ZyXEL Communications DMA-1000 Series, User Manual

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Chapter 9 Configuring the DMA
DMA-1000 Series User’s Guide
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9.10.1 Audio Formats
This section provides background information on audio formats mentioned in the previous
section.
9.10.1.1 S/PDIF
S/PDIF (Sony/Philips Digital Interface Format) is also IEC 958 type II, part of IEC-60958. S/
PDIF is a collection of low-level protocol and hardware specifications for carrying digital
audio signals between devices and stereo equipment.
9.10.1.2 AAC
AAC (Advanced Audio Coding) is a standardized digital audio compression method. Sony,
AT&T, Dolby, Nokia, Fraunhofer (FhG) and other companies cooperated to develop AAC to
provide improved performance compared to MP3 (MPEG-1 Audio Layer 3). Various products
including Apple’s iTunes and iPod, the Sony PlayStation 3 and many cell phones support
AAC playback. AAC has been promoted as the successor to MP3 although at the time of
writing, MP3 still remains popular. AAC is also known as MPEG-4 AAC because it is
included in the Moving Pictures Experts Group (MPEG) MPEG-4 standard.
9.10.1.3 Dolby Digital
Dolby Digital is one of several audio compression technologies (codecs) produced by Dolby
Laboratories.
Dolby Digital (also called AC-3) is the most common version. It contains up to six discrete
channels of sound. Five channels for normal-range speakers (right front, center, left front,
right rear and left rear) and one channel for the subwoofer. This is often abbreviated as 5.1.
The Dolby Digital format also supports mono and stereo usage.
Dolby Digital is also known as DD, DD 5.1, Dolby Surround AC-3 Digital, Dolby Stereo
Digital, Dolby SR-Digital, SR-D, Adaptive Transform Coder 3, AC-3, Audio Codec 3,
Advanced Codec 3, Acoustic Coder 3, ATSC A/52, and ATSC A/52 Rev. B.
9.10.1.4 WMA
WMA (Windows Media Audio) is Microsoft’s proprietary audio compression format.
Although WMA has not been nearly as popular as MP3, WMA Pro is part of Microsoft's
Windows Media framework and is positioned as a competitor to AAC. Many consumer
devices and media players support the playback of WMA files.
9.10.1.5 LPCM
LPCM (Linear Pulse Code Modulation is a method for digitally encoding audio information.
In LPCM an audio waveform is represented by a sequence of amplitude values recorded at a
sequence of times. LPCM most commonly supports two audio channels (stereo).
9.11 Language Settings
Use this menu to select the language that the DMA menus use.
Select OPTION > Language Settings to open the following menu.