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Information, About mp3/wma – Alpine cda-9805 User Manual

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Information

About MP3/WMA

CAUTION
Except for personal enjoyment, duplicating audio data
(including MP3/WMA data) or distributing, transferring,
or copying it, whether for free or for a fee, without the
permission of the copyright holder is strictly prohibited
by the Copyright Act and by international treaty.

What is MP3?

MP3, whose official name is “MPEG Audio Layer 3”, is a
compression standard prescribed by the ISO, the
International Standardization Organization and MPEG
which is a joint activity institution of the IEC.

MP3 files contain compressed audio data. MP3 encoding
is capable of compressing the audio data at extremely
high ratios shrinking music files by as much as one-tenth
their original size. This is achieved while still maintaining
near CD quality. The MP3 format realizes such high
compression ratios by eliminating the sounds that are
either inaudible to the human ear or masked by other
sounds.

What is WMA?

WMA, or “Windows Media™ Audio,” is compressed audio
data.
WMA allows you to create music files and store them at
higher ratios of compression than MP3 audio data
(approx. half original size). This is achieved while still
maintaining CD quality sound.

Method for creating MP3/WMA files

Audio data is compressed by using MP3/WMA specified
software. For details on creating MP3/WMA files, refer to
the user's manual for that software.
The MP3 files that can be played back by this device
have the file extension “mp3”. Files with no extension can
not be played back.
WMA files have the "wma" extension.
(WMA ver. 7.1 and 8 are supported)

Supported playback sampling rates and bit rates

MP3
Sampling rates: 48 kHz, 44.1 kHz, 32 kHz, 24 kHz, 22.05

kHz, 16 kHz, 12 kHz, 11.025 kHz, 8 kHz,

Bit rates:

8 - 320 kbps

WMA
Sampling rates: 48 kHz, 44.1 kHz, 32 kHz, 24 kHz,

22.05 kHz

Bit rates:

32 - 192 kbps

Note that for sampling rates, this device’s frame display
(Page 9) may not display correctly.
This device may not play back correctly depending on
sampling rates.

ID3 tags/WMA tags

ID3 tags of this device support ID3 tag v1 and v2.
If ID3 tag/WMA tag data is in an MP3/WMA file, this
device can display the title (track title), artist name, and
album name ID3/WMA tag data.

This device can only display single-byte alphanumeric
characters (up to 30) and the underscore. For non-
supported characters, “NO SUPRT” is displayed.

Producing MP3/WMA discs

MP3/WMA files are prepared, then written to a CD-R or
CD-RW using CD-R writing software. A disc can hold up
to 512 files/folders (including Root Folders).

Media supported

The media that this device can play back are CD-ROMs,
CD-Rs, and CD-RWs.

Corresponding File Systems

This device supports discs formatted with ISO9660 Level
1 or Level 2.

Under the ISO9660 standard,
there are some restrictions to remember.
The maximum nested folder depth is 8 (including the
root directory). File/folder names are limited to 31
characters (including the extension), and are limited to
15 characters for WMA.
Valid characters for folder/file names are letters A-Z (all
caps), numbers 0-9, and ‘_’ (underscore).

This device also can play back discs in Joliet, Romeo,
etc., and other standards that conform to ISO9660.
However, sometimes the file names, folder names, etc.
are not displayed correctly.

Formats supported

This device supports CD-ROM XA, Mixed Mode CD,
Enhanced CD (CD-Extra) and Multi-Session.
This device can not correctly play back discs recorded
with Track At Once or packet writing.