General Use
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5.4.2 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 meeting equipment and is impossible to uncheck.
G.722.1 Compressed high quality audio (7 kHz at 24kbps, 32kbps and 48kbps).
AAC-
LD CD-quality audio, MPEG-4 Advanced Audio Coding Low Delay (20 kHz, stereo at
128kbps, 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 (64kbps or 56kbps)
4. G.722 (56kbps, 64kbps or 48kbps)*
5. G.711 (64kbps, 56kbps or 48kbps)**
6. AAC-LD (48kbps or 128kbps)
Automatically preferred audio algorithms on call rates above 192kbps
1. AAC-LD (128kbps)***
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 (64kbps, 56kbps, 48kbps)**
7. AAC-LD (48kbps or 128kbps)
* G.722 at 64kbps is used in H.323 (IP) calls only.
** G.711 at 64kbps is used in SIP and H.323 (IP) calls only.
*** Dependent on a call rate above the AAC-LD 128 threshold. Note that this is not available on all TANDBERG systems.