Video/Voice/Speech Codecs

Which codec component should I use for my Grandstream phone?

PCMU (G711u) is used by default. Both PCMU and PCMA provide toll-quality, but they also have the highest bandwidth consumption. If you have limited network bandwidth, you can opt for a lower bit-rate codec like G723 or G729, which provide near toll-quality sound with much lower bandwidth consumption. If bandwidth is not a concern, try using PCMU, PCMA, or even the wideband codec G722, which offers high-quality audio.

For instance, if you have a basic high-speed connection at home (768kbps/128kbps), configure your phone with G723 or G729 to provide the best available audio quality. If you have T1 bandwidth capacity, configure your phone with G711 (a/μ) or G722 for toll-free or high-quality audio experience.

Which audio codecs do Grandstream products support?

All phones support similar codecs, and they are listed below. Note that BT100 doesn’t support GSM, and GXV doesn’t support G722. Each codec has its uniqueness for specific applications.

HT Series – PCMU (G711u), PCMA (G711a), G729A/B, G723.1, G726-32, iLBC HT502 – PCMU (G711u), PCMA (G711a), G729A/B/E, G723.1, G726-40/24/16, iLBC BT Series – PCMU (G711u), PCMA (G711a), G729A/B, G723.1, G722, G726-32, iLBC BT200 – PCMU (G711u), PCMA (G711a), G729A/B, G723.1, and GSM codecs GXP Series – PCMU (G711u), PCMA (G711a), G729A/B, G723.1, G722, iLBC GXV3000 – PCMU (G711u), PCMA (G711a), G729A/B, G723.1, GSM GXP2200 – PCMU (G711u), PCMA (G722a), G729A/B, G722