SBC (Low Complexity Subband Coding) is the mandatory default codec of Classic Bluetooth audio (the A2DP profile), present since 2003 in essentially every wireless speaker and headphone. It was designed to be cheap to implement rather than excellent, and it is merely adequate — acceptable at higher bitrates but clearly behind modern codecs at the rates Bluetooth often negotiates. For years it was the lowest common denominator that any two Bluetooth devices could fall back to, while AAC, aptX, and LDAC competed above it. The arrival of Bluetooth LE Audio and its mandatory LC3 codec, which sounds better at far lower bitrates, is what finally gives the industry a successor to SBC.
