In the current audio market, wireless audio products have won the favour of a large number of users through more freer and easy-to-hand use. Among these wireless audio products, bluetooth technology was used mainly to achieve wireless connectivity and wireless transmission of audio data. The experience of end-users continues to improve and improve as the technology of bluetooth continues to improve。
In the wireless transmission of audio data, because the volume of high-quality audio files is usually large, direct transmission may exceed the carrying capacity of the blue-tooth bandwidth, and the decodors are required to compress and decompress the data to accommodate the blue-tooth transmission requirements. However, this process inevitably leads to some loss of sound quality. Thus, the performance of audio decodors has a decisive impact on the hearing experience of end-users。
As consumers, decodors are one of the important factors we need to consider when selecting wireless audio products. There are many types of coders in the current market, which are based on different technologies, and there are significant differences in usage experiences. In this article, i love the audio network, which will provide you with detailed information about the codecs that are currently in the mainstream of the market and help small partners to make better choices in their procurement。
I. Introduction to bluetooth audio codecing
First, let's get to the workings of wireless audio transmission. In the course of audio wireless transmission, audio files such as mp3 and flac are first restored to pcm format and then converted from bluetooth audio to bluetooth wireless files, sent to the end of the audio device. The audio end reverts the files transmitted by bluetooth wireless to the pcm format, then converts them to simulated signals and zooms them out, through the horn, so that we can hear clear and live voices。
From the working principles of wireless audio transmission, we can see that the bluetooth audio decoding device plays a decisive role in it. Currently in the market, the mainstream audio codecs are sbc, aac, aptx, ldac and lhdc. The main parameters include sampling rate (khz), sampling bits (bit), transmission code rate (kbps) and transmission delay (ms). Together, these parameters determine the performance and sound performance of the bluetooth audio codec。
Sampling rate: refers to the number of times audio signals are sampled per second, usually expressed in khz. Higher sampling rates can better restore audio details
Sample bits: refers to the number of digits per audio sample, usually 16, 24 or 32. Higher bit depth can provide greater dynamic scope and better sound quality
Transfer code rate: the speed at which the decoding device transmits audio data, usually expressed as kbps per kbit. The higher the bit rate, the better the audio quality usually
Transfer time delay: the time required to transfer the instructional audio signal from the source to the receiving device is usually expressed in ms. Lower time lags can lead to better experiences of games, videos and video calls。
Sbc codec
Sbc (subband codec) is an audio coding technique developed by sig, bluetooth technology development organization, for the a2dp (advanced audio distribution profile) audio profile. Sbc supports 16bit/44khz audio with a maximum code size of 328kbps。
Aac codec
The aac (advanced auto coding) codecing is a damaging audio compression format defined by the mpeg-4 standard, developed jointly by fraunhofer iis, duby laboratory, at&t and sony. Aac can support 16bit/44khz audio with a maximum code rate of 576 kbps。
Aptx codec
The aptx codec is an audio coding technique developed by qualcomm highcom. Based on different application scenarios, several versions are derived, including aptx, aptx adaptive, aptx hd, aptx losles, aptx low latency (ll), etc., up to 24bit/96khz with a maximum code rate of 1mbps。
Ldac codec
The ldac codec is a high-resolution audio coding technique developed by sony sony to transmit high-quality audio through bluetooth. Ldac can support up to 24bit/96khz with a maximum code rate of 990 kbps。
Ldac was the first codec decoder to be certified by hi-res auto wireless, issued by jas, japan audio society, to print “small gold” labels on products and serve as a positive guide when consumers purchase products。
Lhdc codec
Lhdc, full name low-latency hi-definiation audio code (low delay and high-resolution audio decodifier), is a high-sound bluetooth compiler based on the a2dp bluetooth agreement and developed by a very sophisticated technology. Lhdc can support up to 24bit/192khz audio with a maximum code rate of 1 mbps. At the same time, using the lhcc transmission protocol, the lhdc team will provide a full set of process services for obtaining hi-res audio wireless certification, including testing templates and providing reliable corrective advice to assist clients in obtaining hi-res audio wireless certification。
The five decoders detailed above require dual-end support for both audio source equipment and audio products. Among them, sbc is the coded format mandatory under the bluetooth a2dp agreement, with all bluetooth devices being tacitly supported; aac is the basis for comparison and has a wider application; the remaining three can support 24bit/96khz audio and provide higher sound decodifiers, aptx is supported only by high-level home-owned terminal chips, ldac and lhdc are free of platform restrictions and can be used through official authorization。
In recent years, with the rise of many upstream bluetooth soc manufacturers and rising consumer demand for high quality, the lhdc audio decoding device has gained a wide range of applications in the market, with its significant advantage in technical specifications, low delays and multiplatform compatibility, and has become an important force in promoting high quality audio penetration。
Ii. Introduction to lhdc high-resolution audio decoder
The lhdc audio decoding device, developed by savitech corp., has extensive experience in simulation, hybrid signal and integrated circuit design, providing high-quality audio from all electronic devices, from the hi-fi audio system to mobile phones, as well as individualized solutions for each audio application。
Lddc audio decodor development background:
Savitech corp. Is a company created by a group of hifi fever friends because the sbc, aac-traditional bluetooth agreement does not meet the demands of the hi-fi sound, and other agreements do not have low delays and are poorly designed or are platform-limited. As a result, the lhdc protocol was launched in a very advanced manner, taking into account the needs of all users in all directions, with the aim of providing a whole new high-sound, fast and low-delayed audio experience for video viewing, live playing, listening to music, games, etc。
Lhdc audio decoding device advantage:
For the sound source device end. Lhdc, as the leading bluetooth decoding technology, is increasingly supported by audio products as it develops in the future. As a result, sound-based equipment supports lhdc, which improves product functionality and adapts to peripheral audio products, thereby enhancing product market competitiveness and user experience。
For audio product end. As one of the core functions of the audio product, the audio decodifier supports the ability of lhdc to provide users with data transmissions that exceed the sbc three times the sbc, leading to higher quality wireless audio. At a time when sound is increasingly important, product competitiveness can be greatly enhanced. At the same time, the certification of hi-res audio wireless allows consumers to be better informed about product performance。
For end users. Consumers select products that support lhdc audio decoding devices, which means being able to experience the fine, high-resort quality of the 24bit/192khz wireless audio transmission, and feel more sincerely the emotions that music creators want to convey。
Of course, the performance of sound is a complex system engineering exercise, and while audio decodors play a key role, consumers also need to take into account other important factors such as hardware configuration, tone and branding when selecting products. In addition, the music experience itself is highly subjective, and different growth contexts, times and emotional states affect individual feelings for music, so the first element of the selected product is still considered “i like it”。
Iii. I love audionet summaries
In the current market for bluetooth audio, as a result of product positioning and ecological differences, a variety of bluetooth audio decodors have emerged in the market, requiring consumer choices. Through this article, many small partners are believed to have a general understanding of the bluetooth audio decodator and its decisive role in the bluetooth audio product, so that the selected product is not lost。
Lhdc, as one of the leading technologies in the bluetooth audio codecer, is able to effectively improve the market competitiveness of branded products with high-quality audio experience and multiplatform support for more liberal and flexible use. As a result, lhdc-supported products are expanding rapidly, acquiring a large number of end phone brands and the introduction of headphone audio brands. I love the fact that i'm going to use lhd for sharing all the products。
