4 Administrator Settings
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4.4.2 Audio Algorithm The system will automatically select the best audio algorithm based on the call rate and the
capabilities of the remote system. Use this menu to disable audio algorithms in case you want
to remove “low quality” audio, or if you have interoperability issues calling other systems.
G.722 High quality audio (7 kHz at 48kbps, 56kbps or 64kbps)
G.728 Compressed normal quality audio (telephone quality, 3.1 kHz at 16kbps)
G.711 Normal quality audio (telephone quality 3.1kHz at 64kbps). This audio
algorithm is mandatory for video conferencing equipment and is impossible
to uncheck.
G.722.1 Compressed high quality audio (7 kHz at 24kbps and 32kbps).
AAC_LD CD-quality audio, MPEG-4 Advanced Audio Coding Low Delay20 kHz, stereo
at 128kbps20kHz, mono at 64kbps
Call Rate vs Audio algorithms selected
Modify/remove algorithms used by uncheck the different audio algorithms
Automatically preferred audio algorithms on call rates up to and including 192kbps
1. G.722.1 (24kbps or 32kbps)
2. G.728 (16kbps)
3. AAC-LD (56kbps or 64kbps)
4. G.722 (48kbps, 56kbps or 64kbps)
5. G.711 (48kbps, 56kbps or 64kbps)*
6. AAC-LD (48kbps or 128kbps)
Automatically preferred audio algorithms on call rates above 192kbps
1. AAC-LD (128)**
2. AAC-LD (64kbps or 56kbps)
3. G.722 (64kbps, 56kbps or 48kbps
4. G.722.1 (32kbps or 24kbps)
5. G.728 (16kbps)
6. G.711 (64,56,48)*
7. AAC-LD (48)
* AAC-LD, G722 and G711 at 64kbps is used for audio in H323 (IP) calls only
** Dependant that the call rate is above the AAC-LD 128 treshold.