Low Latency High-Definition Audio Codec (LHDC) is an

audio codec An audio codec is a device or computer program capable of encoding or decoding a digital data stream (a codec) that encodes or decodes audio. In software, an audio codec is a computer program implementing an algorithm that compresses and decompres ...

technology developed by Savitech. LHDC allows

high-resolution audio High-resolution audio (high-definition audio or HD audio) is a term for audio files with greater than 44.1 kHz sample rate or higher than 16-bit audio bit depth. It commonly refers to 96 or 192 kHz sample rates. However, there also ex ...

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 limi ...

. it is a high-quality Bluetooth codec based on the A2DP Bluetooth protocol and allows a bit-rate of up to 900 kbps compared to SBC's bit rate of 345 kbps. LHDC is an alternative to

Bluetooth SIG The Bluetooth Special Interest Group (Bluetooth SIG) is the standards organization that oversees the development of Bluetooth standards and the licensing of the Bluetooth technologies and trademarks to manufacturers. The SIG is a not-for-profit ...

's SBC and LC3 codecs. Its main competitors are Qualcomm's aptX-HD/

aptX Adaptive aptX (''apt'' stands for ''audio processing technology'') is a family of proprietary audio codec compression algorithms owned by Qualcomm, with a heavy emphasis on wireless audio applications. History The original aptX algorithm was developed ...

and Sony's LDAC codec. Starting from

Android 10 Android 10 ( codenamed Android Q during development) is the tenth major release and the 17th version of the Android mobile operating system. It was first released as a developer preview on March 13, 2019, and was released publicly on Septembe ...

, enumeration constant symbols for LHDC and LLAC are part of the

Android Open Source Project Android is a mobile operating system based on a modified version of the Linux kernel and other open-source software, designed primarily for touchscreen mobile devices such as smartphones and tablets. Android is developed by a consortium of ...

, 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 400/560/900 kbit/s, 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 sp ...

of up to 96 kHz. The first

Smartphone A smartphone is a portable computer device that combines mobile telephone and computing functions into one unit. They are distinguished from feature phones by their stronger hardware capabilities and extensive mobile operating systems, whic ...

to support LHDC was the

Huawei Mate 10 The Huawei Mate 10, Huawei Mate 10 Pro and Huawei Mate 10 Lite are Android smartphones designed and marketed by Huawei as part of the Huawei Mate series. There is also a Mate 10 Porsche design, which has 256Gb of storage but is otherwise identic ...

. On 17 September 2019, the Japan Audio Society (JAS) certified LHDC with their Hi-Res Audio Wireless certification. Currently the only codecs with the Hi-Res Audio Wireless certification are LHDC and LDAC.

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 Huawei P30 is a line of Android-based smartphones manufactured by Huawei. Unveiled on 26 March 2019, they succeed the Huawei P20 in the company's P series line. Specifications Hardware Their designs are similar to those of the P20. The P30 P ...

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 The AKM () is an assault rifle designed by Soviet small arms designer Mikhail Kalashnikov in 1959. It is the most ubiquitous rifle of the Kalashnikov rifles. It was developed as a replacement to the AK-47 introduced a decade prior. Introduc ...

* China Electronics Technology Group Corporation *

Cirrus Logic Cirrus Logic Inc. is an American fabless semiconductor supplier that specializes in analog, mixed-signal, and audio DSP integrated circuits (ICs). Since 1998, the company's headquarters have been in Austin, Texas. The company's audio processo ...

* Edifier * Guoguang Electric *

HiFiMAN HiFiMAN Electronics is a Chinese manufacturer of audio products including headphones, amplifiers, and portable audio players. Hifiman is known for its high-end audio products, initially made under the brand Head-Direct but now only as HIFIMAN. ...

* HiVi *

Huawei Huawei Technologies Co., Ltd. ( ; ) is a Chinese multinational technology corporation headquartered in Shenzhen, Guangdong, China. It designs, develops, produces and sells telecommunications equipment, consumer electronics and various smar ...

* Institute of Acoustics of the Chinese Academy of Sciences * Savitech * iriver *

Sennheiser Sennheiser electronic GmbH & Co. KG (, ) is a German privately held audio company specializing in the design and production of a wide range of high fidelity products, including microphones, headphones, telephone accessories and aviation headse ...

* Taihe Music Group Other HWA Union members include: *

ams AG ams-OSRAM AG, formerly known as austriamicrosystems AG (originated from Austria Mikro Systeme) and ams AG (before acquiring Osram), is an Austrian electronics company that designs and manufactures sensors for small form factor, low power, high ...

Astell & Kern Astell & Kern is a South Korean consumer electronics company founded in October 2013, and is wholly owned by Dreamus. The company manufactures media players, CD players, headphones, and home cinema products. It was launched as a premium success ...

Audio-Technica (stylized as audio-technica) is a Japanese company that designs and manufactures professional microphones, headphones, turntables, phonographic magnetic cartridges, and other audio equipment. Company history Audio-Technica was established ...

* Aukey * Cayin * Cozoy * Coolhere * Colorfly * DA&T * DA-ART * DUNU * FiiO * Fostex * Haylou * HiBy * infly * iEAST * Liesheng * Musiland * NFJ FX-AUDIO * OC Studio *

Onkyo is a Japanese consumer electronics company, specializing in premium home cinema and audio equipment, including AV receivers, surround sound speakers and portable devices. The word ''Onkyo'' translates as "sound resonance". ''On'' () is from ...

Pioneer Pioneer commonly refers to a settler who migrates to previously uninhabited or sparsely inhabited land. In the United States pioneer commonly refers to an American pioneer, a person in American history who migrated west to join in settling and de ...

* ProStereo * QCY * Questyle Audio * Quloos (QLS HiFi) * Radius * Shanling * S.M.S.L * TASCAM *

TEAC TEAC may refer to: * TEAC Corporation () 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 ...

* TempTec *

Tecsun Tecsun Co., Ltd. () is a Chinese company founded in 1994 and headquartered in Dongguan, Guangdong. It designs and manufactures radios, from simple handheld AM/ FM receivers to more sophisticated digital units with shortwave, longwave, airband, ...

* 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 using the 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.

References

External links