Operation Manual

Page 25
Digital audio terms
MP3
MPEG-1, Layer 3 Audio (MP3) is a compressed digital audio file format. This format allows
for near CD-quality sound, but at a fraction of the size of normal audio files. MP3 conversion
of an audio track from CD-ROM reduces the file size by approximately a 12:1 ratio with
virtually no loss in quality. This digital sound encoding and compression process was
developed by the Fraunhofer Institut für Integrierte Schaltungen and Thomson Multimedia.
MP3 uses perceptual audio coding and psychoacoustic compression to remove the
redundant and irrelevant parts of a sound signal that the human ear does not hear. It also
adds a Modified Discrete Cosine Transform (MDCT) that implements a filter bank, increasing
the frequency resolution to 18 times higher than that of layer 2. The MP3 encoding process is
well suited for the transfer of high quality audio files with small file size over the Internet.
Playlist
Playlists let you organise lists of tracks to play in the order you choose. Playlists make it
easier to manage large collections of music.
Ripping
See Encoding.
SDMI
The Secure Digital Music Initiative (SDMI) is a forum of over 130 companies in the fields of
recorded audio content, computers, and consumer electronics, for the purpose of developing
an integrated method of copyright protection technology that can be used worldwide. SDMI is
working to create a framework for preventing improper usage of audio files and to promote
legal music distribution services.
Skin
The skin is the software option that determines how digital audio player software applications
appear on your computer screen. Some applications allow you to customise the colour and
window design of your software by changing the skin. Some skins omit certain playback
controls for simplicity.
USB
Universal Serial Bus (USB) is the external bus standard that supports data transfer rates of
12 Mbps (12 million bits per second). The Rio uses USB to communicate with the computer.
A single USB port may be used to connect up to 127 peripheral devices, such as mice,
modems, and keyboards. USB also supports Plug-and-Play installation and hot plugging. It is
expected to completely replace serial and parallel ports.
WMA
Windows Media Audio (WMA) is the compressed audio format created by Microsoft as a
alternative to MP3. WMA may replace MP3 since it offers greater file compression—twice
that of MP3—at the same or better sound quality.