A portable audio player is a personal mobile device that allows the user to listen to recorded
audio Audio most commonly refers to sound, as it is transmitted in signal form. It may also refer to: Sound *Audio signal, an electrical representation of sound *Audio frequency, a frequency in the audio spectrum *Digital audio, representation of sound ...
while mobile. Sometimes a distinction is made between a ''portable'' player, battery-powered and with one or more small
loudspeaker A loudspeaker (commonly referred to as a speaker or speaker driver) is an electroacoustic transducer that converts an electrical audio signal into a corresponding sound. A ''speaker system'', also often simply referred to as a "speaker" or " ...
s, and a ''personal'' player, listened to with
earphone Headphones are a pair of small loudspeaker drivers worn on or around the head over a user's ears. They are electroacoustic transducers, which convert an electrical signal to a corresponding sound. Headphones let a single user listen to an a ...


Portable battery-operated
reel-to-reel tape recorder Reel-to-reel audio tape recording, also called open-reel recording, is magnetic tape audio recording in which the recording tape is spooled between reels. To prepare for use, the ''supply reel'' (or ''feed reel'') containing the tape is plac ...
s were introduced in the 1950s, initially tending to be high-priced units for reporters, produced by Uher and
Nagra Nagra is a brand of portable audio recorders produced from 1951 in Switzerland. Beginning in 1997 a range of high-end equipment aimed at the audiophile community was introduced, and Nagra expanded the company’s product lines into new markets. ...
. Lower-priced units became available later. In the mid-1960s
Philips Koninklijke Philips N.V. (), commonly shortened to Philips, is a Dutch multinational conglomerate corporation that was founded in Eindhoven in 1891. Since 1997, it has been mostly headquartered in Amsterdam, though the Benelux headquarters is ...
introduced the battery-operated
compact cassette The Compact Cassette or Musicassette (MC), also commonly called the tape cassette, cassette tape, audio cassette, or simply tape or cassette, is an analog magnetic tape recording format for audio recording and playback. Invented by Lou Otte ...
recorder, originally used for recording speech. At about the same time the 8-track player was introduced. It was very successful at the time, though bulky and inconvenient to use. There was a pause at the end of each track as the program changed. The compact cassette, although physically much smaller than the 8-track cartridge, became capable of good sound quality as the technology developed, and longer cassette tapes became available. Cassette decks (not portable) were introduced for home use, and this encouraged the production of pre-recorded music cassettes.

Personal stereo

The first truly personal
cassette player A cassette deck is a type of tape machine for playing and recording audio cassettes that does not have a built-in power amplifier or speakers, and serves primarily as a transport. It can be a part of an automotive entertainment system, a part of a ...
, the Sony Walkman, was introduced in 1979 and sold very well. It was much smaller than an 8-track player or the earlier cassette recorders, and was listened to with stereophonic
headphones Headphones are a pair of small loudspeaker drivers worn on or around the head over a user's ears. They are electroacoustic transducers, which convert an electrical signal to a corresponding sound. Headphones let a single user listen to an au ...
, unlike previous equipment which used small loudspeakers. Unlike small loudspeakers, headphones were capable of very good sound quality. All previous compact cassette devices could record as well as play back; Walkmans and similar devices often had no recording facility, but took advantage of the pre-recorded cassettes that had become widely available.

Disk players

Early personal CD players can play commercial CDs; later models can play recordable
CD-R CD-R (Compact disc-recordable) is a digital optical disc storage format. A CD-R disc is a compact disc that can be written once and read arbitrarily many times. CD-R discs (CD-Rs) are readable by most CD readers manufactured prior to the int ...
and CDRW media either copied from a pressed CD or containing MP3 and similar files.

Media players

In 1998, digital audio players (DAPs) based on
flash memory Flash memory is an electronic non-volatile computer memory storage medium that can be electrically erased and reprogrammed. The two main types of flash memory, NOR flash and NAND flash, are named for the NOR and NAND logic gates. Both use t ...
hard disk A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magnet ...
storage became available (The Rio PMP300 from Diamond Multimedia is widely considered to be the first mass market DAP). Files are usually compressed using
lossy compression In information technology, lossy compression or irreversible compression is the class of data compression methods that uses inexact approximations and partial data discarding to represent the content. These techniques are used to reduce data siz ...
; this reduces file size at the cost of some loss of quality. The
trade-off A trade-off (or tradeoff) is a situational decision that involves diminishing or losing one quality, quantity, or property of a set or design in return for gains in other aspects. In simple terms, a tradeoff is where one thing increases, and anot ...
between degree of compression and file size can be varied, although this is not an option for existing compressed files. The advantage of solid-state DAPs over hard disks and CDs is resistance to vibration, small size and weight, and low battery usage. Early solid-state DAPs had capacities of a few tens of kilobytes; capacities of many gigabytes are available.

Further reading

* Erlmann, Veit (ed.
''Hearing Cultures. Essays on Sound, Listening, and Modernity''
New York: Berg Publishers, 2004. Cf. Chapter 9: "Thinking About Sound, Proximity, and Distance in Western Experience: The Case of Odysseus's Walkman" by Michael Bull.

See also

* Waterproof audio player