High-res audio (HRA) has emerged as arguably the ultimate sonic selection for digital music fans, but what's it all about, what do you need and how can you get it? Allow us to explain.

2015 has seen high-resolution audio (HRA) hit the mainstream, thanks to the release of more devices and services that support the audio format.

From Neil Young's PonoPlayer to high-res audio support on the Sony Xperia Z3 and high-res streaming on Qobuz, there's been plenty of noise around HD audio.

But how did it all start and where is the market heading?

As the music industry shifted away from physical media such as CD and vinyl (the vinyl resurgence not withstanding), many of us moved to digital downloads from sites such as Amazon and iTunes, and latterly streaming services, such as Spotify.

These sites use compressed file formats with relatively and low bitrates, such as 256kbps AAC files on iTunes and 320kbps MP3 streams on Spotify.

And with regards to sound quality, these formats aren't telling the full story of our favourite songs. The use of lossy compression means that data is lost in the encoding process, which means resolution is sacrificed for the sake of convenience and smaller file sizes.

This might be fine on the bus when you're listening to your iPod or smartphone, but some serious music fans want better. This is where high-resolution audio – or HRA, the term coined by the Consumer Electronics Association – steps in.

Astell & Kern, LG, Samsung, Sony and FiiO are just some of the companies to have launched high-resolution audio compatible products so far, while several download sites now offer better-than-CD quality music files, with the likes of HDtracks and Qobuz now live in the UK. HRA also has the support of major labels and musicians.

But what does high-resolution audio actually mean? Where can you get it? And what do you need to play it on? Don't worry – all your questions and more are answered on this page. 

What is high-resolution audio?

Before we address this, it’s worth pointing out that the definition of high-resolution audio isn’t set in stone. Unlike high-definition video, which has to meet certain criteria to earn the name, there’s no universal standard for high-res audio. 

But it tends to refer to audio that has a higher sampling frequency and bit depth than CD, which is 16-bit/44.1kHz. High-resolution audio files usually use a sampling frequency or 96kHz or 192kHz at 24-bit, but you can also have 88.2kHz and 176.4kHz files too.

Sampling frequency means the number of times samples are taken per second when the analogue sound waves are converted into digital. The more bits there are meanwhile, the more accurately the signal can be measured in the first place, so 16-bit to 24-bit can see a noticeable leap in quality.

The Digital Entertainment Group, Consumer Electronics Association and The Recording Academy have, together with record labels, come up with a formal definition for high-res audio

As well as the definition - "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" - there are four different recording categories based on the source of the file.

There are several high-resolution audio file formats to choose from, all of which support the above sampling rates and bit-depths. They include FLAC (Free Lossless Audio Codec) and ALAC (Apple Lossless Audio Codec), both of which are compressed but in a way that (in theory) no information is lost.

Other formats include WAV, AIFF and DSD, the format used for Super Audio CDs. The relative merits of the formats can be argued but most crucial will be compatibility with your particular products and system.

FLAC tends to be the most popular, scoring points over WAV for better meta-data support, ensuring your tracks have artist and title information. There's a healthy debate on the What Hi-Fi? Forum on the subject of FLAC vs. WAV.

Of course, as well as downloading your music in these superior formats, and now streaming, you can - and should - also rip your existing music library in these higher-quality file formats.

What’s so good about high-res audio?

Obviously the main claimed benefit of high-resolution audio files is superior sound quality over compressed audio formats.

To illustrate why they should sound better than MP3s, for example, let’s compare the relative bitrates. The highest quality MP3 has a bitrate of 320kbps, whereas a 24-bit/192kHz file is transferred at a rate of 9216kbps. Music CDs are transferred at 1411kbps.

24-bit/96k or 24-bit/192kHz files should therefore more closely replicate the sound quality that the musicians and engineers were working with in the studio.

With more information to play with, high-resolution audio tends to boast greater detail and texture, bringing listeners closer to the original performance.

Though, as always, there are some people that can't hear a difference. As with all the products we review, if you can't see or hear a difference, then save your money... 

MORE: High-res audio - the science behind the numbers

Where to buy and download high-res audio?

There are currently a handful of UK download stores and several US and European sites, though not all of them let you purchase from the UK. Here are a few of the best:

HDTracks

Pioneering US high-resolution music store HDTracks is now available in the UK, initially launching with more than 10,000 uncomprossed high-resolution albums.

The company says it has partnered with every major record label – including Sony Music Entertainment, Warner and Universal – to create the world's largest catalogue of high-res audio files.

HDTracks has also announced a deal with Liztic, a music management application that aims to deliver a seamles digital music experience across PC, Mac, Android and iOS.

Naim Label

Better known for its home entertainment systems, Naim has a nifty sideline in hi-res audio files, including music from its own Naim Label.

Its site offers music in 320kbps MP3s right up to 24-bit/192kHz WAV, FLAC and ALAC files. High-res albums cost between £9.99 and £16.99.

Linn Records

Linn’s website offers what it calls Studio Master downloads in 24-bit/192kHz FLAC and ALAC, as well as 24-bit/96kHz, 16-bit/44.1kHz and 320kbps MP3 formats. A Studio Master album costs £18, or £10 in CD quality.

Bowers & Wilkins Society of Sound

Another hi-fi brand that turned its hand to hi-res downloads, B&W’s site boasts a range of studio-quality albums. You can also subscribe and access albums not available in the store. Files are available in 24-bit and cost £15.

PonoMusic

Neil Young's long-awaited Pono high-res service looks finally set to launch, with news that a Kickstarter campaign will make the PonoPlayer available to buy. The PonoMusic service promises DRM-free high-res downloads from major and independent labels and there's a dedicated music management software application, too. You can read our first impressions of the Pono PonoPlayer for more details.

Qobuz

French website Qobuz launched in the UK back in August and offers in excess of 20,000 high-resolution albums. Files are available at a minimum of 16-bit/44.1kHz while many are offered in 24-bit/192kHz. High-resolution files are also available through the Qobuz streaming service.

Technics Tracks

Building on the return of the brand in the form of new AV products, Technics has also launched a download store, complete with high-resolution music. The store claims 'tens of thousands' of tracks are available.

Onkyo Music 

Onkyo Music meanwhile claims 'hundreds of thousands' tracks for download, and is now live in the UK, US and Germany.

Other sites: 

2L – Norwegian site offering up to 24-bit/96kHz and multichannel DSD

7Digital – Offers 24-bit FLAC downloads

Gimell – Studio Master 5.1 downloads in 24-bit/96kHz

HD Klassik – Classical music high-res downloads

Sony, Warner and Universal have also announced that they will make their extensive music catalogues available to hi-res download services – all of which is a real shot in the arm for fans of high-resolution audio in this country.

With all sites, make sure it's clear what file format and bitrate you are buying and let us know your experiences with using these and any other HRA websites in the comments below.

High-res streaming?

Tidal and Meridian demo high-res streaming

We've now seen the launch of CD-quality streaming services, with Tidal and Qobuz launching in to the market offering lossless audio streams.

This delivers a step-up in quality over the established services such as Google Play Music, Rdio and the market-leader, Spotify. And indeed the new Apple Music streaming service.

But it's not strictly high-res audio, which refers to better-than-CD-quality files.

There is one exception - if you have an Android phone you can stream high-res audio on Qobuz.

Tidal and Meridian have also successfully demonstrated streaming high-res audio, using Meridian's MQA format. But there's no sign of an official public launch yet. It could be that Meridian's MQA format is key for any further high-res streaming services.

MORE: Meridian Audio MQA paves way for high-res streaming

What do I need to play it?

From AV receivers and stereo amps to all-in-one music systems and streamers, a growing number of products on the market are handling high-resolution audio. 

As yet, there remains a certain amount of variation when it comes to file handling and maximum bitrate support on different devices, so check the specifications match your requirements before you buy a new product.

Some systems allow you to play high-res files directly from USB storage devices or from a networked PC via Ethernet. 

You can also play high-resolution audio stored on a PC by connecting it to a USB DAC like the Arcam irDAC (pictured, above), the Naim DAC-V1 or the T+A DAC 8, then feeding it to a power amp, powered speakers or headphones.

Complete systems, such as the Monitor Audio MA100, now support high-res audio (as well as wireless streaming features), while companies such as Sharp have also got in on the act.

You can even buy dedicated headphone amps with built-in DACs that handle high-res audio. The ever-popular Sonos system supports WAV and AIFF files but only up to uncompressed CD quality.

However, you will need a high resolution audio player, as not all music software is compatible. iTunes will play high-res files but not FLAC files, for example.

If you're on a Mac, you can try Amarra or Channel D's Pure Music. We also hear differences in sound quality, so it's worth experimenting. On a PC? Try JRiver Media Center

High-res music on mobile

High-res audio isn’t just confined to the hi-fi market. Several of the latest smartphones play music in sparking 24-bit/192kHz quality, including the LG G3Sony Xperia Z3 and Samsung Galaxy Note 4, while the Onkyo HF Player app allows you to play high-res music on any compatible mobile phone.

The iPhone 6 sadly doesn't support high-res audio out of the box but there is the potential to connect devices via the Lightning output rather than the headphone jack to send a digital audio signal.

The Philips M2L headphones are the first to use the Lightning connection, bypassing the iPhone's internal DAC to instead use their own high-res capable DAC.

And Qobuz has provided a world first for Android mobile users: the ability to stream high-res music on your phone via its streaming service.

More after the break

Best high-res audio streamers

Best music streamers under £600

Bluesound Node

Five stars

Tested at £400 / compare prices

"An all-round multi-room music, high-res beauty, from sound to features to design."

 

Pioneer N-50a 

Five stars

Tested at £500 / compare prices

"A superstar, improved. Pioneer has done it again."

 

Best music streamer under £1000

Cambridge Audio Stream Magic 6 V2

Five stars

Tested at £700

"The best at this price made better – the Stream Magic 6 V2’s added functionality makes this a better proposition than ever."

 

Best music streamer under £1500

Cyrus Stream Xa

Five stars

Tested at £1250 / compare prices

"If you're looking for a premium streaming option, the Stream Xa is a fantastic proposition."

Best music streamer £2000+

Cyrus Stream XP2-QX

Five stars

Tested at £2300

"This superb streamer sounds absolutely fantastic"

Best portable high-res music players

High resolution audio doesn't have to be saved for home listening anymore. Companies such as Sony and Astell & Kern believe we should be able to access high-resolution audio on the move, and as such, have produced portable high-resolution music players. Here are our favourites, in price order. Click through for the full reviews, latest prices and more details.

 

Acoustic Research M2

Four stars

£900

If you're looking for a premium portable high-res player, then the M2 deserves a listen. 

 

Astell & Kern AK100 Mk II

Four stars

£700

We’re very impressed with the Astell & Kern AK100 MkII, but there are issues. We’re pleased to see DSD support, but that’s offset by the sluggish interface. 

 

Sony NWZ-F886

Five stars

£240

One of the best portable high-res music players on the market today, the F886 delivers high-resolution tracks with supreme precision. The fact it's built around the Android operating system, granting access to the app store and web browsing, makes it a lot more desirable. 

MORE: Sony NWZ-F886 review

 

Sony NWZ-A15

Four stars

£170 / compare prices

If you’re not after flashy features and merely want to dip your toe into the high-resolution water, this is a very good place to start.

 

See all our portable music player reviews 

Upcoming music players

Astell & Kern AK240

Unveiled at CES, the flagship Astell & Kern AK240 was one of our Stars of CES winners, and features a 256GB internal memory and a microSD card slot supporting up to 64GB of extra storage. It can play DSD files without having to convert them, and will also stream music from a NAS device.

 

Sony NWZ-ZX2 

£950

Sony's new £950 NWZ-ZX2 Walkman was one of the big announcements at CES 2015. The initial signs appear promising - but then for this sort of money you'd certainly hope so.

Just how good it is and whether it can justify the price tag for a portable music source remains to be seen. You can read our ZX2 hands-on review.

 

Pono PonoPlayer 

$399

 

First impressions of the PonoPlayer, complete with an unboxing video, this is the portable high-res music player that's part of Neil Young's PonoMusic high-res ecosystem. Read our PonoPlayer hands-on review.

Multi-room high-resolution audio

Multi-room audio products have seen a major boost in 2015, with many manufacturers looking to expand their product arsenal's or new manufacturers looking to steal the limelight away from current multi-room audio champion, Sonos.

Bluesound entered the market in 2014, promising high-resolution, 24-bit audio across the entire range - and we've been seriously impressed by the results. Products in the range include the Node wireless streamer, Powernode standalone streaming music player, Vault high-resolution music server, Pulse all-in-one music streaming system and Duo 2.1 speaker system and subwoofer. 

MORE: See all our Bluesound reviews

Sonos can only stream in CD-quality 16-bit/44.1khz.

Other multi-room audio systems have followed the lead of Bluesound, with systems such as the LG Music Flow, Lenco PlayLink, Harman Kardon Omni and Monster SoundStage all offering high-res support on their new wireless speaker systems.

MORE: Multi-room audio: everything you need to know

What's next?

Since receiving its own dedicated zone at CES, high-resolution audio gained a lot of traction in 2014 and in to 2015.

Manufacturers including Bowers & Wilkins, Naim and Linn have been pushing for and producing high-resolution audio products for some time. We've now seen mass-market heavyweights such as Sony, LG and Samsung adopt the format to bring it to a larger audience. 

With this wider availability, more people are able to learn and understand exactly what high-resolution audio is, and the benefits it brings to music listening. There's plenty of content out there - and now we have the hardware to go with it.

Moving through 2015, we expect more manufacturers to produce more affordable high-res audio products, as high-res becomes a standard feature on music players, streamers and more, giving consumers the choice to get involved, should they value the potential jump in audio quality.

OPINION: The science behind the high-res audio numbers

 

Comments

StanleyAV's picture

DRM/copy protection within the analogue audio???!!

How do we know that Sony with its technology and downloads has not
secretly placed "audible"(?) watermarks within the analogue domain?

It is quite happy to pollute the audio for Cinavia enabled Blu-Ray releases?
I can see that dirtying the audio for hi-res would be unconscionable
for audiophiles but sorely tempting for Sony and the record industry.

Thoughts, Whathifi?

narfybob's picture

False advertising

"Obviously the main benefit of high-resolution audio files is their superior sound quality over compressed audio formats and CDs. ... With more information to play with, high-resolution audio tends to boast greater detail and texture, bringing listeners closer to the original performance than ever before."

This is completely false. Where did you get the information that higher-resolution music automagically means it sounds better? Scientifically published findings, basic electrical engineering concepts, and myriads of ABX testings have demonstrated humans can't distinguish between a high-resolution music file and that same file down-sampled to CD quality.

 

Bit depth only affects quantization error noise, and thus the noise floor. A bit depth of 16 already has a low enough noise floor and dynamic range for even very dynamic classical music for consumer playback. Were music to utilize the full 24-bits of resolution available in a 24-bit recording, the music would have enough dynamic range to seriously damage our hearing. Such bit depths are only useful for studio applications where the engineers work and with the audio signals and the extra headroom is required for sound manipulation, NOT for the sound quality.

 

Sample rates of 44.1 kHz or higher do nothing useful to the end listener since the Nyquist sampling theorem states that a signal can be perfectly replicated with a sampling frequency twice as much as the highest frequency captured. Human hearing has a limit of 20 kHz, if not less due to age and deafness. That means a signal can be accurately captured with a sampling rate of 40 kHz. It's been demonstrated through scientific testing that high-frequency reproduction in audio equipment can be harmful to the sound quality since aliasing from the higher frequencies folds into the audible range.

 

I highly suggest doing some basic research first before you publish this propaganda.

http://xiph.org/~xiphmont/demo/neil-young.html

http://www.aes.org/e-lib/browse.cfm?elib=14195</p></div>

http://www.aes.org/e-lib/browse.cfm?elib=13967

http://www.ece.rutgers.edu/~orfanidi/intro2sp/orfanidis-i2sp.pdf

http://en.wikipedia.org/wiki/Nyquist_sampling_theorem

http://en.wikipedia.org/wiki/Audio_bit_depth

http://www.innerfidelity.com/content/its-masters-damit

http://www.youtube.com/watch?v=nLEhfieoMq8

http://www.sonicscoop.com/2013/08/29/why-almost-everything-you-thought-you-knew-about-bit-depth-is-probably-wrong/

http://audioxpress.com/files/galo2941.pdf

 

 

This is exactly why the Pono Player has so much resistance amongst the hi-fi folks. They have the right intentions, but they're using and actively advertising the wrong information to the common consumers and media outlets, so they are in essence being fed false advertising. It's absolutely KILLING us people who actually know better!
As stated in the Innerfidelity article, one user commented:
"What will ultimately happen is that they will damage the hobby and industry as a whole with this misleading advertising."

offskooring's picture

so...what you guys have to

so...what you guys have to say seems pretty legit...my question would be...what should i focus on for quality playback of digital files?

Killian O'Sullivan's picture

The loudspeakers, their

The loudspeakers, their placement and a half decent amplifier!

william meredith's picture

Totall agree.

Totall agree.

please do the research before wasting money on hi-res audio.  do the blind test at test.tidalhifi.com.  Do it many times.  If you get 5/5 once in 10 tries, it doesn't mean you can hear the difference, it means you are guessing and statistically you will sometimes get 5/5.

Sampling rates of 44.1KHz are more than sufficient.  They can totally accurately reproduce frequencies up to 22Khz.  If you think you can hear or "sense" frequencies near or higher than 22KHz, then do a hearing test.  Even at 22Khz, we are building systems that 8 year olds might appreciate, but most audiophile 40 year olds will hear total silence above 16KHz.

Bit depth of 16bit is more than sufficient.  Increasing bit depth to 24bit, and you will be able to play the loudest parts of the Berlin Philharmonica playing Beethoven's 9th.  Turn your system up to almost unbearable levels and the 24bit resolution will allow you to hear the cellist farting.  But that's also beyond the limits of human ability.  Most 40 year old audiophiles have trouble hearing someone talking in a noisy café.

It's not hard, or expensive, to find a DAC that removes jitter and produces almost perfect output.  Rip your CD collection to FLAC, buy CD-quality files onlines.  Spend your money on an amplifier and speakers.  

 

Killian O'Sullivan's picture

False advertising

Totally agree with Narfy bob. The science says that it is complete overkill. I once heard another Engineer joke that if you had 24 bit material that used its full dynamic range, the quietest passage would be totally below the threshold of hearing while the loudest part would cause instant death due to the SPL level pulverising your body and demolishing the building that you are in.  The oversampling to 192KHz is also overkill given that the limit of human hearing only goes to little over 20KHz. Any perceived difference by reviewers is likley down to better mastering of the material rather than the higher resolution format. Unfortuately, those peddling this stuff are pandering to the herd.

 

Lazy-1's picture

Wimp HiFi ...

... is another CD quality streaming service that deserves mention. Flac and Alac.

Update: Launched as Tidal.

jimbo20004000's picture

Sound Quality

Narfybob is correct. I have worked in various studios over the years. 16/44.1 (or 48) is high enough sample rate and resolution to cover anything a human can appreciate. Especially when using consumer quality audio reproduction equipment. We use much higher quality mastering equipment; for example PMC active speakers which cost many tens of thousands of pounds. Play a CD quality track through those and trust me they give all the detail, dynamics and overall sound quality you could wish for. 

16/44.1 sound quality is dictated by the quality of the audio recording process. Simply increasing the resolution and sample rate will not magically increase sound quality. Analogue to digital conversion and the whole editing process has greatly improved since the eighties, which is why CD's mastered back then did not always sound so good. These days a well mastered CD or FLAC equivalent will sound exactly the same as the 24/192 version. I listen through 100K worth of PMC active speakers, and we cannot tell any difference. We do record much higher than the 16/48 we used to, to allow easier editing; but i can asure you no perceivable sound quality is lost when converted down to 16/44.1.  

The Nyquist sampling theorem does indeed apply. It is basic mathematics and physics applied to audio. No marketing talk here i am afraid. Also no DAC or ADC can resolve a full 24 bits as the last few bits of data are lost in noise/distortion. (until they can develop a room temperature superconductor that is). Anyone with an understanding of electronics/maths and physics will know this.

 

kain50144's picture

Data

Unfortunately i have to slighty dissagree with you and everyone talking about this on a few points. I am not a expert in music or audio recording. But my profession is data, and the simple fact that you are losing data means there is a significant difference in quality no matter what. It's the reason that high quality audio and video is a larger size and sounds better, it contains more information. from a frequency standpoint you are correct but from a data standpoint you guys couldn't be more wrong. You are guys trying to say 42-42=42 it just isn't correct.

Nathan Bookham's picture

I also work in the audio

I also work in the audio industry and you are talking absolute garbage backed up with no science whatsoever.

What you're saying is "My Blu-Ray player and TV don't emit UV light, so it isn't the original image!1!!!"

Ah Lau's picture

CD vs Hi-res

CD quality bit rate is 1.411Mbps, the 192kHz/24bit Hi-res audio bit rate is 9.216Mbps. it means the audio signal is 6.5X more data compare to CD.. the audio signal is more close to true audio....  

jimbo20004000's picture

Reconstructing the analogue

Reconstructing the analogue signal is not made more accurate by increasing bit depth and sample rate, and it will NOT increase sound quality. 16/44.1 covers the frequency range and dynamic range required for human hearing limitatations. Increasing data rate does not increase percievable sound quality. The Nyquist sampling theory covers the mathematics to prove this. It is the recording process and then the reproduction process which determines overall sound quality. The reason some recordings higher than 16/44.1 may sound better is because they were recorded and produced to higher standards in the first place. They use a higher quality master. To put it another way, a recording made at 24/192 can sound worse than one at 16/44.1. 

http://mathworld.wolfram.com/SamplingTheorem.html

This short educational video explains and proves why 16/44.1 is easily enough to record and reconstruct the original analogue waveform. Increaing bit depth simply increases dynamic range and lowers noise, which is ok for studio use; but 16/44.1 is already low enough noise and high enough dynamic range for human hearing limitations. Increasing sampling rate to 96 or 192Khz is pointless, as all it does is introduce problems such as intermodulation distortion. It makes zero difference to the accuracy of the original analogue waveform being captured. Anyone with a basic understanding of electronics and mathematics knows this. Hence the comment that increasing bit depth and sampling rate will more accurately capture the original analogue waveform, is not mathematically correct.

http://xiph.org/video/vid2.shtml

http://people.xiph.org/~xiphmont/demo/neil-young.html

http://en.wikipedia.org/wiki/Nyquist%E2%80%93Shannon_sampling_theorem

offskooring's picture

so...what you guys have to

so...what you guys have to say seems pretty legit...my question would be...what should i focus on for quality playback of digital files?
 

wombledon's picture

Just done a comparison with

Just done a comparison with 320kbps mp3, CD, and HD version of the same track, and with reasonable headphones (Sennheiser HD565) and Traktor Audio2.

Each step up in quality sounds cleaner, more precise stereo imaging, just more life-like. 

Sampling rate of 2x the highest frequency obviously isn't as good as it gets for those with discerning ears.

andyjm's picture

Maths is maths, and unless

Maths is maths, and unless you are a medical phenomenon, then 20Khz, 96dB (CD's range) is enough for anyone. 

That's not to say the tracks you tested didn't sound different.  Most differences in tests like yours come down to different masters.  Unless you started with the HD track and made the 16/44.1 and the MP3 track yourself, then there is every chance that the starting point of the 3 versions was different.

It is also not a given that your hardware does an equally decent job of reconstructing the 3 versions. Perhaps the designer spent more time worrying about the hires portion than the CD quality chain.

When properly conducted tests are performed, with music sourced from the same master and played back through level matched equipment, there are no tests to justify that 24/96 can be distinguished from 16/44.1 

I am afraid that the truth is that it is just marketing.

 

alex30's picture

Smoke and Mirrors

I totally agree with all the posters who point out that no one can tell the difference between Hi Res or Ultra Res and CD quality recording. The extra frequencies are beyond the range of human hearing. This is not debatable. It is fact.                                                                                      I do disagree that it will ruin the industry. The Hi Fi world has long been beset by myths , legends and lies. Take , for example , the whole unscientific approach and witchcraft surrounding the promotion of  loudspeaker cables and interconnects. These simple pieces of wire are said to open up the sounstage, add detail, precision and dynamics. But only if you pay an exorbitant fee so that you can join a select few and own our cables. Can anyone , who has not been certified insane, please explain to me how a cable can improve sound staging? I have news for you, it is not possible.                                                                                                                  Music will survive this latest attempt to scam us out of our money but it does those involved no credit at all.

itleoc-shop2@yahoo.it's picture

Nyquist was not a Musician.

Nyquist was not a Musician.

if you sample a 20khz sinusoid waveform at 44,1 khz you will get a triangle waveform. this not sound the same as sinusoid. this is mathematic , this is music. 

Musicscience's picture

Nyquist theorem

The triangle waveform can reproduce exactly the 20Khz sinusoïde. How? Any periodic waveform is made of mixed pure sinusoïdes mainly multiples (2 , 3, 4, ....) of the basic frequency (that is Fourier's series).

So the triangle waveform has a basic frequency of 20Khz and is made of a basic sinusoïde of 20Khz and many sinusoïdes multiples of 20Khz (40Khz, 60Khz, 80Khz, .....). Then a filter eliminates all sinusoïdes above 20Khz. I know it is hard to believe or understand but it is mathematics and it works. 

At a sampling rate of 192Khz you have the same problem: instead of 3 points you have at most 15 points to represent your 20Khz sinusoïde; it is smoother but still far from a perfect sinusoïde. And this periodic waveform (the 15 points) is also made of a basic sinusoïde of 20Khz and many sinusoïdes multiples of 20Khz (not the same ones as the triangle waveform above). After filtering (eliminating all sinusoïdes above 20Khz) you recover your perfect analog 20Khz sinusoïde.

So is the Nyquist-Shannon THEOREM. And in maths a THEOREM is a proof.

Graham Luke's picture

Innit...

I'll get me coat...

bigfish786's picture

i think the music industry is

i think the music industry is trying very hard to entice us into buying the "next big thing" in audio. 

my ears tell me that vinyl played on something half decent sounds way better than cd. 

i'll be investing in vinyl, not in downloads,or streaming. it does nothing for me.

vipperofvip's picture

sound, how it feels

Geat chat guys!                       not all sound is =   that is why we call it sound or noise!

music is to be experienced, but not all music is to be experienced in the same ways.       i play a few insterments, as some one who has played stringed insterments most of my life,  i can say without a doubt,  not all violins, guitars etc are equal. most will agree.  woods etc play a part in how it sounds and playability,  ie some insterments are shit! and will always play and sound shitty!  so as head phones amps etc.   i think some people get confused with sound. i call it tone color.  all music destortion, live, analog, digital, but it is up to the artest to use any of it for his advantage. vinal has a dark sound with pops, cd has a crisp bit sound. 59les paul is open acousticish fuz sound, tube amps have a worm cumpling sound transistors have a harsh rippig sound.  enjoy all of it and depending on the way you like to experiance music, treat it like a great insterment and you wil be shocked.

 so now we have it.  human ears hear a wide range of sound waves, music wise we convert to tone.  lower sampled music will have all hz khz  but when in digital wave form chunks of waves gets crushed, ie, we miss out on the  nuances of joe' rid in the song take 5. but when we are talking deadmous5, more base mid and hi experiance  great to.

i am sure when vinal records came out people bitch that is does not sound live.  (thanks KISS for the live album! smart!)  and in reverse, people go to see live music and bitch how it does not sound like the cd.  lol

 

not all samle rate or bit rates are = but can be enjoyed, the way they are intended 

 

arjguitarplayer's picture

High-resolution audio: everything you need to know Read more at

Everything here is extremely precious - thank's a lot. I'm very greatfull and impressed about the high quality of all comments. I'm very pleased and proud to learn more and more about a subject that inspires passion, cause Music, indeed, I trust. Actually, We all trust. Simply Gorgeous.

Lazy-1's picture

Comments on High-res sound

Considering the amount of energy spent on this subject I suggest that an attempt should be made to establish some conclusions.

We have powerful statistical tools at our disposal that can be used to reach conclusive results provided that the trials are properly designed and executed.

Core hypothesis:

"common man will prefer High-res music over non-HR music"

What Hi-Fi -- why not lead the way here?

 

Jacques Barrière's picture

Real Studio Masters

What's killing music is CDs masquerading as masters. Any tit can, with a program falsify a CD to 24 with the click of the mouse. A great CD master sounds great on a good resolving system but a real Studio Master is jaw dropping in all areas. If you cannot hear the vast difference in musicality, it sucks to be you. I do applaud Meridians attempt to bring us authentication of the ALBUM with the up and coming MQA decoding technique. All you have to do after all.....JUST LISTEN

Deafasapost's picture

Any suggestions for HI Quality Music Systems

Well it seems we have a bunch of experts, and I really cant disagree with anything thats been said above, for one thing I dont have the inclination/technical expertise but i have a set of (ageing) ears and have money to burn on a good quality ,all in one, or as few boxes as possible music system. I already have a mixture of kit, like many people lured into MP3 etc etc, have mac computers/itunes library, Bose music sytem with attached Brenan JB7 which contains the majority of my old cd collection.  Ive been reading the above trying to decide whether to invest in a high quality music streamer. So what would the experts choice/recommendation be for me to look at /hear. Budget is not a key issue for me, on the other hand i dont want to epend for kit thats is not really going to make any difference other than my budget!!! Thanks

 

 

Andy Clough's picture

Music streamer

Our April 2015 issue, on sale from March 11th, contains an eight-page feature on high-res audio and includes a number of recommended streaming systems, so it would be well worth taking a look at that.

You can also check out some of our Best Buy streamers here:

http://www.whathifi.com/best-buys/music-streamers

HiFideliste's picture

About new VINYL Records?

If a new Vinyl record is produced from a recent digital recording, why should it sound better than the 24 bits/ 96 KHz (or higher definition) FLAC file and even the CD format (16/44.1) release?   Are there still analog recordings for Vinyl?    
Molenaar's picture

my only reference

What a lot of tecnical bla, bla,bla from arrogant prigs who are telling me what I can hear and what not........My only reference are my ears, and believe it or not, I hear the difference!

If you don't here it, sorry for you but please find another hobby.........and let me enjoy HIFI!!

Best regards!

alex30's picture

You are deluded and full of Expectation Bias!

Do a proper double blind test with CD's mastered exactly the same as some HiRes material and you will not hear a difference as long as everything else is equal.                                               If , at the moment you believe that you can hear a difference it is because you expect to, or there is a difference is the mastering of the sources, or there is some other difference in the playing chain. It is not due to the incresed bit rate or frequency range because the human ear is not capable of hearing beyond a certain range, no matter how special you think your hearing is. No one is trying to tell you what you think you can hear, just what it has been medically proven that humans are capable of hearing. Just like no ones eyes can see ultraviolet or X Rays. Our senses are not up to the job.

dmans's picture

many factors

You have to give Neil Young some credit for starting this conversation. There is a parallel situation with photos that might be a bit easier to picture. Cameras, especially phone cameras are marketed as 10 megapixal, or 14 megapixal, or 23 megapixal, and the perception is that more pixels are always better. This totally ignores the lens which is a huge factor in the quality of the picture result. There are many factors at work that will determine the quality of a recording. Garbage in garbage out.