About Encoded Audio; Variable Bitrate - Nokia N73-5 User Manual

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To restore the original album art, select
original.

About encoded audio

Applications like Windows Media Player, and Nokia Audio
Manager (included in the Nokia PC Suite) encode audio
files with codecs such as WMA or MP3 to save storage
space. The encoding is done by removing those parts of the
audio signal that are not audible or only barely audible by
human ear.
Regardless of the encoder and codec quality, the sound
quality of the resulting file is not as good as the original.
The basic codecs supported by this device are AAC, WMA,
and MP3. All of these have different variations.
Bitrates
When encoding audio, the quality of the resulting sound
depends on the sample rate and bit rate used for the
encoding. Sample rate is expressed as thousands of
samples per second (kHz), and for CD music the sample
rate is fixed at 44.1 kHz. Bit rate is expressed as kilobits per
second (Kbps). The higher the bitrate, the better the sound
quality.
Restore The required quality level may depend on your demands,
the headsets used, and the surrounding noise. For MP3s a
bitrate between 128 and 192 Kbps usually gives results
good enough for listening to pop music with your device.
WMA or AAC generally gives a similar result as MP3 with
one step lower bitrate (96-160 Kbps). Variations of AAC,
such as AAC+ and enhanced AAC+ (eAAC+) provide CD
quality audio at bitrates as low as 48 Kbps. Classical music
and music with nuances usually require a higher bitrate
than basic pop music.
For speech or other sources where the quality of the sound
is less important than saving storage space, you can use
bitrates between 8 and 64 Kbps. At low bitrates WMA or
AAC generally gives better results than MP3.

Variable bitrate

Your device also supports variable bitrate (VBR).
Variable bitrate means that the bit rate of the encoding
varies with the complexity of the encoded material.
When using VBR, the encoding is optimized to preserve a
constant audio quality throughout the track, rather than
losing quality for complex music sections as with constant
bitrate (CBR) encoding.
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