Low Latency High-Definition Audio Codec (LHDC) is an audio codec technology developed by Savitech. LHDC allows

high-resolution audio High-resolution audio is a term for music files with bit depth greater than 16-bit and sampling frequency higher than 44.1 kHz or 48 kHz used in CD and DVD formats. The Audio Engineering Society (AES), Consumer Technology Association ( ...

streaming over

Bluetooth Bluetooth is a short-range wireless technology standard that is used for exchanging data between fixed and mobile devices over short distances and building personal area networks (PANs). In the most widely used mode, transmission power is li ...

. It is a high-quality Bluetooth codec based on the A2DP Bluetooth protocol and allows a bit-rate of up to 1000 kbps compared to SBC's bit rate of 345 kbps. LHDC is an alternative to Bluetooth SIG's SBC and LC3 codecs. Its main competitors are Qualcomm's aptX-HD/ aptX Adaptive, Huawei 's L2HC and Sony's LDAC codec. Starting from Android 10, enumeration constant symbols for LHDC and LLAC are part of the Android Open Source Project, enabling every OEM to integrate this standard into their own Android devices freely. Older versions of Android require LHDC/LLAC enumeration constant symbols to be implemented by the smartphone manufacturers or Android app. Android apps with this type of LHDC support include Savitech's Hi-Res BT Player, FiiO Music, HIFIMAN Music and DA&T Audio.

LHDC

LHDC supports bitrates of 160kbps~1000kbps, bit-depth of up to 24 bit and

sample rate In signal processing, sampling is the reduction of a continuous-time signal to a discrete-time signal. A common example is the conversion of a sound wave to a sequence of "samples". A sample is a value of the signal at a point in time and/or ...

of up to 192 kHz. The first

Smartphone A smartphone is a mobile phone with advanced computing capabilities. It typically has a touchscreen interface, allowing users to access a wide range of applications and services, such as web browsing, email, and social media, as well as multi ...

to support LHDC was the Huawei Mate 10. On 17 September 2019, the Japan Audio Society (JAS) certified LHDC with their Hi-Res Audio Wireless certification. As of June 2024, the codecs certified by the JAS to bear the Hi-Res Audio Wireless logo are LHDC, LDAC, SCL6, LC3plus, SHDC, and aptX Adaptive.

LLAC

Low Latency Audio Codec (LLAC) is also called LHDC LL. It is based on the high definition wireless audio technology from LHDC, but designed for low latency and features an auto-detect gaming mode. Savitech claims LLAC has end-to-end latency of around ~30ms. LLAC supports bitrates of 400/600 kbit/s, bit-depth of up to 24 bit and

of up to 48 kHz. LLAC has no hardware requirement for the transmitter. The first

to support LLAC was the Huawei P30.

Hi-Res Wireless Audio (HWA) Union

On 2 September 2018 the Hi-Res Wireless Audio (HWA) Union was formed to promote LHDC adoption. Also known as the HWA Alliance. The HWA Union Board of Directors includes: * AKM * China Electronics Technology Group Corporation * Cirrus Logic * Edifier * Guoguang Electric * HiFiMAN * HiVi *

Huawei Huawei Technologies Co., Ltd. ("Huawei" sometimes stylized as "HUAWEI"; ; zh, c=华为, p= ) is a Chinese multinational corporationtechnology company in Longgang, Shenzhen, Longgang, Shenzhen, Guangdong. Its main product lines include teleco ...

* Institute of Acoustics of the Chinese Academy of Sciences * Savitech * iriver * Sennheiser * Taihe Music Group Other HWA Union members include: * ams AG * Astell & Kern * Audio-Technica * Aukey * Cayin * Cozoy * Coolhere * Colorfly * DA&T * DA-ART * DUNU * FiiO * Fostex * Haylou * HiBy * infly * iEAST * Liesheng * Musiland * NFJ FX-AUDIO * OC Studio * Onkyo * Pioneer * ProStereo * QCY * Questyle Audio * Quloos (QLS HiFi) * Radius * Shanling * S.M.S.L * TASCAM *

TEAC () is a Japanese electronics manufacturer. TEAC was created by the merger of the Tokyo Television Acoustic Company, founded in 1953, and the Tokyo Electro-Acoustic Company, founded in 1956. Overview TEAC has four divisions: *TASCAM - con ...

* TempoTec * Tecsun * TiinLab * Topping * Tube Fan Audio * VMN * xDuoo * YULONG Audio * 1MORE

HWA Certification

On March 27, 2018, Huawei and Savitech announced the Hi-Res Wireless Audio (HWA) Certification. Platinum HWA Certification requires frequency response over 40 kHz, THD+N<-90 dB, SNR>110 dB, and playback of at least 24bit/96 kHz. Gold HWA Certification requires frequency response over 20 kHz, THD+N<-80 dB, SNR>100 dB, and playback using the at least 24bit/48 kHz.

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