High-resolution audio: everything you need to know

(source: whatwifi.com)

In the last few years, "high-resolution audio" (or "hi-res audio") has slowly but surely hit the mainstream, thanks to the release of more products, streaming services and even smartphones supporting the hi-res standards. f you want the best digital music experience possible or, at least, better sound quality than you're currently used to, we think hi-res audio is worth investigating. Sampling frequency (or sample rate) refers to the number of times samples of the signal are taken per second during the analogue-to-digital conversion process. The more bits there are, the more accurately the signal can be measured in the first instance, so going 16bit to 24bit can deliver a noticeable leap in quality. Hi-res audio files usually use a sampling frequency of 96kHz or 192kHz at 24bit. You can also have 88.2kHz and 176.4kHz files too.

To illustrate why it should sound better than MP3, for example, let’s compare the relative bitrates. The highest quality MP3 has a bitrate of 320kbps, whereas a 24bit/192kHz file has a data rate of 9216kbps. Music CDs are 1411kbps. The hi-res 24bit/96kHz or 24bit/192kHz files should, therefore, more closely replicate the sound quality the musicians and engineers were working with in the studio. And they could be that very same recorded file, too - these files are labelled as "Studio Masters" in some cases. With more information on the file to play with, hi-res audio tends to boast greater detail and texture, bringing listeners closer to the original performance - provided your system is transparent enough.

Hi-res audio does come with a downside though: file size. A hi-res file can typically be tens of megabytes in size, and a few tracks can quickly eat up the storage on your device. Thankfully, storage is much cheaper than it used to be, so it's easier to get higher-capacity devices. That said, the size of the files can still make hi-res audio cumbersome to stream over your wi-fi or mobile network. They include the popular FLAC (Free Lossless Audio Codec) and ALAC (Apple Lossless Audio Codec) formats, both of which are compressed but in a way which means that, in theory, no information is lost. Other formats include the uncompressed WAV and AIFF formats, DSD (the format used for Super Audio CDs) and the more recent MQA (Master Quality Authenticated).