1 percent to 1.17 billion. But CD sales fared far worse. When it came to albums, sales of both newer CDs and catalog titles dropped by 16 percent and 23 percent respectively--these two categories also saw double-digit losses the previous year, according to the Los Angeles Times.

The CD was a boon for the record industry. Not only did record labels cash in when music buyers replaced their cassette tapes and vinyl records with discs, but the CD also helped prevent unauthorized copying--at least initially. CDs also discouraged people from buying singles, prompting them to purchase full albums instead.

The plant closure is just another sign that physical media's days are numbered. In addition to music, the film and book industries are amid their own digital transformations. Netflix and Apple are helping to fuel the emergence of Web TV. The Kindle and iPad are helping to drive consumer interest in e-books. How far this goes is anybody's guess but one has to wonder how long printed books and DVDs will be with us.