Sony NW-S4 - Manual (Page 22)

22
Glossary
ATRAC3
ATRAC3, which stands for Adaptive Transform Acoustic Coding3, is audio
compression technology that satisfies the demand for high sound quality and high
compression rates.
The ATRAC3 compression rate is approximately 10 times higher than that of the
Audio CD, resulting an increased data capacity for the media.
Bit rate
Indicates the data amount per second. The rate is reflected in bps (bit per second).
In OpenMG Jukebox, the bit rate for recording an audio CD or converting MP3 and
WAV format audio files into ATRAC3 format can be chosen from 132 kbps/105kbps/
66kbps. 105 kbps means 105000 bits of information per second. If the bit rate is large,
that means a large amount of information is used to play music. Comparing music of
the same format, a 105 kbps data offers better sound quality than 66 kbps data, and
132 kbps data offers better sound quality than 105 kbps data. However, audio files in
formats such as MP3 have different encoding methods, and thus sound quality cannot
be determined by simply comparing the bit rate.
Check-in/Check-out
Check-out is to transfer music files from a personal computer to an external device/
media (such as Network Walkman). Returning checked-out music files to the same
computer is to check in. (You cannot move checked-out music files to another
computer.)
You can check-out a music file, check it back in, and then check it out again an infinite
number of times. The SDMI rules provide that up to four copies of a music file can be
checked-out at one time. OpenMG employs a method whereby three copies of a song
can be checked-out simultaneously, while the fourth copy is maintained as a “master“
on your PC. If three copies of the same song are checked-out at a given time, one copy
of the song needs to be checked-in to the computer in order to create an additional
check-out.
MP3
MP3, which stands for MPEG-1 Audio Layer3, a standard for audio files compression
determined by the Motion Picture Experts Group, an ISO (International Organization
for Standardization) working group. It enables compression of audio files to about 1/
10 of the data size of a standard compact disc. Since the MP3 encoding algorithm is
disclosed, there are various encoders/decoders that are compliant with this standard,
including freeware that is available for no charge. Thus, the MP3 standard is widely
used in the computer field.