High resolution audio. The science, or lack of...?

[AlmaataKZ]

I never said that only an active system would do. Notice that I said: "the same could be said for any underpowered active systems too".

Buy to have the dynamic range capibilities to go loud enough to make full use of what 16 bit audio can offer require an amplifier with lots of power.

So, once again, explain why a passive system, with a really good 80w amplifier and quality speakers, is unable to playback high-res audio to a level that is discernible to 16/44, and only a 100w+ system is.

The 100 Watts thing is a bit of nonsense from elsewhere...however Steve is correct in saying you will be unable to appreciate a higher DR with a weedy amp.

http://www.crownaudio.com/elect-pwr-req.htm

Put the figures in yourself...

Let's say you have a really well recorded bit of HD music with a 30 dB dynamic range. Your "normal/high" listening level is 85 dB which is loud but not blowing the windows out loud...

If you say you want the middle loudness to be at 85 and allow for peaks of around 100 then you need a 15 dB headroom and preferably a little higher as you risk clipping the occaisional snare hit (or whatever), but we'll stick with 15 for now.

Let's say you have good, sensitive 89 dB at 1m speakers and you are sat 3m away...

In this case you need the amplifier to be able to produce 113 Watts.

You make the speakers some expensive 84 dB efficiency ones and it's over 300.

Of course some good amps that are rated 50, 60 WPC will rise to 100, 200 for peaks, and in those cases you'll be fine...But don't try to use a Nad 3020 for parties...

Saying that, people at parties rarely care about quality, so the occaisional bit of clipping won't matter.

It's all comletely irrelevant though. A 30 dB dynamic range is unusual to the point of almost non-existant. If you used the whole dynamic range of a CD and played at a level where you could hear the lowest levels, the loudest levels would pretty much instantly deafen you.

A quiet room is at around 35 dB. A CD has around 96 dB of DR. So the peaks would be at around 130 dB...Eardrum destroying levels...

good posting, frog. Hi rez audio without knowing what one is trying to achieve is pointless. And once one knows, it is ... Pointless.

 

[AlmaataKZ]

...There are other considerations to digital audio recording/reproduction than the Nyquist sampling theorem...

A 44.1kHz sample rate can accurately reproduce any wave upto 22.05kHz and 16bit audio can reproduce the full dynamic range that is audible to humans. What other considerations are necessary?

(A genuine question. Not just being awkward. )

high performance transducers (genuine answer!)

 

[NHL]

I never said that only an active system would do. Notice that I said: "the same could be said for any underpowered active systems too".

Buy to have the dynamic range capibilities to go loud enough to make full use of what 16 bit audio can offer require an amplifier with lots of power.

So, once again, explain why a passive system, with a really good 80w amplifier and quality speakers, is unable to playback high-res audio to a level that is discernible to 16/44, and only a 100w+ system is.

The 100 Watts thing is a bit of nonsense from elsewhere...however Steve is correct in saying you will be unable to appreciate a higher DR with a weedy amp.

http://www.crownaudio.com/elect-pwr-req.htm

Put the figures in yourself...

Let's say you have a really well recorded bit of HD music with a 30 dB dynamic range. Your "normal/high" listening level is 85 dB which is loud but not blowing the windows out loud...

If you say you want the middle loudness to be at 85 and allow for peaks of around 100 then you need a 15 dB headroom and preferably a little higher as you risk clipping the occaisional snare hit (or whatever), but we'll stick with 15 for now.

Let's say you have good, sensitive 89 dB at 1m speakers and you are sat 3m away...

In this case you need the amplifier to be able to produce 113 Watts.

You make the speakers some expensive 84 dB efficiency ones and it's over 300.

Of course some good amps that are rated 50, 60 WPC will rise to 100, 200 for peaks, and in those cases you'll be fine...But don't try to use a Nad 3020 for parties...

Saying that, people at parties rarely care about quality, so the occaisional bit of clipping won't matter.

It's all comletely irrelevant though. A 30 dB dynamic range is unusual to the point of almost non-existant. If you used the whole dynamic range of a CD and played at a level where you could hear the lowest levels, the loudest levels would pretty much instantly deafen you.

A quiet room is at around 35 dB. A CD has around 96 dB of DR. So the peaks would be at around 130 dB...Eardrum destroying levels...

good posting, frog. Hi rez audio without knowing what one is trying to achieve is pointless. And once one knows, it is ... Pointless.

and yet, in a not so far distant future, everyone will sit with their new DSD compatible DAC HW. My point is that marketing is a stronger force than science in this case.

 

[AlmaataKZ]

I never said that only an active system would do. Notice that I said: "the same could be said for any underpowered active systems too".

Buy to have the dynamic range capibilities to go loud enough to make full use of what 16 bit audio can offer require an amplifier with lots of power.

So, once again, explain why a passive system, with a really good 80w amplifier and quality speakers, is unable to playback high-res audio to a level that is discernible to 16/44, and only a 100w+ system is.

The 100 Watts thing is a bit of nonsense from elsewhere...however Steve is correct in saying you will be unable to appreciate a higher DR with a weedy amp.

http://www.crownaudio.com/elect-pwr-req.htm

Put the figures in yourself...

Let's say you have a really well recorded bit of HD music with a 30 dB dynamic range. Your "normal/high" listening level is 85 dB which is loud but not blowing the windows out loud...

If you say you want the middle loudness to be at 85 and allow for peaks of around 100 then you need a 15 dB headroom and preferably a little higher as you risk clipping the occaisional snare hit (or whatever), but we'll stick with 15 for now.

Let's say you have good, sensitive 89 dB at 1m speakers and you are sat 3m away...

In this case you need the amplifier to be able to produce 113 Watts.

You make the speakers some expensive 84 dB efficiency ones and it's over 300.

Of course some good amps that are rated 50, 60 WPC will rise to 100, 200 for peaks, and in those cases you'll be fine...But don't try to use a Nad 3020 for parties...

Saying that, people at parties rarely care about quality, so the occaisional bit of clipping won't matter.

It's all comletely irrelevant though. A 30 dB dynamic range is unusual to the point of almost non-existant. If you used the whole dynamic range of a CD and played at a level where you could hear the lowest levels, the loudest levels would pretty much instantly deafen you.

A quiet room is at around 35 dB. A CD has around 96 dB of DR. So the peaks would be at around 130 dB...Eardrum destroying levels...

good posting, frog. Hi rez audio without knowing what one is trying to achieve is pointless. And once one knows, it is ... Pointless.

and yet, in a not so far distant future, everyone will sit with their new DSD compatible DAC HW.

marketing is a powerful thing, and, as good music mastering, it is done by intelligent people. So both achieve their intended results.

 

[PEAYEL]

I have read this thread with interest. As a Sound Engineer you have all missed the most important link in the chain.... The microphone. As far as I am aware, no matter how much you spend, there are no microphones that you can put in front of a source, ie piano, violin, voice, guitar, that will record beyond the range of human hearing. Even if they can, they are usually rolled off steeply after the 20khz point. Microphones have different voicings, I agree, which gives a different tone, even to the same source.

However, if it is not recorded above 20khz with the very first link in the chain, then how on earth can you hear it later on. No matter how much how much one spends on kit.

I recently worked in a studio where they were mixing down on a pair of PMC BB5 XBD actives. I think that the installation cost in the region of £45k for the speaker set up alone. Accurate no doubt but these monsters would not look good or sound good in your average house. Whilst there I went through their microphone selection, I found one of my favourites, the Neumann M150 Tube Omni, this costs £4k retail, and is superb for recording most sources. It has a dynamic range of 119dB and frequency response of 20hz to 20 KHz. It doesn't record beyond this, thus it cannot transfer information to the recording medium in excess of this. Consequently, you will not have anything beyond that to listen to. Add this to the aforementioned proven Nyquist theory, then in my honest opinion there is no point to HD beyond the maximum 48 kHz CD rate. I can see the reasoning behind 24 bit against 16 bit, however, unless you have the hearing of a child, or dog, then again there is no point.

I simply prefer to buy kit that excites me and makes me smile, because it makes me happy.

 

[altruistic.lemon]

The 100 Watts thing is a bit of nonsense from elsewhere...however Steve is correct in saying you will be unable to appreciate a higher DR with a weedy amp.

http://www.crownaudio.com/elect-pwr-req.htm

Put the figures in yourself...

Let's say you have a really well recorded bit of HD music with a 30 dB dynamic range. Your "normal/high" listening level is 85 dB which is loud but not blowing the windows out loud...

If you say you want the middle loudness to be at 85 and allow for peaks of around 100 then you need a 15 dB headroom and preferably a little higher as you risk clipping the occaisional snare hit (or whatever), but we'll stick with 15 for now.

Let's say you have good, sensitive 89 dB at 1m speakers and you are sat 3m away...

In this case you need the amplifier to be able to produce 113 Watts.

You make the speakers some expensive 84 dB efficiency ones and it's over 300.

Of course some good amps that are rated 50, 60 WPC will rise to 100, 200 for peaks, and in those cases you'll be fine...But don't try to use a Nad 3020 for parties...

Saying that, people at parties rarely care about quality, so the occaisional bit of clipping won't matter.

It's all comletely irrelevant though. A 30 dB dynamic range is unusual to the point of almost non-existant. If you used the whole dynamic range of a CD and played at a level where you could hear the lowest levels, the loudest levels would pretty much instantly deafen you.

A quiet room is at around 35 dB. A CD has around 96 dB of DR. So the peaks would be at around 130 dB...Eardrum destroying levels...

You're correct (!). You want an amp that can cope with short peaks, correct, and many, notably NAD, in fact, do. It's the reason why a 50w Naim amp sounds so good with classical -and it's mainly classical - because short term peaks are around the 100w mark. Saw a set of figures somewere that tested peak power, and the only one of the 50W amps that topped out under 100W - 83W if I remember correctly - was the Brio R.

Therefore, a 50w amp isn't weedy at all, in fact it can be just fine.

Also, unless you listen to a lot of classical, a 25W amp may also be good. Also, very few speakers sit at 84db. Most are around the 87db mark. Anyway the most limiting factor isn't the wattage, it's the neighbours.

 

[matthewpiano]

I have read this thread with interest. As a Sound Engineer you have all missed the most important link in the chain.... The microphone. As far as I am aware, no matter how much you spend, there are no microphones that you can put in front of a source, ie piano, violin, voice, guitar, that will record beyond the range of human hearing. Even if they can, they are usually rolled off steeply after the 20khz point. Microphones have different voicings, I agree, which gives a different tone, even to the same source.

However, if it is not recorded above 20khz with the very first link in the chain, then how on earth can you hear it later on. No matter how much how much one spends on kit.

I recently worked in a studio where they were mixing down on a pair of PMC BB5 XBD actives. I think that the installation cost in the region of £45k for the speaker set up alone. Accurate no doubt but these monsters would not look good or sound good in your average house. Whilst there I went through their microphone selection, I found one of my favourites, the Neumann M150 Tube Omni, this costs £4k retail, and is superb for recording most sources. It has a dynamic range of 119dB and frequency response of 20hz to 20 KHz. It doesn't record beyond this, thus it cannot transfer information to the recording medium in excess of this. Consequently, you will not have anything beyond that to listen to. Add this to the aforementioned proven Nyquist theory, then in my honest opinion there is no point to HD beyond the maximum 48 kHz CD rate. I can see the reasoning behind 24 bit against 16 bit, however, unless you have the hearing of a child, or dog, then again there is no point.

I simply prefer to buy kit that excites me and makes me smile, because it makes me happy.

I really like this post. You can't add what isn't there in the first place. As for your last line I think it defines what a system should be about IMO - getting you excited about the music, allowing you to engage with the music.

:cheers:

 

[JamesMellor]

" Anyway the most limiting factor isn't the wattage, it's the neighbours. "

Tell me about it ! , alot of Friday nights I just have to keep turning it up so I can't hear them banging on the wall , some people .

James

 

[manicm]

I have read this thread with interest. As a Sound Engineer you have all missed the most important link in the chain.... The microphone. As far as I am aware, no matter how much you spend, there are no microphones that you can put in front of a source, ie piano, violin, voice, guitar, that will record beyond the range of human hearing. Even if they can, they are usually rolled off steeply after the 20khz point. Microphones have different voicings, I agree, which gives a different tone, even to the same source.

However, if it is not recorded above 20khz with the very first link in the chain, then how on earth can you hear it later on. No matter how much how much one spends on kit.

I recently worked in a studio where they were mixing down on a pair of PMC BB5 XBD actives. I think that the installation cost in the region of £45k for the speaker set up alone. Accurate no doubt but these monsters would not look good or sound good in your average house. Whilst there I went through their microphone selection, I found one of my favourites, the Neumann M150 Tube Omni, this costs £4k retail, and is superb for recording most sources. It has a dynamic range of 119dB and frequency response of 20hz to 20 KHz. It doesn't record beyond this, thus it cannot transfer information to the recording medium in excess of this. Consequently, you will not have anything beyond that to listen to. Add this to the aforementioned proven Nyquist theory, then in my honest opinion there is no point to HD beyond the maximum 48 kHz CD rate. I can see the reasoning behind 24 bit against 16 bit, however, unless you have the hearing of a child, or dog, then again there is no point.

I simply prefer to buy kit that excites me and makes me smile, because it makes me happy.

Here's a link to a microphone released in 1998.

http://recordinghacks.com/microphones/Earthworks/QTC40

 

[Anonymous]

science is irrelevant

This thread is irrelevant, including most of the posts on it, to be honest.

 

[davedotco]

If we're a tiny bit sensible and limit the maximum volume to 120 dbs, that gives us a range limit of human hearing of 100 to 120 dbs for people with non-damaged hearing. That's more than 16/44.1 can provide full stop. And it's way more than 16/44.1 can provide without noticeable amounts of distortion.

Clearly there's more to digital audio than The Sampling Theorem (which assumes exact sampling) so there's no point trying to debate that here. The important question is whether you can actually hear the distortion.

It seems to me the best way to determine that would be to insert a Red Book ADA "bottleneck" into an analogue replay chain and compare it with the original in a properly controlled ABX test. I suspect the result would be negative.

This has been done many many times over the decades.

I can recall a demonstration back in the early 1980s where a decent analog system (Studio tape recorder) was set up and four sony PCM F1 digital processors were placed in the signal path.

The PCM-F1 was the (pro) industry standard in those days and pretty unsophisticated by modern standards. it was a stereo device with both A to D and D to A circuits in the same package. It was set up so that each unit took an analogue signal, converted it to 16/44.1 digital and then back again to analogue, with 4 PCM F1 units in the chain this gave 8 processes, 4 A to D and 4 D to A.

Even with a decent quality studio master and a quality playback system, no one was able to tell when the digital processors were in line or not. and this is with 30 year old technology!

Sadly, although this was written up at the time, I can not find any references to it, so I refer you to this instead.

http://www.bostonaudiosociety.org/bas_speaker/abx_testing2.htm

This is both enlightening and most amusing.......

 

[davedotco]

Just as a point of interest.......

Would anyone like to guess at the number of bits that a decent digital playback system (transport/computer/streamer and Dac) might be capable of resolving in a home environment......... :?

 

[altruistic.lemon]

Ooh ,goodie, I love guessing games! What's the prize?

 

[steve_1979]

A 44.1kHz sample rate can accurately reproduce any wave upto 22.05kHz and 16bit audio can reproduce the full dynamic range that is audible to humans. What other considerations are necessary?

(A genuine question. Not just being awkward. )

high performance transducers (genuine answer!)

True dat.

 

[steve_1979]

.... underpowered 30-100 watt amplifiers together with power sapping passive speakers?

And there we have the nub of it. The elephant in the room.

(And a little odd from someone using "power sapping passives".)

This is an interesting point that you make here Chebby which I was thinking about while I was out today.

My Neutron 5 system with its 300 watts of amplification has considerably more dynamic range than most typical hifi systems but I doubt that even this would be enough to make full use of the 35dB to 130dB dynamic range capabilities that 16/44.1 offers.

The only reason that I mentioned passives (which I quickly regretted doing) is because they are what most people use and watt for watt they are less efficient than actives and so they tend to have less dynamic range.

 

[Crossie]

Please read my earlier response. 16/44.1 will not satisfy conditions to invoke Nyquist Shannon Therorem (NST) as the sampling is inaccurate ie. measured to the nearest bit not to full precision that is required for the NST to be applied.

Sorry.

 

[Crossie]

Continued,

Cd quality does gaurantee to reproduce the exact input waveform.

 

[steve_1979]

So, once again, explain why a passive system, with a really good 80w amplifier and quality speakers, is unable to playback high-res audio to a level that is discernible to 16/44, and only a 100w+ system is.

16/44.1 has a dynamic range that can go from being as quiet as a silent domestic room (35dB) all the way up to being loud enough to sound uncomfortable and damage your hearing (130dB). To be able to hear this full dynamic range you would need a system that can go loud enough to do that. An 80 watt hifi amp just isn't powerful enough to play at those levels.

So the point that I was originally making is that 16 bit audio already has more dynamic range than most typical hifi systems are capable of reproducing or is comfortable to listen to. So why would you need 24bit audio to give you more than that?

 

[chebby]

My Neutron 5 system with its 300 watts of amplification has considerably more dynamic range than most typical hifi systems...

Again a bit disingenuous. You make it read like you have a 300 Watt amp.

It's a 100 Watts per channel system (with a 100W sub).

People don't go around calling their 75 Watts per channel amps ... '150 Watt amps'.

Therefore (along with it's 'power sapping' passives) it just qualifies for your description of one of those audiophile systems with their...

"... underpowered 30-100 watt amplifiers together with power sapping passive speakers"

It also comes from a small, UK, specialist, high-quality, hi-fi manufacturer. So qualifies (again) as an 'audiophile system'. (AVI stuff is not exactly in the 'bucket' list at Richer Sounds!)

Face it, you own an audiophile system (Neutron 5.2.1 systems were about £1250 when new and that's without any source.)

 

[NHL]

Please read my earlier response. 16/44.1 will not satisfy conditions to invoke Nyquist Shannon Therorem (NST) as the sampling is inaccurate ie. measured to the nearest bit not to full precision that is required for the NST to be applied.

Sorry.

this will only manifest itself as random noice, nothing else.

 

[Crossie]

Agreed but a higher bit rate will result in less random noise.

 

[steve_1979]

My Neutron 5 system with its 300 watts of amplification has considerably more dynamic range than most typical hifi systems...

Again a bit disingenuous. You make it read like you have a 300 Watt amp.

It's a 100 Watts per channel system (with a 100W sub).

People don't go around calling their 75 Watts per channel amps ... '150 Watt amps'.

Therefore (along with it's 'power sapping' passives) it just qualifies for your description of one of those audiophile systems with their...

"... underpowered 30-100 watt amplifiers together with power sapping passive speakers"

It also comes from a small, UK, specialist, high-quality, hi-fi manufacturer. So qualifies (again) as an 'audiophile system'. (AVI stuff is not exactly in the 'bucket' list at Richer Sounds!)

Face it, you own an audiophile system (Neutron 5.2.1 systems were about £1250 when new and that's without any source.)

Correct on all accounts.

And like I said it doesn't have the dynamic range capabilities to make full use of what 16/44.1 can offer.

 

[lindsayt]

So, once again, explain why a passive system, with a really good 80w amplifier and quality speakers, is unable to playback high-res audio to a level that is discernible to 16/44, and only a 100w+ system is.

16/44.1 has a dynamic range that can go from being as quiet as a silent domestic room (35dB) all the way up to being loud enough to sound uncomfortable and damage your hearing (130dB). To be able to hear this full dynamic range you would need a system that can go loud enough to do that. An 80 watt hifi amp just isn't powerful enough to play at those levels.

So the point that I was originally making is that 16 bit audio already has more dynamic range than most typical hifi systems are capable of reproducing or is comfortable to listen to. So why would you need 24bit audio to give you more than that?

I don''t know of any domestic hi-fi system that can go up to 130 dbs at the listening postion - which would require 135 to 140 or more dbs at 1 metre from the speakers for most rooms.

I don't know of any domestic active sytems that can play at 120 dbs all day long at 1 metre and therefore 110 dbs at my listening position. I do know of a passive domestic system that can. And it does it with 80 watts.

Does anyone know of any commercially released CD's that have a dynamic range of more than 40dbs? Possibly one for another thread, but what's the most dynamic CD that everyone owns here, and how many dbs difference is there between the peaks and the quietest bits where music is playing (between track silence doesn't count)?

 

[lindsayt]

So, once again, explain why a passive system, with a really good 80w amplifier and quality speakers, is unable to playback high-res audio to a level that is discernible to 16/44, and only a 100w+ system is.

16/44.1 has a dynamic range that can go from being as quiet as a silent domestic room (35dB) all the way up to being loud enough to sound uncomfortable and damage your hearing (130dB). To be able to hear this full dynamic range you would need a system that can go loud enough to do that. An 80 watt hifi amp just isn't powerful enough to play at those levels.

So the point that I was originally making is that 16 bit audio already has more dynamic range than most typical hifi systems are capable of reproducing or is comfortable to listen to. So why would you need 24bit audio to give you more than that?

I don''t know of any domestic hi-fi system that can go up to 130 dbs at the listening postion - which would require 135 to 140 or more dbs at 1 metre from the speakers for most rooms.

I don't know of any domestic active sytems that can play at 120 dbs all day long at 1 metre and therefore 110 dbs at my listening position. I do know of a passive domestic system that can. And it does it with 80 watts.

Does anyone know of any commercially released CD's that have a dynamic range of more than 40dbs? Possibly one for another thread, but what's the most dynamic CD that everyone owns here, and how many dbs difference is there between the peaks and the quietest bits where music is playing (between track silence doesn't count)?

 

[steve_1979]

I don''t know of any domestic hi-fi system that can go up to 130 dbs at the listening postion - which would require 135 to 140 or more dbs at 1 metre from the speakers for most rooms.

I don't know of any domestic active sytems that can play at 120 dbs all day long at 1 metre and therefore 110 dbs at my listening position. I do know of a passive domestic system that can. And it does it with 80 watts.

Genelec's big, 2 x 390 watt, three-way 8260A speakers when partnered with one of their huge dining table sized subwoofers can almost do it (the 8260A's tweeter and midrange drivers go much louder than the built in 10" bass driver so they need to be partnered with a separate subwoofer to hear them at maximum volume).

Does anyone know of any commercially released CD's that have a dynamic range of more than 40dbs? Possibly one for another thread, but what's the most dynamic CD that everyone owns here, and how many dbs difference is there between the peaks and the quietest bits where music is playing (between track silence doesn't count)?

Exactly! If music only has a maximum dynamic range of around 40dB* why would you need more then the 96dB range that 16/44.1 offers?

* Out of interest can anyone confirm what the maximum dynamic range that music uses actually is?