aptX HD is a Bluetooth codec that can wirelessly transmit Hi-Res Audio files at 24-bit/48kHz and has been engineered to improve the signal-to-noise ratio, resulting in lower background noise. It is used in audio equipment like wireless headphones, speakers, DACs, and AV receivers, quality matters – and the growing interest around Hi-Res Audio proves that the quality of our music sources matter, too.
aptX HD was designed by Qualcomm to answer the growing demand for high resolution audio. This enhanced codec supports 24-bit music quality over Bluetooth. This means listeners can hear even the smallest details in their music. This audio codec ensures your Bluetooth® wireless device can deliver high definition (HD) audio.
aptX HD specs
– Sound quality : THD+N@1kHz: -80dB, SNR@1kHz: 129dB, PEAQ audio quality: -0.05
– Audio Encoding: 24-bit, up to 48kHz sampling rate
– Program memory usage: 3.3kwords (encoder) / 3.6kwords (decoder)
– Data memory usage: 1.8kwords
– Bit Rate : 576 Kbits (48 kHz sampling)
– Capability: Backwards compatible with existing aptX products
Before we can understand AptX HD further, its only fair to get to know more about Hi-Res Audio (HRA). It is basically a lossless audio capable of reproducing the full range of sound from recordings that have been mastered from better-than-CD quality music sources, a sound that closely replicates the quality that the musicians and engineers were working with in the studio at the time of recording.
This means HRA is the core of aptX HD wireless codec. HRA has recently gained popularity, but it isn’t new. It has actually been around for over a decade and has a growing number of dedicated fans willing to fork out a bit more cash for the privilege of listening to Hi-Fi quality tunes both at home and on the go. The difference is that it’s becoming more accessible than ever. HRA tracks are more expensive to buy and most popular digital music vendors don’t even sell Hi-Res Audio tunes (yet).
Hi-Res Audio is an umbrella term for lossless audio, there are a number of file formats that can be used to house a song. Here’s a list of the main ones:
- ALAC (Apple Lossless Audio Codec) and FLAC (Free Lossless Audio Codec)
- APE is a free and very efficient lossless codec from Monkey’s Audio.
- DSD (Direct Stream Digital) The high-resolution codec that originated with SACD (Super Audio CD)
- MQA (Master Quality Authenticated). A new lossless codec of about one-third the size of FLAC.
- WAV is an uncompressed studio-quality file, compatible with different players including iTunes
Benefit of aptX HD
Unlike lossy MP3 files, Hi-Res Audio codecs using apX HD technology are capable of reproducing the full range of sound from recordings that have been mastered from better-than-CD quality music sources, a sound that closely replicates the quality that the musicians and engineers were working with in the studio at the time of recording.
The increased bit depth of Hi-Res Audio improves the dynamic range (or, how loud and quiet a track sounds), basically giving you a greater breadth of things to actually hear from the recording, making tracks sound more expansive and detailed.
Audiophiles swear love Hi-Res streaming services like Tidal, Amazon Music HD, and Qobuz for this reason. It has been rumored that Sony’s WF-1000XM3 will soon get support for aptX HD — something that, until now, they haven’t been able to handle. This will make them appeal to this market by bringing the fidelity of Hi-Res Audio to the convenience of true wireless earbuds, it could reinvigorate its already-brilliant earbuds.
aptX HD support is a feature that only a few true wireless earbuds can claim, including the Cambridge Audio Melomania 1 and the Master & Dynamic MW07. The Apple AirPods, and the newer AirPods Pro certainly don’t come with Hi-Res Audio support. This will make Sony’s earbuds have an edge over Apple’s AirPods Pro. Used in over 1,000 products, you find a full list of devices that support this technology here.
The aptX family
As technology evolves, aptX technology has also evolved with it. It should be noted that aptX HD is only part of a bigger family. Qualcomm is repeatedly push the boundaries, as they innovate around their with premium audio experiences. Apart from aptX HD other members of the family includes;
aptX adaptive
This is Qualcomm’s newest audio codec, designed for the modern mobile user who wants to be free of wires. Ideal for gaming on the go or streaming your latest box-set binge. It combines robust premium audio quality, low-bit rate audio transmission, scalability and the opportunity for low-latency to create the ultimate seamless wireless listening experience, even in the most challenging of radio frequency (RF) environments.
apt X
The original aptX audio technology powers the wireless sound behind many of the world’s finest smartphones, speakers, soundbars, headphones and tablets. Stream music using aptX-enabled Bluetooth wireless devices, so you don’t compromise on sound quality.
aptX low latency
This is used for gaming and provides an experience of ensuring there are no audio delays. It ensures synchronized audio and video content, delivering a premium audio experience for playing the latest game or catching up on TV.
