Codec comparison

You can set the codec of your Vivox voice client during initialization.

The following table compares the four codecs that the Vivox SDK uses.

 OpusSiren 14Siren 7
Network Bitrate*32 kbit/s32 kbit/s32 kbit/s
CPU Usage (Encoding)ModerateLowLower
CPU Usage (Decoding)LowLowLower
Supports configurable bitrate?Yes (6 to 128 kbit/s)NoNo
Audio Sample Rate†48 kHz32 kHz16 kHz
Audio QualityBest (20+ kbit/s)GoodFair

* Numbers listed represent the default bitrate for each codec for one voice stream at theoretical max. Codec bitrates are only in effect while speech is active (either being transmitted or received). These exclude 14.4 kbit/s of overhead from Vivox packet headers while speech is active.

† Higher sample rates allow for higher fidelity audio but do not by themselves guarantee a better sound.