Alpine IDA-X303 Ida-x303 Owner's Manual (english) - Page 19

About MP3/WMA/AAC 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. 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 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 WMA Sampling rates: 48 kHz, 44.1 kHz, 32 kHz, 24 kHz, 22.05 kHz, 16 kHz Bit rates: 16 - 320 kbps AAC Sampling rates: 48 kHz, 44.1 kHz Bit rates: 8 - 576 kbps 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. Terminology 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. 17-EN