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How Does The Aptx Codec Improve The Sound Quality Of Bluetooth Devices?

How Does The Aptx Codec Improve The Sound Quality Of Bluetooth Devices?

The Aptx Codec Was Developed To Improve The Sound Of Headphones And Bluetooth Speakers.

If you look at the list of specifications of new Bluetooth headsets and speakers, you will no doubt see the aptX codec name. It is A codec that can improve the sound quality of Bluetooth devices.

The codec is known as the trump card of companies when making Bluetooth equipment. Devices improve wireless voice transmission between sources such as smartphones, tablets, headphones, or speakers.

Bluetooth 5 is a significant change.

Over the past decade, Bluetooth technology has advanced dramatically. Bluetooth 5 focused on improving features for IoT-related applications and improving data transfer speeds to 48 Mbps. In addition, Bluetooth 5.0 can exchange data up to 2 Mbps in a row.

Other essential features of this version include a fourfold increase in range compared to the 4.2 version and a maximum capacity of 200 meters. Dual Audio capability makes it possible to connect two devices simultaneously to a device with Bluetooth 5. The latest version of this technology, released in 2020, is version 5.2.

This article introduced the LE Audio feature and BLE, which can use in hearing aids with low power consumption. Bluetooth version 5.2 can connect a set of audio devices to one or more audio sources using a new codec called LC3.

The introduction of powerful features has made aptX no longer considered as a technology or a unique part for improving sound quality as it used to be. However, it still has advantages that are attractive to know.

Interesting tips on how to transmit audio via Bluetooth

Digital audio is a collection of sound wavelengths at a particular moment in time. Digital sound, unlike a standing wave of sound, is a collection of snapshots of a wave. When many audio wave samples are available, the audio player can convert them into a single sound wave. For example, an audio CD has 44,100 samples per second, each with a value between 0 and 65,535 (or 16 bits).

In other words, we have 44,100 instantaneous wave images per second, with a probability of 65,536 in each. To manage the volume of audio data, compressed audio or MP3 or AAC formats inventing. These codecs eliminate a set of processes for compressing and normalizing the audible sound file using Psychoacoustic Modeling.

This method allows codecs to reduce the amount of audio data. For example, an MP3 file is about one megabyte per minute; its size is ten times smaller than the original file.

Reducing the volume of audio data is associated with reduced quality; That’s why codecs like MP3 are known as lossy codecs. The sound that is removed in the volume reduction process is not recyclable.

Compressed sounds are theoretically of lower quality than normal sounds. Of course, this reduction in rate is not very noticeable and can be detected only in some instances. They improve the performance of compression algorithms, increase bitrate, etc., and improve the quality of compressed audio files.

How does Bluetooth transmit voice data?

Bluetooth is a low-power data transfer technology designed to transfer data between devices at close range. This process consumes less power compared to WiFi and has a lower allowable distance and data transfer rate. With the advancement of Bluetooth technology in recent years, the dimensions of the maximum possible current have increased. Therefore, compared to the early years of the introduction of Bluetooth, it is possible to transfer more data through this technology.

In the early days of Bluetooth, voice data mining uses to transmit data, and the SBC codec reduced sauce volume. The above codec was not developed to maintain maximum sound quality and only reduced processing power because the early devices did not have a powerful battery. SBC has evolved and runs on most devices with a bit rate of 345 kbps in recent years. Overall, the SBC codec has no better quality than MP3 or AAC at best and is almost mediocre. Such problems gave rise to aptX technology.

aptX is designed to overcome problems

The aptX codec was invented to compress audio data, but it uses an almost different compressing data. MP3 uses Psychoacoustic Modeling to reduce the volume of data, while aptX uses a Time Domain ADPCM to minimize the book so that fewer bits are used in each audio sample and the file size is reduced.

Qualcomm currently owns the aptX codec patents. “Audio with the aptX codec has great performance, making it the best sound on Bluetooth devices,” Qualcomm said of the technology. Of course, for the best performance, both smartphones, headphones, or speakers must support the aptX codec. “If the codec is only supported on one device, you will not experience sound quality improvements.”

The aptX HD codec has been slightly improved compared to the original versions. This codec delivers 24-bit audio at 576 kbps. There is another version called aptX Adaptive, which theoretically reduces the sound quality of aptX HD to less bitcoin and the possibility of taking a sample rate of 96 kHz.

The question today is whether the aptX codec still performs as well as it did in the past. The answer may be summed up in words. Today, unlike the early days of Bluetooth development, SBC does not have as many problems with quality reduction.

More precisely, if appropriately implemented, SBC is relatively equal to other lossy codecs.

In contrast, aptX allows Bluetooth audio transmission not to be compromised. Of course, for better quality, just one device support aptX is not enough.

Another essential point to note is the quality and performance of aptX, as you should consider the source and input file of the audio. The aptX HD codec has a good performance in theory, which is compatible with bitcoin and many samples. It is necessary to explain that these capabilities are not visible as long as the input sound and source are not good quality.

Therefore, a better codec helps transmit sound when the original sound is played with better quality. SBC and aptX codecs are not beneficial when the audio and music input files are of poor quality or you use cheap headphones.

In addition to the aptX codec, other examples have been developed to improve voice communication quality via Bluetooth. For example, Sony offers a solution called LDAC for Bluetooth communication, which is only supported on limited devices.

Is aptX leaving the world of Bluetooth?

New versions of aptX are now being used in audio products that perform better than earlier versions. Today, new names such as aptX Low Latency indicate low power consumption and sound quality. When you use Bluetooth headphones, you will notice a mismatch between the sound source and the received sound.

This delay is due to the processing required to deliver audio to your corners via Bluetooth. The low latency codec reduces the standard 200 to 300-millisecond SBC latency to 40 milliseconds to minimize the sound latency experience. Even the aptX Adaptive codec has a slight latency and theoretically has a latency of 80 milliseconds.

In the future, voice communications with Bluetooth will receive important updates, one of which will be in the form of the LC3 Low Complexity Communication Codec. This codec theoretically makes it possible to provide fewer bits while maintaining sound quality.