Hi Res Audio recordings - Well maybe?

[astral]

It should all be so simple. 'The higher the number the better the sound' is an easy message to communicate.

So, a 24-bit/192kHz recording must sound better than a 16-bit/44.1 kHz CD rip, right? Not quite, unfortunately – things aren’t as straightforward as that.

Even before you start listening there are a number of factors to consider.

1) What are the recording’s origins? We’ve come across so-called ‘high-resolution' recordings that are touted as 24-bit/96kHz or even 24-bit/192kHz, but are little more than up-sampled CD masters sold at rip-off prices. These are a con, pure and simple.

2) A high-quality original master recording is a must. If that is engineered poorly it doesn’t matter how high a resolution the recording is, it just won’t sound good.

3) Much depends on the playback equipment used. If that isn’t transparent enough to reveal the differences, you’ve got no chance of hearing them.

4) An open mind is useful, too. Standard resolution files are pegged at 16-bit/44.1kHz. This is the level of CD.

Anything higher than this in terms of bits or kHz is considered a high-resolution recording.

What isn’t made clear from the ‘high-resolution’ tag is whether the music file is exactly the same as the original.

This is why some companies prefer to use the label ‘Studio Master’ instead (where it applies, of course).

Making fair comparisons between high resolution/Studio Master files and CD quality alternatives

isn’t as easy as you might think. I've talked to a number of people in the recording industry,

and it looks like the two types of files aren’t necessarily treated the same.

It’s likely that the studios take more care over high-resolution files as they will tend to be heard and bought by more discerning users.

The CD-spec file will usually be a down-sampled version of that file.

Not only are there losses involved in stepping down the resolution, but it may well be engineered for less

discriminating uses such as commercial broadcast or car use, and so sound different too.

If we get past these issues (somehow), surely there’s a technical case for high-resolution recordings being better, right?

Once again the answer isn’t as obvious as we’d like.

Thanks to What HiFi

[KittenKong]

Most of the 24-bit/192kHz files I have came from SACD via a PlayStation3. I have them either in the original ISO format or as multi-channel FLAC conversions. Others are FLAC files made directly from hi-def studio recordings.

I am more than satisfied that they all offer much more audible detail than regular CDs do.

Upscaled files are another thing entirely, of course.

[rgs2001uk]

Lets be honest here, the record industry had been ripping us off for years and will continue to do so.

Dont even get me started on compression.

As long as people want to listen to mp3 lo bit crap on their mobile fine, as mentioned, listen to the same recording on a decent hi fi system and the limitations soon become apparent.

Genesis, remastered cds are a prime example, my brother pulled out the original vinyl albums and listened to them, he then listened to the remastered cds and could tell the difference.

The problem these days, we live in a disposable society, no-one keeps music for more than 1 month, bin it and move onto the next Simon Cowell crap hyped sensation.

http://news.cnet.com/8301-13645_3-10360787-47.html

[KittenKong]

Genesis, remastered cds are a prime example, my brother pulled out the original vinyl albums and listened to them, he then listened to the remastered cds and could tell the difference.

Try the Genesis SACDs.

[astral]

The Hi-Fi News magazine analyses the latest recordings each month

Even the ones sold in SACD format, may have mere CD origins, not all but quite a few

As they say in legal circles - Caveat Emptor, (Buyer Beware)

[IMHO]

if you can get your hands on actual studio masters, you will hear a difference between them and the 'retail' version - regardless of whether it's 32bit, 24bit or 16bit - assuming it's coming from a high-end studio and not someone's basement that is

That difference might not be what you want though - generally speaking, retail recordings have been tweaked and tuned to sound 'good' on the typical playback systems most people use, i.e. earbuds that come with popular phones/ipods, ipod docks, HTIB's, and generally low-mid end systems under around $5K USD.

Most studios will evaluate the final mix using multiple sets of low and mid-end studio monitors (speakers) so they can tune the retail version on systems that best approximate mid-low end consumer systems..... using their $50K++ monitors purely for the original master.

But, the catch is, if you don't listen on a very high end system, the master might not give you the sound you're looking for..

Generally speaking, the masters are recorded at a much lower nominal volume (to allow for higher dynamic range), feature no volume compression (so quiet passages might get too quiet to hear on a typical system with some background noise), and can even pose a danger to systems playing at 'nominal' volume levels, that just don't have the power & headroom to handle the bigger dynamics. They also lack the EQ the retail versions have that make more mediocre systems sound better (not just 'smiley curves' either - in some cases including notch filters to help it sound better in typical untreated rooms)....

If you've got a high-end system (or studio monitors) and the right listening room & treatments, you'll almost certainly prefer listening to a master.. there's a lot more 'musical truth' in a good master.

If you have a low-mid end system, you'll probably prefer the retail/consumer mix though - a lot of effort was put into that to get the most out of your rig & room.

[snorkelador]

Selling high resolution audio recordings is just another trick to sell people the same stuff again. When CDs came out, the music industry had kind of a revival, because people went and bought the stuff they often already had on records again on CD. All they had to do was use the old recodings, maybe print digital re-master on the cover, indicating a more modern (over)use of downward compression, and distribute the "new" old products. Now there's a chance to do the same again with so called his res recordings. Truth is, that unless there is a different master done, you won't hear any difference. 24bit to 16bit wordlength aka bitdepth brings you great benefits when recording, because you have a bigger headroom, so you can record at lower levels to avoid clipping and still have a better signal to noise ratio. For playback it's absolutely irrelevant. All you get it more amplitude levels nothing else. Higher sample rates are even more meaningless. Unless you want to do some fancy things like extreme audiostretching with a recording, there is no benefit going beyond 44.1kHz, which captures any frequency up to 22,050 Hz just as well as a higher sample rate. This is already higher than the frequency range of the human ear and still has wiggle room for resonance in the filter, which cut out any frequencies beyond human hearing range, to actually protect speakers and headphones, which may get damaged by such high frequencies. Bitrate in MP3 or other compressed formats is a completly different topic though. There the old mantra of "the higher the better" is much more true.

Before jumping on the high res bandwagon, you may want to check out this: https://wiki.xiph.org/Videos/Digital_Show_and_Tell

[KittenKong]

Have you ever heard the difference between a CD and a SA-CD? It is generally staggering (assuming a good quality source).

The difference between the SA-CD tracks and the CD tracks on a hybrid SA-CD is also very noticeable to me.

[snorkelador]

Whatever that noticible difference may be, it's got nothing to do with the bitdepth and sampling rate of the audio file.

[KittenKong]

Whatever that noticible difference may be, it's got nothing to do with the bitdepth and sampling rate of the audio file.

So you can't hear the difference between a 320kbs mp3 file and a 128kbs mp3 file either? That's a shame. I'm glad I can hear the difference between those, and between CDs and SA-CDs.

[seedy]

Whatever happened with Neil Young and his Pono music ???

Not heard anything in a coons age.

[CarlBkk]

In the blind tests and informal audiophile tests most people cannot tell the difference between hi res and 320 bit mp3 recordings. It's when you get low mp3 bit rates it gets easily audible on decent systems. Depends how revealing they are.

Always check Www.hdtracks.com for hi res and I use Www.junodownloads.com for hi res electronic and mainstream.

[IMHO]

Whatever that noticible difference may be, it's got nothing to do with the bitdepth and sampling rate of the audio file.

So you can't hear the difference between a 320kbs mp3 file and a 128kbs mp3 file either? That's a shame. I'm glad I can hear the difference between those, and between CDs and SA-CDs.

Now we're talking about something else though..bit-rate (kilobits per second), which is not to be confused with sampling-rate (kHz) and bit-depth (bits), which is what we're discussing so far.

Bit depth determines the maximum dynamic range (and therefore Signal-to-Noise ratio) of an audio recording - 16 bit PCM is used by CD, DVD and Bluray with a max SNR of 96dB, 20 bit PCM is used by DVD, Bluray with a max SNR of 120dB, 24 bit is used by SACD, DVD and Bluray with a max SNR of 144dB , and some recording studios use all the way up to 32 bits (max SNR=192dB).

Lossy audio formats like MP3 don't use the concept of bit depth at all.

Sampling rate determines the maximum top-end range of frequency response of an audio recording. CD uses 44.1KHz which means the highest frequency it can record is 22.05kHz (well above the range of human hearing). Higher sampling rates simply increase that range, and it's hotly debated as to whether any actual perceivable difference can be associated with it. Generally speaking, recordings with higher sampling rate also have higher bit depths, and the latter is probably behind the audible improvements heard.

In PCM audio, bit depth and sampling rate both determine the bit rate (kbps).

In compressed audio like MP3, the bit rate is determined by the compression algorithm used, the effective bit depth varies wildly, and the sampling rate also varies wildly, but also has changes to the bottom and top-end (unlike PCM which always ranges down to 1Hz).

Short version: A comparison between 128kbps and 320kbps MP3 audio, in absolutely no way translates to a comparison between 16bit/44.1kHz PCM and 24bit/96KHz PCM (or any other bit-rate/sampling-rate combination).

Indeed, it's entirely possible to encode a sound (albeit not much more complex than a single tone) as a 128kbps MP3 that would be literally indistinguishable from the same sound encoded at 24bit/96KHz PCM... it all depends on just how many bits are actually needed to record the original sound - and there's a massive amount of variables that play into that

[KittenKong]

In PCM audio, bit depth and sampling rate both determine the bit rate (kbps).

In compressed audio like MP3, the bit rate is determined by the compression algorithm used, the effective bit depth varies wildly, and the sampling rate also varies wildly, but also has changes to the bottom and top-end (unlike PCM which always ranges down to 1Hz).

Short version: A comparison between 128kbps and 320kbps MP3 audio, in absolutely no way translates to a comparison between 16bit/44.1kHz PCM and 24bit/96KHz PCM (or any other bit-rate/sampling-rate combination).

My point was that there are people who maintain that one cant hear the difference between 128kbs mp3 and 320kbs mp3 also. I can, and I can also hear the difference between CD and SA-CD. Now exactly which part of the SA-CD signal is the extra part I can hear may be up for discussion, but at the end of the day it doesn't make much difference to the question of whether I can hear it or not.

Indeed, it's entirely possible to encode a sound (albeit not much more complex than a single tone) as a 128kbps MP3 that would be literally indistinguishable from the same sound encoded at 24bit/96KHz PCM... it all depends on just how many bits are actually needed to record the original sound - and there's a massive amount of variables that play into that

Certainly, but I dont think I will ever be spending much time listening to sine waves that sound the same regardless of whether they are encoded as mp3 or PCM. At least not until I lose my marbles completely. The sort of things I listen to have a lot more complexity to them.

[IMHO]

In PCM audio, bit depth and sampling rate both determine the bit rate (kbps).

In compressed audio like MP3, the bit rate is determined by the compression algorithm used, the effective bit depth varies wildly, and the sampling rate also varies wildly, but also has changes to the bottom and top-end (unlike PCM which always ranges down to 1Hz).

Short version: A comparison between 128kbps and 320kbps MP3 audio, in absolutely no way translates to a comparison between 16bit/44.1kHz PCM and 24bit/96KHz PCM (or any other bit-rate/sampling-rate combination).

My point was that there are people who maintain that one cant hear the difference between 128kbs mp3 and 320kbs mp3 also. I can, and I can also hear the difference between CD and SA-CD. Now exactly which part of the SA-CD signal is the extra part I can hear may be up for discussion, but at the end of the day it doesn't make much difference to the question of whether I can hear it or not.

Indeed, it's entirely possible to encode a sound (albeit not much more complex than a single tone) as a 128kbps MP3 that would be literally indistinguishable from the same sound encoded at 24bit/96KHz PCM... it all depends on just how many bits are actually needed to record the original sound - and there's a massive amount of variables that play into that

Certainly, but I dont think I will ever be spending much time listening to sine waves that sound the same regardless of whether they are encoded as mp3 or PCM. At least not until I lose my marbles completely. The sort of things I listen to have a lot more complexity to them.

I don't see anyone here claiming that they can't hear the difference between 128kbps and 320kbps MP3's - in fact no-one was talking about MP3's - except for you attempting to put words into someone else's mouth, so you had extra ammo to attack them

Maybe I should have just responded with: "Comparing MP3's to what we're talking about is dumb" and left it at that, the rest of it wasn't targeted at you, just those who don't understand the difference, but want to

The fact is, whatever differences (or not) you can hear in SACD vs CD is what the recording engineer wanted you to hear. Some might have noticeable differences, others will not. The technology alone doesn't guarantee a different/better listening experience.

[snorkelador]

Whatever that noticible difference may be, it's got nothing to do with the bitdepth and sampling rate of the audio file.

So you can't hear the difference between a 320kbs mp3 file and a 128kbs mp3 file either? That's a shame. I'm glad I can hear the difference between those, and between CDs and SA-CDs.

I actually do hear a difference between 320kb/s and 128kb/s mp3 files. I wonder how you got the idea I could not? However between 320kb/s CBR and 0 - 260 kb/s VBR bitrates, compressed with the same codec, I do admit that I kinda struggle to tell a defference.

As I said before: "Bitrate in MP3 or other compressed formats is a completly different topic though. There the old mantra of "the higher the better" is much more true.".

[KittenKong]

I don't see anyone here claiming that they can't hear the difference between 128kbps and 320kbps MP3's - in fact no-one was talking about MP3's - except for you attempting to put words into someone else's mouth, so you had extra ammo to attack them

I didnt attempt to put words into anyone's mouth, nor did I need to. I asked a question using words of my own. If you cant see that, well ....

Maybe I should have just responded with: "Comparing MP3's to what we're talking about is dumb" and left it at that, the rest of it wasn't targeted at you, just those who don't understand the difference, but want to

Ho hum.

The fact is, whatever differences (or not) you can hear in SACD vs CD is what the recording engineer wanted you to hear. Some might have noticeable differences, others will not. The technology alone doesn't guarantee a different/better listening experience.

Nor did I say it does. But regardless of what the recording engineer wants, you cant fit a SA-CD quart into a CD pint pot.

[astral]

MP3 is a compressed lossy format and any real idea of High Resolution is lost.

Background noise like tape hiss plays havoc with compression because the encoder

does not have the intelligence to distinguish between random high frequency sound

and quiet high pitch music.

Audience applause confuses a lossy compressor too. So can a drum solo with the

very rapid transients of a crisp rudiments roll, too fast for the coder to process.

A cymbal splash becomes a high frequency mess.

So lets keep to the original post about Hi Res Audio.

[snorkelador]

What IMHO and I were trying to convey had nothing to do with compressed sound files, not even lossless ones, but with the reasons why "Hi Res Audio" does not make a difference for playback. You can take the content of those super audio CDs, DVDs and whatnot, convert them to 16bit / 44.1Khz and even experts who claim they hear the difference, will fail to prove it in an ABX test. The link I posted is very interesting btw.

I do understand though that people who swear by this stuff, having invested some time and money in this hype, may not want to hear that at all...

[IMHO]

What IMHO and I were trying to convey had nothing to do with compressed sound files, not even lossless ones, but with the reasons why "Hi Res Audio" does not make a difference for playback. You can take the content of those super audio CDs, DVDs and whatnot, convert them to 16bit / 44.1Khz and even experts who claim they hear the difference, will fail to prove it in an ABX test. The link I posted is very interesting btw.

I do understand though that people who swear by this stuff, having invested some time and money in this hype, may not want to hear that at all...

Indeed, while some people swear by tweeters that extend well out of the audio spectrum, in my last hearing tests I flunked out at 16kHz (age 35), and then look at SNR - unless you're in a dead silent environment, you're not really hearing detailed sounds until they hit around 20dB+, so even with "just" 96dB dynamic range, you're talking about some awfully loud sounds at the top end of the available range

If your system can comfortably do 140dB, and you can stand sounds that loud on peaks, and the recording engineer didn't use any compression, and they found a way to use the full range available, the yes, you might hear the difference between 16 and 24bit recordings No-one actually mixes tracks that way though...

What they can do is use less compression, mix using a wider dynamic range and make an SACD recording sound different to a CD recording. It's highly unlikely they actually needed >16bits or >44.1KHz to achieve their aim though - which is why those ABX tests you speak about result they way they do

Bottom line is, high bit rates/sample rates make sense when *recording* so you can feel sure you've captured as much signal as possible. Once those sounds get compressed, gated, EQ'd, DSP'd and mixed into the resulting track though, resolution needs are dropped.

To be clear - I'm not saying that SACD and CD recordings sound the same. I am saying that the extra bits and samples in SACD weren't actually required to achieve the different result (if it exists). I assume snorkelador is saying the same