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===Digital audio recordings===
{{Main|Digital audio|Digital recording}}

In 1967, the first PCM recorder was developed by [[NHK]]'s research facilities in Japan.<ref name="Fine">{{cite journal |author=Thomas Fine |year=2008 |title=The dawn of commercial digital recording |journal=[[Association for Recorded Sound Collections|ARSC Journal]] |volume=39 |issue=1 |pages=1–17 |url=http://www.aes.org/aeshc/pdf/fine_dawn-of-digital.pdf}}</ref> The 30&nbsp;kHz 12-bit device used a [[compander]] (similar to [[Dbx (noise reduction)|DBX Noise Reduction]]) to extend the dynamic range, and stored the signals on a [[video tape recorder]]. In 1969, NHK expanded the system's capabilities to 2-channel [[stereo]] and 32&nbsp;kHz 13-bit resolution. In January 1971, using NHK's PCM recording system, engineers at [[Denon]] recorded the first commercial digital recordings.<ref group=note>Among the first recordings was ''Uzu: The World Of Stomu Yamash'ta 2'' by [[Stomu Yamashta]].</ref><ref name="Fine"/>

In 1972, Denon unveiled the first 8-channel digital recorder, the DN-023R, which used a 4-head open reel broadcast video tape recorder to record in 47.25&nbsp;kHz, 13-bit PCM audio.<ref group=note>The first recording with this new system was recorded in [[Tokyo]] during April 24–26, 1972.</ref> In 1977, Denon developed the portable PCM recording system, the DN-034R. Like the DN-023R, it recorded 8 channels at 47.25&nbsp;kHz, but it used 14-bits "with [[Emphasis (telecommunications)|emphasis]], making it equivalent to 15.5 bits."<ref name="Fine"/>

In 1979, the first digital pop album, [[Bop till You Drop]], was recorded. It was recorded in 50&nbsp;kHz, 16-bit linear PCM using a 3M digital tape recorder.<ref>{{cite web |author=Roger Nichols |url=http://rogernichols.com/EQ/EQ_2001_08.html |archive-url=https://web.archive.org/web/20021020102042/http://rogernichols.com/EQ/EQ_2001_08.html |archive-date=2002-10-20 |title=I Can't Keep Up With All The Formats II |quote=The Ry Cooder Bop Till You Drop album was the first digitally recorded pop album}}</ref>

The [[compact disc]] (CD) brought PCM to consumer audio applications with its introduction in 1982. The CD uses a [[44,100 Hz]] sampling frequency and 16-bit resolution and stores up to 80 minutes of stereo audio per disc.