What Is Hi-Res Audio? The Basics

High resolution audio changes your music listening options

Most of us listen to music via streaming on portable devices, such as iPods and smartphones. Although convenient, this trend has taken us backward in what we settle for as a good music listening experience.

File formats used by most streaming services are of low quality. When compared to the CD format, MP3 files and streamed music from iTunes, Spotify, Amazon, (and others) contain less data to make the music.

To fit music into a format that can be easily streamed, and provide the ability to store lots of songs on a portable music player or smartphone, as much as 80 percent of the information in the recording of the original performance may be deleted.

Enter Hi-Res Audio

To counter poor-quality music listening, there is a move to bring back high-quality two-channel audio by extending the capabilities of downloadable and streamable music so that it matches, or surpasses, CD quality. This initiative is referred to as hi-res audio, hi-res music, or HRA. 

Official Hi-Res Audio Logo
Official Hi-Res Audio Logo. Image provided by Sony Europe Press Centre/Creative Commons

What Hi-res Audio Is

The DEG (Digital Entertainment Group, Consumer Technology Association, and The Recording Academy [The Grammy Folks]) define hi-res audio as: "Lossless audio that is capable of reproducing the full range of sound from recordings that have been mastered from better than CD quality music sources."

The term "lossless" means a music file contains all of the information provided in the original studio or live recording process but in digital form. A lossless file is most commonly uncompressed, but there are some compression algorithms that allow the retention of all required information.

The CD format is considered the reference point separating lo-res from hi-res audio. In technical terms, CD audio is an uncompressed digital format that is represented by 16 bit PCM at a 44.1khz sampling rate.

Anything below the CD reference point, such as MP3, AAC, WMA, and other highly-compressed formats are considered 'low-res' audio, and anything above is considered 'hi-res' audio.

Hi-Res Audio Formats

Hi-res audio is represented in physical media by the HDCD, SACD, and DVD-Audio disc formats. However, since physical media is no longer in favor by many, there is a move to provide listeners with the ability to access hi-res audio via downloading and streaming.

Non-physical hi-res digital audio formats include ALAC, AIFF, FLAC, WAV, DSD (the same format used on SACD discs), and PCM (at a higher bit and sampling rate than CD).

What these file formats have in common is that they provide the ability to listen to music in higher quality, but, unfortunately, their files are large, which means that, most often, they need to be downloaded before listening.

Getting Hi-Res Audio Via Downloading

The main way to access hi-res audio content is via download.

This means that most of the time you can't listen to hi-res audio-on-demand. Instead, you download hi-res music files from a content source available on the internet to your PC or other compatible devices.

Two popular hi-res audio music download services are Acoustic Sounds and HDTracks.

Audio Playback Devices

The ability to play hi-res audio files requires an audio product that is compatible with the specific hi-res audio files you wish to play.

You can listen to hi-res audio on your PC, or if you have a network-connected home theater receiver that is hi-res audio compatible, it may be able to access hi-res audio files from network-connected PCs, media servers, or via a flash drive plugged into the receiver's USB port.

Hi-res audio playback is also available through select network audio receivers and portable audio players. Some brands that incorporate hi-res audio playback capability on selected digital audio players, stereo, home theater, and network audio receivers include Astell&Kern, Pono, Denon (HEOS), Marantz, Onkyo, Pioneer, Sony, and Yamaha. Look for the official hi-res audio logo on the product or product packaging (Logo example near the top of this article).

You can also play some hi-res audio content (24bit/96kHz) on non-hi-res audio compatible playback devices using a Chromecast For Audio device, as well as via the DTS Play-Fi system's Critical Listening Mode on compatible Play-Fi devices.

Hi-res Audio Streaming — MQA to the Rescue

Although downloading hi-res audio music files and listening at home through your home network, USB, or copying to a compatible portable player is one option, streaming-on-the-go is more convenient.

With that in mind, a process developed by MQA makes streaming hi-res audio files practical.

MQA stands for Master Quality Authenticated. It provides a compression algorithm allowing hi-res audio files to fit into a much smaller digital space. This allows the music files to be streamed on-demand, instead of going through the less convenient download step.

This makes it easier to stream hi-res audio files on-demand, just as with MP3 and other low-res formats, provided you have an MQA compatible device.

Although MQA files can be streamed, some services may either only provide a download option, or both streaming and download options.

If your device doesn't support MQA, you can still access the audio via download — you just won't get the benefits of MQA encoding.

Some MQA Streaming and Download partners include 7 Digital, Audirvana, Kripton HQM Store, Onkyo Music, and TIDAL.

Qobuz streams hi-res audio in the FLAC format and does not use MQA.

Some MQA Hardware Product Partners include Pioneer, Onkyo, Meridian, NAD, and Technics.

For more details on streaming services and playback products, refer to the MQA Partner Page.

The Bottom Line

After years of listening to inferior audio quality from MP3s, and other compressed audio formats, hi-res audio provides music fans with high-quality listening without being tied to physical media. Both download and streaming options are provided and hi-res audio music is available through several online services.

To take advantage of hi-res audio listening, there are costs involved, both on the hardware and content end. Although hi-res audio capability is incorporated into a growing selection of moderately-priced stereo and home theater receivers, dedicated hi-res audio compatible network audio and portable audio players they can be expensive, and, of course, the price of hi-res audio download and streaming content is higher than their MP3 and lo-res audio file counterparts.

Despite increased audio content and product support, hi-res audio does have its detractors, with an ongoing debate as to its real-world benefits for most listeners.

If you're planning to make the jump to hi-res audio listening, seek out and conduct your own listening tests to see if the price of entry is worth it for you.