LDAC is a wireless audio coding technology developed by Sony. It was first unveiled at the 2015 CES Consumer Electronics Show. At the time, Sony said that LDAC technology was three times more efficient than the standard Bluetooth encoding and compression system. In this way, those high-resolution audio files will not be over-compressed when wirelessly transmitted, which will greatly degrade the sound quality. When transmitting LPCM high-resolution audio, LDAC technology maintains its maximum bit depth and frequency response range, enabling high-quality transmission even at 96kHz/24bit audio. In contrast, the traditional Bluetooth audio transmission technology, before transmitting LPCM audio, the first thing to do is to "degrade" the high-resolution video to a CD quality of 44.1 kHz/16 bit, and then transmit it through 328 kbps, which is equivalent to Two large amounts of information loss, the final quality is far from the quality of the CD. LDAC provides three transmission modes, the first is the quality-first 990kbps mode, followed by the default 660 kbps normal mode, and finally the 330kbps mode similar to the normal Bluetooth standard, mainly to ensure the quality of the connection. In the screenshot of the Android O Developer Preview, we can see that LDAC also provides these three transmission modes in the system. aptX is an audio codec standard. The standard is integrated with the Bluetooth A2DP stereo audio transmission protocol. The traditional Bluetooth stereo audio coding standard is: SBC, commonly known as narrowband coding, and aptX is a new coding standard introduced by CSR. Under the condition of SBC encoding, the Bluetooth stereo audio transmission delay time is above 120ms, and with the aptX encoding standard, the Bluetooth stereo audio transmission delay time is 40ms. The delay that most people can feel is a small number of 70ms. Therefore, if the aptX standard is adopted, the user will not feel the delay in actual use, just like the experience of watching TV directly with bare ears. SBC is a public protocol. The devices of various manufacturers can be compatible with each other. aptX is a proprietary protocol of CSR. Therefore, devices such as TVs and headphones/speakers need to adopt CSR software technology or chip technology. The party can only support it. The emergence of aptX HD is related to the popularity of HD audio, which can support up to 24-bit/48kHz audio, which means we can hear better sound music on wireless devices. Compared to the traditional aptX 352kbps ratio, aptX HD has an advantage over the 576kbps bit rate. apt-X is currently divided into three categories, normal apt-X, apt-X HD and apt-X Low Latency. According to Sony's official definition, LDAC is a coding technology that can transmit high-resolution audio wirelessly, allowing users to transmit high-quality audio at an amazing 990kbps rate by wireless means. Unlike traditional Bluetooth encoding technologies such as SBC, LDAC does not undergo any degradation when transmitting high-resolution audio content, and allows the device to transmit more data wirelessly for better sound quality. Sony said this is mainly because of "more efficient coding and optimized information packaging." Sony LDAC is a high-quality audio codec based on Bluetooth connection. According to official data, it supports a high sampling rate of 24 bits, supports 990 kbps of data, and provides 24-bit/96 kHz compression-encoded data transmission and decoding [FLAC 24bit] The typical compression coding rate of /96kHz is around 2350kbps]. Sony's Walkman and other devices also measure the typical application of LDAC [such as battery life] by transmitting 24bit/96kHz FLAC. This standard is clearly much higher than apt-X, AAC, and probably much higher than apt-X HD [may only support up to 48kHz]. Of course, LDAC also needs to support LDAC both on the transmitter and receiver. apt-X is a special coding standard in Bluetooth. It was originally a CSR company. As CSR was acquired by Qualcomm, apt-X certification became more commercialized. The company's official website also failed to find many technologies. data. apt-X is currently divided into three categories, normal apt-X, apt-X HD and apt-X Low Latency. Prior to Qualcomm's acquisition of CSR, apt-X Lossless had demonstrated technical data superior to FLAC compression ratio, and now it seems to be no longer mentioned, and the apt-X HD specification has become a 24-bit high sampling rate and LPCM transmission technology. The point is that there are not many devices that support apt-X HD authentication. To enjoy aptX HD, you must have the corresponding hardware, the so-called CSR8675 Bluetooth audio system-on-chip. It not only supports hard drives with higher bitrates, but also provides better digital signal processing. On the other hand, this also means that aptX HD cannot be obtained by software upgrade, you have to buy new hardware. However, aptX HD is backward compatible. If you use a headset that does not support HD, the transfer will automatically switch to normal aptX. Agriculture Staple,604 Fixing Nail,Hardware Staples Nail,Custom Agricultural Use Nail Zhejiang Best Nail Industrial Co., Ltd. , https://www.beststaple.com
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