Digital audio format & file format, Wav (broadcast wav) file format, Mp3 file format – Sound Devices 633 User Manual
Page 40: Mp3 bit rate, Ding, See “digi, Recor der se tup and contr ol
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Track Name Display Style
Right
Digital Audio Format & File Format
Two digital audio formats are available on the 633: Uncompressed PCM (WAV) and compressed
MPEG Layer III (MP3). Uncompressed PCM audio is stored in a WAV file format and compressed
MPEG audio is stored in an MP3 file format. The WAV format is used for projects where audio qual-
ity is critical. The MP3 format is typically used for projects where audio quality is not as critical as
storage space (When recording speech for transcription, for example).
Feature
WAV
MP3
Maximum track count
10
2
Available recording Tracks
L, R, 1, 2, 3, 4, 5, 6, X1, X2
L, R or X1, X2
Allowed sample rates
All
44.1 kHz or 48 kHz
Metadata
Complete metadata support per Broadcast
Wave File (BWF) standard.
Limited metadata support.
Audio data
Uncompressed
Compressed
Storage space used
7.6 MB - 33 MB per track, per minute
Dependant on sample rate
500 KB - 1.2 MB per track, per minute
Dependant on MP3 Bit Rate
WAV (Broadcast WAV) File Format
The 633 writes AES-31 Broadcast Wave formatted files. The audio files created by the 633 include
additional information (Metadata) in the file’s header, bEXT (Broadcast Audio Extension) and iXML
data chunks (
See “Metadata Fields”, page 41
). Software that does not recognize these additional
broadcast wave data chunks will simply ignore them.
MP3 File Format
MPEG Layer III is a lossy compression algorithm, often used for transcription recording purposes.
The 633 records two-channel MP3 audio files with data rates of 320 kb/s, 192 kb/s, or 128 kb/s.
MP3 files do not utilize the any standard container format. No industry-standard tagging format has
defined for the MP3 file format. The 633 utilizes the de facto standard ID3v1 tagging format to store
relevant metadata. (
See “Metadata Fields”, page 41
MP3 Bit Rate
When recording MP3 files, the 633 (and all other MP3 encoders) compresses data to achieve a par-
ticular bit rate. The bit rate refers to how many bits of data per second are encoded into the MP3 file.
A larger bit rate yields a larger file with higher audio quality while a smaller bit rate yields a smaller
file with lower audio quality. To adjust the bit rate of recorded MP3 files, access Setup Menu option
RECORDER > MP3 Bit Rate. The 633 records two-channel MP3 audio files (
) with data rates of 320 kb/s, 192 kb/s, or 128 kb/s.
633 User Guide and Technical Information
34
v. 1.02
Features and specifications are subject to change. Visit www.sounddevices.com for the latest documentation.
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