What’s the difference between APTX and APTX HD WIRELESS AUDIO

On Bluetooth headset devices, users often come across two sound parameters that are quite similar but have different performances, namely aptX and aptX HD.

aptX is a Bluetooth audio encoder that can deliver 16-bit/44.1kHz CD-equivalent audio. In addition, this audio standard will usually be compressed at a ratio of 4:1 with a transmission rate of 352kbps.

aptX is almost an important factor for users to be able to hear high-quality sound through wireless headphones. How aptX works can be understood as follows: the sound from the transmitter (smartphone, laptop…) will be compressed in encrypted form and, when transmitted, decompressed by the receiver on the headset output to analog audio it to the user’s ear.

The process of compressing and decompressing the above audio will more or less experience a delay between the emitted sound source and the actual sound that the user hears. Normally, if you listen to music, the audio delay is almost insignificant. However, if you switch to watching the video, the delay will cause the dialogue not to match the actor’s facial gestures, more or less causing discomfort.

Compared to other audio encoders, aptX has been designed to limit audio delay during use. In addition, another variant, aptX LL (Low Latency), can reduce audio latency down to 0.032 seconds – fast enough for the human brain to not distinguish the delay. Since then, aptX LL is often applied to specialized gaming headsets for games that require the highest accuracy in sound, typically shooters.

Meanwhile, Aptx HD is a new generation audio encoder that can transmit audio with quality up to 24-bit/48kHz, and audio compression-only stops at 4:1 with 576kpbs quality. If only for basic understanding, Aptx HD will give better sound quality than standard aptX, equivalent to what wired headphones can do.

A little more intensive, 24-bit/48KHz audio will have higher quality, listeners will get more detail in each song. However, 24-bit/48 kHz music coming from a wired headset and a wireless headset that supports aptX HD will still have a certain difference in quality, mainly coming from sound compression. Although aptX HD has a very low sound compression level of 4:1, this will more or less make the sound to the user’s ears more opaque and noisy when felt through wired headphones; this difference is difficult to perceive by popular music users.

Next, AptX HD outperforms traditional AptX in audio transmission quality (576kbps versus 352kpbs). The unit “kpbs” can be understood similar to how we measure Internet speed: the larger this number is, the more proportional the transmission bandwidth will be, from which the audio will be less compressed, bringing quality better as well as reduced latency.

Most devices integrated with aptx HD are mostly professional audio devices, such as home audio systems, or professional portable music devices such as Fiio X5, Ibasso music players. DX200, AK380…

Not only need a source, but users also need a high-quality headset and speakers that support the aptX HD standard to optimize their music experience. Usually, big sound companies like Sony, Audio Technica will integrate aptX HD on their wireless headphones. For more accurate information, you can read the headset specifications on its website or print them on the product box.