LC3 (Low Complexity Communication Codec) is anaudio codec specified by theBluetooth Special Interest Group (SIG) for theLE Audio audio protocol introduced about the time ofBluetooth 5.2.[1] It's developed byFraunhofer IIS andEricsson as the successor of theSBC codec.[2] Mono only LC3-SWB is also supported over Bluetooth Classic HFP 1.9, improving on mSBC. It is possible to send 4 LC3 streams to LE audio earbuds, like Samsung's Buds2 Pro.
LC3 provides higher audio quality and betterpacket loss concealment thanSBC,G.722 andOpus, according to subjective testing by the Bluetooth Special Interest Group andETSI.[3][4][5] The conclusion regarding Opus is disputed as the test only included speech audio, but the comparison was made to version 1.1.4 of the reference Opus encoder, using complexity level 0 at 32 kbps and relying onCELT (general audio) instead of the FEC-capableSILK (speech); the test also did not take into account the newer version 1.2 of the Opus encoder released in 2017, where significant improvements were made to low bitrate streams.[5]
LC3plus High Resolution mode is a codec defined byETSI and is not compatible with the LC3 defined byBluetooth SIG.[16]: 3 It's included in the 2019DECT standard.[17]
On November 9, 2022, theJapan Audio Society (JAS) released a statement certifying LC3plus with the"Hi-Res AUDIO WIRELESS" logo.[18] LC3plus is the 4th codec to receive this, alongsideSCL6 (formerly known as MQair),LDAC andLHDC codecs.
The ETSI implementation of LC3plus issource-available software, subject to aETSI Intellectual Property Rights Policy and the usual patent restrictions.[19]
