Introduction
More commonly referred to as an MP3 player, a digital audio player
("DAP") is a portable consumer electronics device that stores,
organizes and plays audio files. Some DAPs are also referred as
portable media players as they have image-viewing and/or video-playing
support. Most DAPs are powered by rechargeable batteries, some of which
are not user replaceable. Listening to music stored on DAPs is
typically through earphones connected with a 3.5 mm jack.
Digital audio players are generally categorized by storage media:
- Flash-based
Players – These are non mechanical solid state
devices that hold digital audio files on internal flash memory or
removable flash media called memory cards. Due to technological
advancements in flash memory, these originally low-storage devices are
now available commercially ranging up to 32 GB.[1] Because they are
solid state and do not have moving parts they require less battery
power and may be more resilient to hazards such as dropping or
fragmentation than hard disk-based players. Basic MP3 player functions
are commonly integrated into USB flash drives.
- Hard
drive-based Players or Digital Jukeboxes –
Devices that read digital audio files from a hard disk drive (HDD).
These players have higher capacities currently ranging up to 250 GB.[2]
At typical encoding rates, this means that thousands of songs
– perhaps an entire music collection – can be
stored on one player.
- MP3 CD
Players – Portable CD players that can decode
and play MP3 audio files stored on CDs
History
The predecessors to digital audio players are portable CD and MiniDisc
players, which are commonly known as "Portable Audio Devices". Although
the data is digitally stored on discs, neither one is able to support
digital file formats.
The first mass-produced DAP was created in 1997 by SaeHan Information
Systems, which domestically sold its “MPMan” player
in the middle of 1998.[3] The South Korean company then licensed the
players to Eiger Labs which distributed them - now branded as Eiger
Labs MPMan F10 - to the North American market during the summer of
1998.[4] The flash-based players were available in 32 MB storage
capacity.
The Rio PMP300 from Diamond Multimedia was introduced in September
1998, a few months after the MPMan. It was a success during the holiday
season, with sales exceeding expectations.[5] Interest and investment
in digital music were subsequently spurred from it.[6] The Recording
Industry Association of America (RIAA) soon filed a lawsuit,[7]
alleging that the device encouraged copying music illegally, but
Diamond won a legal victory on the shoulders of the Sony Corp. v.
Universal City Studios case and DAPs were legally ruled as electronic
devices.[8] Because of the player's notoriety as the target of a major
lawsuit, the Rio is erroneously assumed to be the first DAP.[9]
In 1998, Compaq made the first hard drive based DAP using a 2.5" laptop
drive. It was licensed to HanGo Electronics (now known as Remote
Solution), which first sold the PJB-100 (Personal Jukebox) in 1999. The
player had an initial capacity of 4.8 GB, which was advertised to be
able to hold 1200 songs.[10]
In October 2001, Apple Computer (now known as Apple Inc.) unveiled the
first generation iPod, the 5 GB hard drive based DAP with a 1.8"
Toshiba drive. Having focused on developing an intuitive user
interface, the smaller form factor and industrial design made the
player notable within users of the Macintosh community. In July 2002,
Apple introduced the second generation update to the iPod. It was
compatible with Windows computers through Musicmatch Jukebox (now known
as Y!Music Musicmatch Jukebox). The iPod series, which grew to include
microdrive and flash-based players, has become the market leader in
DAPs.
In 2002, Archos released the first official PMP, the Archos Jukebox
Multimedia.[11] Manufacturers have since implemented abilities to view
images and play videos into their devices.
Although online music services such as RealNetworks’ Rhapsody
offered legal downloads through a subscription plan, the launch of the
iTunes Store in 2003 established the model of selling individual songs
for purchase.
Audio
acquisition
All commercially available digital audio players can play music that
has been ripped from Compact Discs via computer. In addition to ripped
CD tracks, many digital audio players can accept downloaded music from
online music stores. However, such stores often use proprietary formats
and DRM, which means that the tracks can only be played on suitably
licensed and restricted devices. For example, purchased songs from
iTunes might not work on any DAP other than an Apple iPod.
There are also music online communities such as GarageBand.com where
music is available at no cost under Creative Commons licenses.
Another way of getting audio files is to rip the songs from radio
broadcasts. Many players have the ability to record songs played on the
built-in FM tuner. Recently, a Swedish company called PopCatcher has
developed a technology to save songs from Internet radio and can
distinguish between songs, DJ talks, and commercials for convenience.
Common
formats supported
MP3 is the dominant format, and is nearly universally supported.[12]
The main alternative formats are AAC, supported on players from Apple,
ATRAC, on players from Sony, and WMA, on players from Microsoft and
partners. Unlike MP3, these formats support DRM restrictions, which are
often added to files from paid download services. Open source formats
which are completely patent-free are available but less widely
supported – examples include Ogg Vorbis, FLAC, Speex, and
Module file formats.
Controversy
Although these issues aren't usually controversial within digital audio
players, they are matters of continuing controversy and litigation,
including but not limited to content distribution and protection, and
digital rights management (DRM).