Introduction
Beginnings
Analogue v Digital
Compact Disc
WAV File Format
MP3 File Format
Other File Formats
Digital Music

Introduction

If you're reading this page, the chances are you already know a bit about digital music, which is basically the storage of music in a digital format for reading and playback through a computer, CD player, iPod or other digital device.

On this page, John Dalling takes a look at the history of digital music.

Beginnings

In 1877, Thomas Edison created the first device capable of recording and playing back sound, called a "phonograph". This was simply a needle which scratched an analogue wave onto a cylinder made of tin foil. This device formed the basis of the gramophone, which improved on Edison's original idea by using flat records rather than a cylinder. Essentially, today's decks / record players are nothing more than a sophisticated version of this device.

Analogue v Digital

Analogue recording produces a copy of the actual soundwave produced by a noise or sound. In an ideal world, this would provide an exact copy of the sound being recorded, which is why some people believe vinyl produces a higher quality of recording than a CD. In reality, however, the methods used to record and play back analogue music mean that the recording is not an exact replica of the original sound. Any tiny scratches or dust on the surface of a vinyl record, for example, create tiny imperfections in the sound, which is why the more records are used, the more they are likely to deteriorate. There is also a limit to the frequencies used during analogue recording, especially at the high and low ends.

Digital recording does not produce an exact copy of the soundwave being recorded. Instead, a digital recording takes minute "samples" of a sound at a specified rate and converts these into digital data (digital because the binary digits 0 and 1 are used). To play back a digital recording, the player uses these samples to build up a soundwave. This is why some people argue that analogue recording is better quality, in theory: in a digital recording, the remaining soundwave other than the "samples" is lost. In modern digital music, however, so many samples of the soundwave are taken that, on playback, the difference between the digital sound and the original sound is usually inaudible to the human ear.

The Compact Disc

The first practical application of digital music recording came with the compact disc (CD). The CD was developed in 1979 by Philips and Sony (the same year that the walkman was first commercially available, and that the first rap record, "Rapper's Delight" by the Sugarhill Gang, hit the UK Top 40). Philips were behind the manufacturing of the CD, which was initially 60 minutes long until Sony insisted on the standard 74 minute length. The 74 minute capacity determined the size of the disc - 120mm.

The CD was first manufactured commercially in 1982, but it wasn't until the early 1990s that the sales of CDs overtook that of vinyl records in the United Kingdom. While initially the price and availability of CDs led them to rival vinyl records, the long term impact of their success has been to drastically reduce sales of the audio cassette. This was partly due to the revival of vinyl, thanks to the DJ and mixing culture of the 1990s. Until very recently, CD mixers were harder to use and more expensive to manufacture than turntables.

The standard ("Red Book") format of a CD was introduced by Philips. This format allows 16-bit stereo encoding at a sample rate of 44.1kHz. The 44.1kHz figure means the data gives 44100 samples per second, which derives from video recording standards. Until relatively recently, all CDs were 74 minutes or under; manufacturing advances have led to CDs of 80 minutes becoming widely available.

In 1985, the CD-ROM standard ("Yellow Book") for computer data was developed. By creating a disc which could be used to store either music or data, Philips and Sony had created a standard which was to lead to the popularity of the CD during the next decade and beyond.

During the 1990s, CD writers became popular, using special CDR and CDRW discs, which are manufactured in a different way to standard audio CDs and CD-ROMs. Following the rise of CD writers, "copy protected" CDs were introduced by some record companies in 2002, although these have had varying degrees of success to date.

Alternatives to the CD were also developed in the 1980s and 1990s. These include the DAT (Digital Audio Tape), the Minidisc and the Mini-CD. DAT found favour with recording engineers and studios as a standard prior to the availability of cheap hard disk recording and CDRs, but never really reached the home user marker. The Minidisc did reach the home user and had some success during the late 1990s. Minidiscs are smaller and more robust than standard CDs, and are re-recordable like cassettes. However, the Minidisc was unlucky with its timing; it was reaching popularity just as the MP3 boom was beginning and recordable CD players were reaching the commercial market.

WAV File Format

The standard WAV (or WAVE) format was created by Microsoft and IBM for the storage of audio on PCs. Macintosh computers use the Mac standard AIFF file format. In the early days of personal computing, these formats were alone used for playing back sound on a computer. On early PCs, however, sound was mainly used to enhance software; to reinforce error messages with a "bleep", for example. As WAV sound files are very large compared to most other forms of data (e.g. images, text) personal computer users weren't able to take advantage of good quality music on their machines in the early days of home computing.

WAV files are most commonly compressed using the PCM codec. This retains all the samples from the original digital recording, making WAV files a popular choice for high quality audio recording. Due to their large file size, WAV music files have never been popular for online music despite their potential quality.

These days, WAV as a music format is mainly the reserve of music producers and recording professionals, who wish to retain maximum file quality. A major advantage of the WAV format is that it is supported by a vast number of audio editors and music software programs, making it the standard for creating and manipulating digital music rather than for listening to the end result.

MP3 File Format

The MP3 format was developed by the Fraunhofer Institut Integrierte Schaltungen research centre in Germany. In 1987, the Fraunhofer Institut began work on EUREKA project EU147 - Digital Audio Broadcasting (DAB), a project which was aimed at researching high quality audio encoding and ran until 1994. Meanwhile, in 1988 the Moving Picture Experts Group (MPEG for short) was established by the Industry Standards Organization (ISO).

In 1992, the MPEG-1 video compression standard was finalised by the ISO. Further advances led to MPEG-2 which was finalised in 1994. MPEG-2 became used with the introduction of the DVD. MP3 is actually a subset of the MPEG-1 standard, and is short for "MPEG-1 Audio Layer III". MP3 was devised separately by Fraunhofer as part of the EU147 project and integrated into the MPEG-1 standard.

In 1995, MP3 files began to appear on the internet, and by November 1996 Fraunhofer had been granted the patent for MP3 in the USA. By the end of 1998, Fraunhofer had requested that companies producing MP3 players and encoders apply to them for licences.

Generally speaking, an MP3 file can be around 10 times smaller than its WAV equivalent, although the actual file size will depend on the bitrate and encoder being used.

Other File Formats

The first version of the RealAudio file format was released in 1995 by RealNetworks. The main player used for these files is the RealPlayer, also produced by RealNetworks. The RealAudio format was designed to work well at low bandwidths, and is a common choice for streaming files (i.e. files which are played as they are being downloaded, rather than saved). RealAudio files use the extensions .ram .ra or .rm.

Windows Media Audio (WMA) is a file format developed by Microsoft. WMA was intended to rival the MP3 file, and as such it supports constant and variable bit rates. WMA also now supports digital rights management. WMA files can rival MP3 files for quality and small file size, and the latest version of WMA can also support surround sound.

Digital Music Online

MPEG-1 Audio Layer II files (MP2) were reported as first appearing on the internet in autumn 1993. At this time, MP2 files could only be encoded by a program called Xing. Rob Lord and Jeff Paterson from the University of California started the Internet Underground Music Archive, or IUMA for short, in 1993. IUMA was the first dedicated high quality music website, and hosted tracks encoded as MP2 files.

MP3 files first appeared on the internet around 1995. At this time, internet connection speeds and computer processing speeds limited the number of people who could take full advantage of this new file format. By the end of the decade, however, this was beginning to change, and in 1997 MP3.com and Soundclick were launched as a platform for artists seeking to promote their music online.

The technology was slowly coming together at the end of the 1990s to allow online music to reach a wider audience. With internet connection speeds, computer processing power and hard disk sizes all steadily rising, while new audio formats allowed music file sizes to decrease, the online world became ready to embrace digital music.

MP3 exploded into the public eye in 1999 when Shawn Fanning and Sean Parker launched the original Napster, a piece of software designed to allow users to share MP3 files on the internet. Napster worked by analysing the user's hard disk for music files and then connecting to a server to allow other Napster users to view and download them. This caused chaos in the music industry, as people began to download tracks and whole albums without paying for them. Rival programs to Napster soon sprung up, and after much discussion about how to handle this new phenomenon the music industry began to take action against prolific file users in 2000.

Napster was closed down by the authorities in 2001, and slowly but surely legal music downloading began to emerge. Legal pioneers include Apple, whose iTunes website was designed specifically to work with its own iPod product. Other sites sprung up in 2003 and 2004 including MyCokeMusic (from Coca Cola) and Tesco Downloads (from none other than supermarket giant Tesco), as well as the relaunched, and now legal, Napster.

The rise of digital music goes hand in hand with the rise of the computer-based CD burner. Before the rise of portable MP3 players and the iPod, the easiest way to play the MP3 tracks you'd downloaded offline was to burn them onto a CD.

With an influx of new, legal music websites, broadband internet access and the emergence of portable digital music players, there came a new problem - the official charts didn't take account for online music downloads. Enter the Official UK Download Chart, launched on 1st September 2004. The first ever number one was by Westlife, an Irish boyband - showing that from its underground roots, digital music had indeed finally reached the mainstream. On the 17th April 2005, the UK singles Top 40 incorporated downloads for the first time, with download figures counting for nearly half of all singles sales by this time.

© John Dalling, 2006

While every attempt is made to ensure the information on this page is correct, the author cannot accept responsibility for the accuracy of the information provided.