Compact Disc
The Red Book CD specification includes two channels by default, and so a mono recording on CD either has one empty channel, or else the same signal being relayed to both channels simultaneously. However, noncommercial CD's in other formats such as White Book or Orange Book can feature up to four hours of stereo music on one CD for the purposes of extended programming in public spaces, such as malls.
These formats slightly reduce both the sampling frequency from 44.1 kHz as well as the bit-depth frequency from 16-bit and employ other proprietary technologies in order to increase the time on the disc and, as in the 16-inch transcriptions above - render them unplayable on the vast majority of consumer equipment.
Read more about this topic: Stereophonic Sound
Famous quotes containing the words compact and/or disc:
“... in a history of spiritual rupture, a social compact built on fantasy and collective secrets, poetry becomes more necessary than ever: it keeps the underground aquifers flowing; it is the liquid voice that can wear through stone.”
—Adrienne Rich (b. 1929)
“Soundless as dots—on a Disc of Snow—”
—Emily Dickinson (1830–1886)