L2HC

L2HC (Low Latency Low Complexity High Resolution Audio Codec) is a proprietary audio codec technology developed by Huawei. L2HC allows high-resolution audio streaming over Bluetooth and NearLink with lossless data compression of digital music. It is a high-quality Bluetooth based on the A2DP Bluetooth protocol and NearLink based on its native L2HC 3.0+ StarLink protocol with Polar protocol by Huawei and allows a bit-rate of up to 1.5Mbps compared to SBC's bit rate of 345kbps and LDAC's bitrate of 960kbps.

L2HC is an alternative to Bluetooth SIG's SBC and LC3 codecs. Its main competitors are Savitech's LHDC, Qualcomm's aptX-HD/aptX Adaptive and Sony's LDAC codec.

Starting from AOSP-based EMUI 11 in 2020, L2HC audio codec has been part of Huawei products, especially audio products from Huawei FreeBuds line. Compared with Sony's LDAC, Huawei's L2HC provides more flexible bitrate space, and can adapt to a lower bitrate in the face of interference and other scenarios, so as to better balance sound quality and lag. Currently, some Huawei models support L2HC when upgraded to EMUI 11 or HarmonyOS 2.0 or later alongside OpenHarmony and Oniro OS. In September 2023, the audio codec was updated, L2HC 3.0 which increased the high transmission bit rate, with peak bit rate up to 1920kbit/s with 1.5Mbit/s of Bluetooth transmission that is compared to CD audio quality.