Science Fair Project Encyclopedia
Digital audio player
A digital audio player (DAP) is a device that stores, organizes and plays digital music files. It is more commonly referred to as an MP3 player (because of that format's ubiquity), but DAPs often play many additional file formats. Some formats are proprietary, such as MP3, Windows Media Audio (WMA), and Advanced Audio Codec (AAC). Some of these formats also may incorporate digital rights management (DRM), such as WMA DRM, which are often part of paid download sites. Other formats are patent-free or otherwise open, such as Vorbis, FLAC, and Speex (all part of the Ogg open multimedia project).
The first digital audio player on the American market was the Eiger Labs F10, a 32MB portable that appeared in the summer of 1998. It was a very basic unit and wasn't user expandable, though owners could upgrade the memory to 64MB by sending the player back to Eiger Labs with a check for $69 + $7.95 shipping.
The second DAP was the Rio PMP300 from Diamond Multimedia , introduced in September 1998. The Rio was a big success during the Christmas 1998 season as sales significantly exceeded expectations, spurring interest and investment in digital music. The Recording Industry Association of America soon filed a lawsuit alleging that the device abetted illegal copying of music, but Diamond won a legal victory on the shoulders of Sony Corp. v. Universal City Studios and digital audio players were ruled legal devices.
Other early DAPs includes Sensory Science's Rave MP2100, the I-Jam IJ-100, and the Creative Labs Nomad. These portables were small and light, but only held enough memory to hold around 7 to 20 songs at normal 128 kbit/s compression rates. They also used slower parallel port connections to transfer files from PC to player, necessary as most PCs then used the Windows 95 and NT operating systems, which did not support the then newer USB connections well enough to be considered for use. As more users migrated to Windows 98 by the year 2000, most (if not all) players went USB.
At the end of 1999, a company called Remote Solutions made a significant improvement in DAPs' space limitations by utilizing a laptop hard drive for song storage rather than low-capacity flash memory. The Personal Jukebox (PJB-100) had 4.8GB of storage space, which held about 1200 songs (or 100 CDs, hence the name PJB-100), and was the beginning of what would be called the jukebox segment of digital audio players. This segment eventually became the dominant type of DAP.
Also, at the end of 1999, the first in-dash digital audio player appeared. The Empeg Car (renamed the Rio Car after it was acquired by SonicBLUE and added to its Rio line of MP3 products) offered players in several capacities ranging from 5GB to 28GB. The unit didn't catch on as SonicBLUE had hoped, however, and was discontinued in the fall of 2001.
There are three main segments of digital audio players:
- MP3 CD Players - Devices that play CDs. Often, they can be used to play both audio CDs and homemade data CDs containing MP3 or other digital audio files.
- Flash-based Players - These are solid state devices that hold digital audio files on internal or external media, such as memory cards. These are generally low-storage devices, typically ranging from 128MB-1GB, which can often be extended with additional memory. As they are solid state and do not have moving parts, they can be very resilient. Such players are generally integrated into USB keydrives.
- Hard Drive-based Players or Digital Jukeboxes - Devices that read digital audio files from a hard drive. These players have higher capacities, ranging from 1.5GB to 100GB, depending on the hard drive technology. At typical encoding rates, this means that thousands of songs — perhaps an entire music collection — can be stored in one MP3 player. The Apple iPod and Creative Zen are examples of popular digital jukeboxes.
Generally speaking, digital audio players are portable, employing internal or replaceable batteries and headphones, although users often connect players to car and home stereos — sometimes via a wireless connection — thereby turning them into portable jukeboxes. Some DAPs also include FM radio tuners . Many players can encode audio directly to MP3 or other digital audio formats directly from a line in audio signal.
Devices such as CD players can be connected to digital audio players (using the USB port) in order to directly play music from the memory of the player without the use of a computer.
Modular keydrive players are composed of two detachable parts: the head (or reader/writer) and the body (the memory). They can be independently obtained and upgraded (one can change the head or the body; i.e. to add more memory).
Brands of digital audio players
- iPod from Apple
- Joybee from BenQ
- Dell Digital Jukebox ("Dell DJ") series from Dell
- Creative Nomad/Creative Zen line of MP3 players from Creative Labs
- IRiver players by IRiver
- MP3 Player database - Non profit organisation to catalogue all mp3 players
- Collecting MP3 Portables -- Part I - Richard Menta's article covers several of the first MP3 players on the market. With pictures of each player.
- MP3 Player Guide - information on the latest MP3 players
- Portable MP3 Players - features individual player overview and the history of portable MP3 players
- Podcasting News - info on using MP3 players to receive podcasts
- repair and upgrade instructions for portable audio and video players
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