Alpine IDA-X303 - Manual (Page 19)

17
-EN
About MP3/WMA/AAC
What is MP3?
MP3, whose official name is “MPEG-1 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 audio data at extremely high ratios,
reducing the size of music files to 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 AAC?
AAC is the abbreviation for “Advanced Audio Coding,” and is a
basic format of audio compression used by MPEG2 or MPEG4.
What is WMA?
WMA, or “Windows Media™ Audio,” is compressed audio data.
WMA is similar to MP3 audio data and can achieve CD quality
sound with small file sizes.
Method for creating MP3/WMA/AAC files
Audio data is compressed by using MP3/WMA/AAC specified
software. For details on creating MP3/WMA/AAC files, refer to
the user’s manual for that software.
MP3/WMA/AAC file extensions that can be played back on the
unit are as follows:
MP3: “mp3”
WMA: “wma” (ver. 7.1, 8, 9, 9.1, 9.2 supported)
AAC: “m4a”
WMA is not supported for the following files, Windows Media
Audio Professional, Windows Media Audio 9 Voice or Windows
Media Audio 9 Pro Lossless.
Depending on the software that is used to create AAC, the file
format may differ from the extension.
Playback of AAC files encoded by iTunes is supported.
Supported playback sampling rates and bit rates
MP3
WMA
AAC
This device may not play back correctly depending on sampling
rates.
The playback time may not be correctly displayed when a VBR
(Variable Bit Rate) recorded file is played back.
ID3 tags/WMA tags
This device supports ID3 tag v1 and v2.2.0, v2.3.0 and WMA
tag. The following files do not support compression, coding,
grouping or non-synchronization.
If tag data is in an MP3/WMA/AAC file, this device can display
the title (track title), artist name, and album name ID3 tag/WMA
tag data.
This device can only display single-byte alphanumeric
characters and the underscore. For non-supported characters,
“NO SUPPORT” is displayed.
If information contains characters other than ID3 tag information,
the audio file may not be played back.
The tag information may not be correctly displayed, depending
on the contents.
Do not make a file’s playback time more than 1 hour.
Playing back MP3/WMA/AAC
MP3/WMA/AAC files are prepared, and then written to USB
memory. Or, synchronize an MP3/WMA file using Windows
Media Player (Ver. 7.1, 8, 9, 9.1, 9.2), and then forward to the
Portable audio player.
A USB memory device can hold up to 10,000 files/1000 folders
(including Root Folders). Playback may not be performed if a
USB memory / Portable audio player device exceeds the
limitations described above.
Do not make a file’s playback time more than 1 hour.
Media supported
This device can play back USB memory / Portable audio player
media.
Corresponding File Systems
This device supports FAT 12/16/32.
Bit rate
This is the “sound” compression rate specified for encoding. The
higher the bit rate, the higher the sound quality, but also the larger
the files.
Sampling rate
This value shows how many times per second the data is sampled
(recorded). For example, music CDs use a sampling rate of 44.1 kHz,
so the sound is sampled (recorded) 44,100 times per second. The
higher the sampling rate, the higher the sound quality, but also the
larger the volume of data.
Encoding
Converting music CDs, WAVE (AIFF) files, and other sound files into
the specified audio compression format.
Tag
Song information such as track titles, artist names, album names,
etc., written into MP3/WMA/AAC files.
Root folder
The root folder is found at the top of the file system. The root folder
contains all folders and files.
CAUTION
Except for private use, duplicating audio data (including MP3/
WMA/AAC data) or distributing, transferring, or copying it,
whether for free or for a fee, without permission of the copyright
holder is strictly prohibited by the Copyright Act and by
international treaty.
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: 32 - 320 kbps
Sampling rates: 48 kHz, 44.1 kHz, 32 kHz, 24 kHz, 22.05 kHz,
16 kHz
Bit rates: 16 - 320 kbps
Sampling rates: 48 kHz, 44.1 kHz
Bit rates: 8 - 576 kbps
Terminology