- HD audio, or high-definition audio, enables streaming music to sound more like an original studio recording.
- While the specifications for HD audio can vary, the term is generally used to refer to digital music formats that offer at least CD-quality mastering.
- Amazon Music, Tidal, and Qobuz all offer HD audio options via streaming.
- To truly take advantage of the added benefits of HD audio, you'll need gear that can support the higher quality sound.
If you're ready to be fully immersed in music from your favorite artists, you're likely a good candidate to explore HD audio and what it can offer your ears. Though once a concept geared mostly toward big audiophiles, HD music streaming solutions are now expanding to the mainstream.
On that note, Amazon Music is one of the latest services to offer higher quality audio options, so you may have seen an advertisement for HD Music and wondered what it's all about. In short, HD music is about allowing you to listen to music exactly as the recording artist intended, with quality that comes closer to the studio recording itself.
If you're someone who already has a pair of good speakers or headphones, then you'll likely want the highest quality music to flow through your gear. Thankfully, there are several streaming services that now offer HD music plans for a premium subscription price. It's very similar to having a high-end TV and needing to pay for Netflix's Ultra HD plan in order to make sure you can take advantage of your display's 4K resolution.
While listening to higher quality music seems like an obvious choice, there are still a few drawbacks or hurdles related to HD music. Below, we've broken down some of the basics about HD audio to help you determine how to get started or whether it's right for you.
What is HD audio?
HD audio is a general term used to refer to digital audio tracks that are presented in at least CD-quality. Unlike typical streaming music tracks (like those on Spotify), HD audio tracks use lossless compression so more information from the original recording is preserved. Examples of common HD music formats include FLAC and WAV, while examples of common lossy music formats include MP3 and AAC.
When music streaming first became widely available, services initially relied on lossy music formats in order to reduce the file size of songs so streaming wouldn't use too much bandwidth. This is fine for casual listening, but this kind of compression leads to a loss of detail, dynamic range, and overall quality, especially if you're listening to music on a high-end system.
Home internet connections have since improved, however, and good audio gear has come down in price. With that in mind, more platforms are starting to embrace lossless HD music tracks with larger file sizes in order to provide listeners with a higher quality experience.
In order to be considered HD, music tracks typically require lossless compression and a minimum sample rate of 44.1kHz, a minimum bit depth of 16-bits, and a minimum bitrate of 850kbps. With that said, there is no formal standard for HD audio, so exact specifications can vary. Labels like hi-res, high-resolution, and Ultra HD are also commonly used to refer to music tracks that actually exceed CD-quality, with sample rates and bit depths even higher than 44.1kHz and 16-bit.
But just what do these sample rate and bit depth specifications really mean? Well, they relate to how the track was mastered digitally during the recording process. For instance, when an HD music track has a sample rate of 44.1kHz, that means that the original audio signal was digitally converted, or sampled, 44,100 times per second. Meanwhile, the bit depth refers to the size of the information in each of those samples.
An analog sound wave is continuous so the more times you sample it per second and the more information you have in each sample, the cleaner and more precise the resulting audio becomes. In other words, a lossless digital audio track with a high sampling rate and a high bit depth has the potential to sound closer to the original studio recording than a lower quality track.
Of course, even if HD audio's benefits are clear on paper, there's still a chance that you simply won't notice the upgrade that these higher technical specifications provide. Since some people have more discerning ears than others, the improvements can be subtle for some listeners and more dramatic for others.
Before going too much further, you should take a quick hearing test to see if you can identify higher quality music, or if standard quality is adequate for your needs. NPR has a short six-question quiz that compares lossy audio to uncompressed WAV files from various genres. While those specific samples shouldn't serve as a definitive demonstration for what all HD audio can offer, if you can correctly identify the uncompressed tracks, then HD music might be more worthwhile for you.
What do I need to listen to HD audio?
The good news is that you can technically listen to lossless HD music on any pair of speakers or headphones — the bad news is that depending on the gear you own, it's possible that you won't be able to take full advantage of HD music's benefits.
In fact, you can't just connect your wireless headphones to an iPhone and get high definition music delivered in sparkling clarity to your ears. To ensure the best quality, you'll most likely want to invest in a digital-to-analog converter, or DAC, that connects to the device you're listening on. This device will provide optimized processing for HD tracks, especially those that feature high-resolution sample rates and bit depths. You'll also want to stick with a wired connection to your headphones or speakers in order to ensure the best playback quality.
If you do want to stay wireless, there are some Bluetooth devices that are capable of HD music playback, but you'll want to check with specific manufacturers for specifications. In most cases, you'll need devices that support aptX HD or Sony's LDAC codecs to maintain CD-quality sound.
In general, Wi-Fi solutions have the potential to provide a better HD audio experience than Bluetooth. Sonos speakers are capable of streaming CD-quality music via a Wi-Fi connection. Denon's HEOS audio components, Yamaha's MusicCast products, and DTS Play-Fi compatible gear can also provide the necessary playback support for CD-quality and hi-res.
The three major HD audio streaming providers, Amazon Music HD, Tidal, and Qobuz, all provide lists of partnered brands and devices that you can use to enjoy their HD music tracks.
Where can I listen to HD audio?
There are several streaming services currently offering HD music options, including Tidal, Amazon Music HD, and Qobuz. Each of these services reaches the minimum requirements for CD-quality while also providing even higher quality streams, referred to as hi-res, Ultra HD, master audio, or studio audio.
Here's a rundown of the individual plans for each HD streaming service:
- Tidal HiFi - $19.99 per month
- Amazon Music HD - $14.99 per month ($12.99 for Prime subscribers)
- Qobuz Studio Premier - $14.99 per month
Both Tidal and Amazon HD offer family plans for HD music, but Qobuz only has an individual plan. In addition to CD-quality HD audio, each of the above subscription plans also offers the ability to stream in even higher quality.
Amazon Music HD's highest quality tracks are called Ultra HD and they offer a bit depth of 24 bits, sample rates rup to 192kHz, and an average bitrate of 3730kbps. Like Amazon, Qobuz's highest quality music also tops out at 24 bits and 192kHz. Meanwhile, Tidal's highest quality streams feature MQA technology with up to a 96kHz sample rate and bit depth of 24 bits.
If you'd like to buy and download individual HD songs instead of paying for a streaming subscription, Qobuz and HDtracks both offer digital HD music stores.
Are there any downsides to HD audio?
There are some key hurdles to getting the most out of HD music, particularly if you're on a budget. The main downsides for HD music include:
- Higher prices for HD plans on streaming music services
- The very best playback requires more expensive gear
- More internet data is used for streaming
- HD music downloads take up more space
The flip side is that if you can hear a difference and appreciate the finer details with HD Music, it can be hard not to listen to music at the best quality possible. So, if you're someone who truly appreciates the higher fidelity and greater accuracy that HD music can provide, then the format is likely worth the cost of admission.
Thankfully, Amazon Music HD, Tidal, and Qobuz all offer free trial periods so you can sample the benefits of HD music to see if it's worth the added cost with your gear.
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