Mercedes-Benz 2009 CL-Class Automobile User Manual


 
COMAND audio CD/audio DVD/MP3
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to access the audio CD tracks. Access to the
MP3/WMA tracks is not possible.
Similarly, if the first session type is according
to the data CD standard containing MP3/
WMA tracks and the second session type is
according to the audio CD standard,
COMAND will treat the CD as a data CD. This
means that it is only possible to access the
MP3/WMA tracks. Access to the audio CD
tracks is not possible.
File structure on a disc
When you create an MP3/WMA disc, the
MP3/WMA tracks can be organized in
folders. A folder can also contain other
folders. A disc can contain a maximum of
255 folders. Each folder can contain a
maximum of 255 tracks and 255 folders. A
data medium may contain a maximum of 500
tracks.
Track and folder names
When you create an MP3/WMA disc, you can
assign names to the MP3/WMA tracks and
folders.
COMAND uses these names for the
corresponding display in MP3 mode. Empty
folders or folders which contain data other
than MP3/WMA tracks are not displayed by
COMAND.
If MP3/WMA files are saved in the root
directory itself (uppermost directory on
storage medium), the root directory will also
be treated as a folder. COMAND will then
show the name of the root directory as the
folder name.
You must observe the following when
assigning track names:
R
Track names must have at least one
character.
R
Track names must have the extension
“mp3” or “wma”.
R
There must be a period between the track
name and the extension.
Example of a correct track name:
Track1.mp3
COMAND is unable to recognize an MP3/
WMA track if:
R
there is no period between the track title
and the extension
R
there is no extension
i
COMAND does not support ID3 tags.
Compatible file systems and
compression methods
The following compression methods are
compatible:
R
MP3
R
WMA
i
If music files created using different
compression methods other than MP3 are
stored together on a disc, the loading
process may take longer.
Permissible MP3 formats
COMAND supports the MPEG1 Audio Layer 3
format.
i
This format is generally known as “MP3”.
Permissible bit and sampling rates
R
Fixed and variable bit rates up to
320 kbit/s
R
Sampling rates from 24 kHz to 48 kHz
i
Only use MP3 tracks with a bit rate of at
least 128 kbit/s and a sampling rate of at
least 44.1 kHz. Smaller rates can cause a
noticeable deterioration in sound quality.
Control systems