tapes were also used for easy transport of filmed scenes for dailies in the days before VHS, DVD, and portable hard drives. Several movies have surviving copies in this form. The first rough cut of Apocalypse Now, for example (the raw version of what became Apocalypse Now Redux), survived on three U-Matic cassettes. Audio quality was compromised due to the use of longitudinal audio tape heads in combination with slow tape speed. Sony eventually implemented Dolby noise reduction circuitry (using Dolby C) to improve audio fidelity. The 2012 film No, set in 1980s Chile, used U-matic tape for filming. Digital audio U-matic was also used for the storage of digital audio data. Most digital audio recordings from the 1980s were recorded on U-matic tape via a Sony PCM-1600, -1610, or -1630 PCM adaptor. These devices accepted stereo analogue audio, digitised it, and generated "pseudo video" from the bits, storing 96 bits—three stereo pairs of 16-bit samples—as bright and dark regions along each scan line. (On a monitor the "video" looked like vibrating checkerboard patterns.) This could be recorded on a U-matic recorder. This was the first system used for mastering audio compact discs in the early 1980s. The famous compact disc 44.1 kHz sampling rate was based on a best-fit calculation for PAL and monochrome NTSC video's horizontal line period and rate and U-matic's luminance bandwidth. On playback, the PCM adapter converted the light and dark regions back into bits. Glass masters for audio CDs were made via laser from the PCM-1600's digital output to a photoresist- or dye-polymer-coated disc. This method was common until the mid-1990s. Decline of use U-matic is no longer used as a mainstream television production format, but it has found lasting appeal as a cheap, well specified, and hard-wearing format. The format permitted many broadcast and non-broadcast institutions to produce television programming on an accessible budget, spawning programming distribution, classroom playback, etc. At its peak popularity, U-matic recording and playback equipment was manufactured by Sony, Panasonic, JVC and Sharp, with many spin-off product manufacturers, such as video edit controllers, time base correctors, video production furniture, playback monitors and carts, etc. Many television facilities the world over still have a U-matic recorder for archive playback of material recorded in the 1970s and 1980s. For example, the Library of Congress facility in Culpeper, Virginia, holds thousands of titles on U-matic video as a means of providing access