Yealink SIP-T3 Administrator's Manual page 198

Codec
G729AB(G729B)
G726(16 kbps)
G726(24 kbps)
G726(32 kbps)
G726(40 kbps)
G723(53 kbps)/ G723(63 kbps)
iLBC(15.2kbps)
iLBC(13.33kbps)
opus
Note
: The network bandwidth necessary to send the encoded audio is typically 5~10% higher than the bit rate due to pack-
etization overhead. For example, a two-way G.722 audio call at 64 Kbps consumes about 135 Kbps of network bandwidth.
The Opus codec supports various audio bandwidths, defined as follows:
Abbreviation
NB (narrowband)
MB (medium-band)
WB (wideband)
SWB (super-wideband)
FB (fullband)
Note
: The T40P/T40G/T23P/T23G/T21(P) E2/T19(P) E2 phones support using WB for Opus encoding, and using NB, MB,
WB, SWB and FB for Opus decoding.
The T57W/T54W/T53W/T53/T53C/T48U/T48S/T46U/T46S/T43U/T42U/T42S/T41S/T27G phones support using WB
(default) or NB for Opus encoding, and using NB, MB, WB, SWB and FB for Opus decoding.
The CP920/CP925/CP935W phones support using anyone from NB to WB for opus encoding, and using NB, MB,
WB, SWB and FB for opus decoding.
The phones support up to two calls or a three-way conference when using Opus.
The following table lists the audio codecs supported by each phone model:
Algorithm Reference
G729AB RFC 3551
G.726 RFC 3551
G.726 RFC 3551
G.726 RFC 3551
G.726 RFC 3551
G.723.1 RFC 3551
iLBC RFC 3952
iLBC RFC 3952
opus RFC 6716
Audio Bandwidth
4 kHz
6 kHz
8 kHz
12 kHz
20 kHz
Bit Rate Sample Rate
8 Kbps 8 Ksps
16 Kbps 8 Ksps
24 Kbps 8 Ksps
32 Kbps 8 Ksps
40 Kbps 8 Ksps
5.3 Kbps
8 Ksps
6.3 Kbps
15.2 Kbps 8 Ksps
13.33 Kbps 8 Ksps
8-12 Kbps 8 Ksps
16-20 Kbps 12 Ksps
28-40 Kbps 16 Ksps
48-64 Kbps 24 Ksps
64-128 Kbps 48 Ksps
Sample Rate (Effective)
8 kHz
12 kHz
16 kHz
24 kHz
48 kHz
Audio Features
Packetization Time
20ms
20ms
20ms
20ms
20ms
30ms
20ms
30ms
20ms
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