updated 01:58 am EDT, Sun March 30, 2014
High-resolution audio looks set to make an impact in 2014
If you think that high-resolution audio includes music ripped from typical CDs in lossless formats including FLAC and ALAC, you'd be wrong. The term refers to music that has a higher sampling frequency and bit depth than standard CD recordings, which are mastered at a bit depth of 16-bits and with a sampling frequency of 44.1kHz. FLAC and ALAC, however, do support music recorded at resolutions equivalent to those used in studio recordings, which is better than CD-quality. In recent times, a growing number of sites have started offering music in studio quality giving listeners the opportunity to listen to music literally as the artist intended.
While FLAC and ALAC ripped from typical 16-bit CD's easily beat out 256kbps AAC files and 320kbps MP3 recordings for fidelity, they still do not have the fidelity of most studio recordings that are typically captured with a bit depth of 24-bits and a sampling frequency of 96kHz or 192kHz. 24-bit FLAC and ALAC files. Although 'lossless' formats still compress music files, that in their uncompressed form would be double the file size, they still preserve the fidelity of the original recording. As such, audiophiles are happy to 'settle' for 24-bit, 96kHz FLAC or ALAC files, as even though they take up more hard disk space that AAC (MP4) and MP3 files, they preserve the fidelity of the original recordings. Uncompressed 24-bit, 96kHz digital file formats include AIFF, WAV, and DSD.
One company that has jumped in early to capitalize on the growing interest in the digital distribution of high-resolution audio is Sony, which has introduced a new range of high-resolution audio gear, including the new Android-powered NWZ-ZX1 High-Resolution Audio Walkman that we recently had the opportunity to go hands on with. It supports FLAC and ALAC files at 16- and 24-bits with sampling frequency rates of 88.2kHz, 96kHz, 176.4kHz and 192KHz, making it one of the few portable devices able to offer listeners an unadulterated listening experience. However, having an optimal recording and playback device isn't the whole story; you will also need headphones capable of supporting the frequency ranges produced by high-resolution audio players, which Sony is also producing to support its new range of high-resolution audio products.
We recently attended a Sony launch event for its new high-resolution audio range and where Sony audio guru and Chief Sound Engineer Koji Nageno was on hand to explain the benefits of high-resolution audio. Nageno is primarily responsible for the design and development of Sony's headphones, including the highly regarded MDR product range, which has recently been expanded to support high-resolution audio. While, on average, humans can hear frequencies from 20-20,000Hz, high-resolution audio formats can support frequency ranges between 5Hz-40,000Hz. Although, clearly out of the hearing range of most people, Nageno argues that it has been shown that even if humans can't hear all the frequency ranges of high-resolution audio, they can still feel much of them affecting the overall listening experience. Furthermore, 70 percent of Sony customers surveyed expect better than CD quality on Internet and mobile devices.
Sony, of course, missed out on the digital music revolution, at least from a hardware perspective, as Apple went on to dominate the personal music player market in the 2000's with its massively popular dual iPod and iTunes strategy. For the first few years, iTunes digital sales consisted of 128kbps AAC files before 256kbps AAC files were introduced in 2009. Although near CD-quality, 256kbps files are considered 'lossy' and of a reduced resolution compared to CDs, though for most people, they produce a sound quality that is more than adequate. The fact that so many iPhone and iPod owners persist with Apple's ear buds is proof enough of this, when the purchase of a decent set of ear buds or headphones will improve even this experience considerably. (I will concede, however, that Apple's EarPods are much improved.)
The main reason digital audio file formats have favored 'lossy' formats like AAC and MP3 is because of their much reduced file sizes. A typical high-resolution audio file for one song can be large as 150MB, whereas a 320kbps MP3 file is just 10MB in size by comparison. However, as bandwidth has now increased considerably for many people around the globe, interest in high-resolution audio has been rekindled. The explosion in popularity of the mid- to high-end headphone market in recent years shows that there is an appetite among many consumers for a better listening experience. Both LG, Sony and Samsung have moved towards supporting 'lossless' formats like FLAC and ALAC in their next-generation smartphones in an attempt to win over new customers interested in getting the best listening experience on the go. Apple's iPhone 5s also supports ALAC, AIFF and WAV.
While there is a lot of debate about the benefits of high-resolution audio over CDs and even FLAC and ALAC rips of CDs in terms of the improvement to the listening experience, in my experience there can be marked differences between listening to CDs and MP4s and MP3s. I have found the difference between listening to a CD and a lossless format can be negligible; however, I can appreciate the benefits of listening to a 24-bit, 96kHz high-resolution recording against listening to a 16-bit version of the same recording on CD. This has been made most obvious to me when making my own recordings in GarageBand or Logic in 24-bit, 96kHz and then listening to these exported in AIFF, ALAC as well as AAC. The expansiveness and resolution of the original recordings is certainly lost in 256kbps AAC, but is entirely preserved in uncompressed 24-bit AIFF and almost entirely preserved in uncompressed 16-bit AIFF exports.
The best way of capturing the differences in (at least) theoretical fidelity is to compare the respective file sizes produced of one of my songs when exported from GarageBand. An uncompressed 24-bit AIFF file came out at 57.1MB, while the uncompressed 16-bit version came out at 38.1MB. The 256kbps AAC version came out at 7.5MB. While it sounds fine in isolation, when compared to the uncompressed 24-bit file, it is well off the pace, sound much lowed in fidelity with the sound stage much flatter and more confined. Compared to the 256kbps transfer rate of an iTunes Plus AAC recording, a 16-bit CD recording transfers data at a rate of 1411kbps. An uncompressed 24-bit AIFF recording transfers data at a rate of 9216kbps, preserving all the sonic details of the original recording.
Clearly, for purists, having the all the gear that supports high-resolution audio files is the only option provided you have the budget to match. While one well-known headphone brand pushes the slogan that its products allow you to hear the music the way the artist intended, only devices and gear that supports high-resolution audio will truly give you that capability. Does it make a difference? Absolutely. My experience recording and exporting music in GarageBand and Logic leaves me in no doubt that you will get a studio quality listening experience listening to music in high-resolution formats. It is better than CD-quality and preserves the fidelity of studio recordings. It will be interesting to see how big this new market will get over the coming years, any there is no doubt that it is set to grow. I doubt that it will become the norm for some time, if ever, but it is certainly appealing for the many music lovers out there and well worth investigating further.
Update: Appleinsider is reporting that Apple may introduce 24-bit downloads later this year as part of a wider revamp of the iTunes Store.
By Sanjiv Sathiah