Operation Manual

Glossary
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Glossary
AAC
Advanced Audio Coding (AAC) is one of the audio compression formats defined by the MPEG-2 specification.
AAC used to be called NBC (Non-Backward-Compatible), because it is not compatible with the MPEG-1 audio
formats. AAC may eventually replace MP3 since it offers better sound quality and greater file compression.
Bitrate, file compression
Bitrate denotes the average number of bits that one second of audio data will consume. The size of a digital audio
file is determined by the bitrate used when encoding the file. The higher the bitrate used, the higher the sound
quality and the larger the file size. For example, for MP3s a bitrate of 128k is usually very close to CD quality,
and takes up about 1MB per minute of music. At a 64k bitrate, the MP3 sound quality is similar to that of an FM
radio signal, but you may get around two minutes of music in that same 1MB of storage space.
Codec
Depending on the context and kind of technology involved, codec may be defined in two ways.
In telecommunications, a codec is usually a "coding/decoding" chip used to translate between digital and analog
transmissions. A modem uses one to interpret incoming analog signals and converts the digital data stream
coming from the computer into analog.
A codec is also defined as a compression/decompression algorithm. Codecs are used to shrink large files or data
streams, often for efficient transmission over a network, and then decode them when they are displayed.
The RioVolt supports the following digital audio file codecs:
•MP3
•WMA
DRM, security
Digital Rights Management (DRM) technologies protect copyright ownership of digital information. DRM
became an issue with the rise of MP3 technology and Internet distribution of music. DRM platforms serve as a
security “wrapper” around digital audio supporting Internet distribution while at the same time protecting and
managing rights related to that digital information.
Encode, “Rip” (a CD)
Encoding, or “ripping”, refers to converting an audio file from a CD-ROM into a compressed digital audio
format, such as MP3 or WMA, that may be played on the RioVolt, on the computer, or on a portable Rio Digital
Audio Player.
Gracenote
Formerly known as CDDB, Gracenote is an vast database of CD information that includes disc name, song titles
and other information. Gracenote supports hundreds of third party software CD players. Access to the Gracenote
service is offered free of charge to end-users. Visit the Gracenote website for more information.