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What does "lower noise floor" actually mean


sdolezalek
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I often read equipment reviews that comment about a particular piece of equipment having a lower noise floor, or equipment that provides "blacker blacks" to use terminology perhaps better suited to televisions. Although I understand the concept, I'm not clear whether that is actually what people are hearing.

 

If it were true then it would seem you could measure the base noise level of your sound room with everything turned off, turn on all the equipment and then measure to what extent the "silent" passages exhibited a noise floor identical to that with the equipment turned off. My guess is that unless you have a real problem the noise floor with equipment on but playing silence and that with it turned off will measure as "same."

 

So what are people referring to when they make the "lower noise floor" comment?

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I often read equipment reviews that comment about a particular piece of equipment having a lower noise floor, or equipment that provides "blacker blacks" to use terminology perhaps better suited to televisions. Although I understand the concept, I'm not clear whether that is actually what people are hearing.

 

If it were true then it would seem you could measure the base noise level of your sound room with everything turned off, turn on all the equipment and then measure to what extent the "silent" passages exhibited a noise floor identical to that with the equipment turned off. My guess is that unless you have a real problem the noise floor with equipment on but playing silence and that with it turned off will measure as "same."

 

So what are people referring to when they make the "lower noise floor" comment?

 

 

A noise floor is the threshold below which no audio intelligence can be heard. In other words, at any audio system's (either record or playback) noise floor, the background noise of that system becomes just as loud as the signal giving a signal-to-noise ratio of 0. so any signal that's quieter than that floor is not as loud as the noise added to it making it difficult to impossible to transmit or record that signal (in other words, you will have a negative signal-to-noise ratio or a positive noise-to-signal ratio!). Some examples: Pristine vinyl has a signal-to-noise ratio (SNR) of about 55-58 dB. Analog reel-to-reel tape is about 70 dB. CD (16 bit digital) has an SNR of about 98 dB, 24-bit recordings have a theoretical SNR of 144 dB, but since even the quietest electronics have a maximum SNR of around 127 dB, this 144 dB figure is never actually achieved because nothing else in the recording or the playback chain can come anywhere close to being that quiet. BTW, the human ear's threshold of hearing is usually given as -115 to -117 db, you can see that the best audio electronics and recording specifications are so quiet (being 10 dB below any human's ability to hear anything) that the human ear cannot hear their noise floor. For these and other practical considerations these figures for high-resolution recordings and state-of-the-art electronics are rarely if ever achieved. Basically, for all practical purposes, CD's 98 dB or better is considered noiseless. I hope this helps.

George

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A noise floor is the threshold below which no audio intelligence can be heard. ... For these and other practical considerations these figures for high-resolution recordings and state-of-the-art electronics are rarely if ever achieved. Basically, for all practical purposes, CD's 98 dB or better is considered noiseless. I hope this helps.

 

George: Thanks. I knew the technical definition of both noise floor and signal-to-noise ratios. My question was intended to be a bit more practical. On a normal day the background noise in my listening room measures about 23db. Therefore if I was really going to appreciate the full benefit of a 100db SNR piece of equipment, I'd presumably have to listen to my music at greater than 120db.

 

When I'm listening at say 90db, how do my ears actually "hear" the benefit of resolution greater than the difference between the peak sound level (90db) and my room's noise floor of 23db? Great equipment can't make my room "more silent", so what is it really doing that I can hear?

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George: Thanks. I knew the technical definition of both noise floor and signal-to-noise ratios. My question was intended to be a bit more practical. On a normal day the background noise in my listening room measures about 23db. Therefore if I was really going to appreciate the full benefit of a 100db SNR piece of equipment, I'd presumably have to listen to my music at greater than 120db.

 

When I'm listening at say 90db, how do my ears actually "hear" the benefit of resolution greater than the difference between the peak sound level (90db) and my room's noise floor of 23db? Great equipment can't make my room "more silent", so what is it really doing that I can hear?

 

Well depending upon the particulars you can normally hear to some extent 15 to maybe 20 db into a noise floor. The particulars being the character of the noise vs the signal. Harmonic distortion will likely be masked in the noise floor, but a low level primary signal in the noise and with a different character than the noise would perhaps be heard. There is no finely drawn line for all cases.

 

I forget where, someone recently said the very widest dynamic range recordings anyone can find are something short of or near a 90 db range. Wish I remembered where I saw that.

 

In any case, if people reporting the blacker background and lowered noise floor are hearing anything real I doubt it is the actual measured noise. Since good tube gear can sometimes make music seem to explode with more dynamics from a blacker background it might even be compression and barely/nearly audible noise that makes this subjective effect heard.

 

Of course the other subjective report is you get lowered noise with low jitter. I obviously consider that an incredibly tenuous assertion, but many make it.

And always keep in mind: Cognitive biases, like seeing optical illusions are a sign of a normally functioning brain. We all have them, it’s nothing to be ashamed about, but it is something that affects our objective evaluation of reality. 

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George: Thanks. I knew the technical definition of both noise floor and signal-to-noise ratios. My question was intended to be a bit more practical. On a normal day the background noise in my listening room measures about 23db. Therefore if I was really going to appreciate the full benefit of a 100db SNR piece of equipment, I'd presumably have to listen to my music at greater than 120db.

 

When I'm listening at say 90db, how do my ears actually "hear" the benefit of resolution greater than the difference between the peak sound level (90db) and my room's noise floor of 23db? Great equipment can't make my room "more silent", so what is it really doing that I can hear?

 

In my opinion, most serious listeners are able to distinguish between ambient noise, which is ineveitable in most homes, and system noise. I think it's a skill you develop. Despite the fact that my listening environment is far from perfect, a "quieter" system is discernible and appreciated for it's ability to convey more information in a less stressful and confusing manner. I am able to make some modification to my tube amps or some other system component and recognize that the overall noise floor has been lowered. I have an audiophile buddy whose hearing is better than mine and he can easily comment on which tube or circuit or component is "quieter" and thus more enjoyable to listen to.

 

Therefore, I think the pursuit of a lower noise floor in your playback system is worthwhile.

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In my opinion, most serious listeners are able to distinguish between ambient noise, which is ineveitable in most homes, and system noise. I think it's a skill you develop. Despite the fact that my listening environment is far from perfect, a "quieter" system is discernible and appreciated for it's ability to convey more information in a less stressful and confusing manner. I am able to make some modification to my tube amps or some other system component and recognize that the overall noise floor has been lowered. I have an audiophile buddy whose hearing is better than mine and he can easily comment on which tube or circuit or component is "quieter" and thus more enjoyable to listen to.

 

Therefore, I think the pursuit of a lower noise floor in your playback system is worthwhile.

 

+1

More theoretical rubbish above from George.

Both Paul R. and Miska can verify that you are able to hear things below the system noise floor.

This is done in Submarines, where Miska was also an instructor in this area.

 

How a Digital Audio file sounds, or a Digital Video file looks, is governed to a large extent by the Power Supply area. All that Identical Checksums gives is the possibility of REGENERATING the file to close to that of the original file.

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I would add that a system's resolving power depends on different types of noise. A good example is the difference between AC and DC filaments on directly-heated triodes, like the 300B. While AC filaments may create a certain hum which is audible to some extent, they can sound better and "quieter" than DC filaments which, if poorly implemented, can interfere with the music in a more general way.

 

I guess what I'm saying is that there's "noise" and there's "noise". :-) Ambient noise is one thing, while noise that finds its way into the music is another. Generally when people talk about a component being "quieter" they mean that there seems to be less interference with the music itself.

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In my opinion, most serious listeners are able to distinguish between ambient noise, which is ineveitable in most homes, and system noise. I think it's a skill you develop. Despite the fact that my listening environment is far from perfect, a "quieter" system is discernible and appreciated for it's ability to convey more information in a less stressful and confusing manner. I am able to make some modification to my tube amps or some other system component and recognize that the overall noise floor has been lowered. I have an audiophile buddy whose hearing is better than mine and he can easily comment on which tube or circuit or component is "quieter" and thus more enjoyable to listen to.

 

Therefore, I think the pursuit of a lower noise floor in your playback system is worthwhile.

 

+2.

 

It's hard to describe or even put it into words but you hear or "unhear" things, especially if you've done even a little bit of critical listening and have a decent/semi-decent rig.

 

I could hear or "unhear the electrical noise" when I moved source from a nearly $2500 PC to a $35 Raspberry Pi. You can say my jaw hit the floor, or I was breathing expletives, but the difference was huge. It was also my first experience of galvanic isolation... so in a manner of speaking you can say we've all been hearing electrical noise all of our lives and when its removed you can perceive the difference in spades. Of course with the caveat being how much of a resolving system do you have and how much of a critical listener and how well versed are you with the sound of your system, etc.

 

I've a fairly resolving system, and its also somewhat ultra analytical as that's what I prefer - so the difference is more pronounced. I've played with more "warmer" and forgiving speakers like Harbeths with the rest of the chain being the same and the difference was still there, just not so pronounced. This could also be put down to me not being extremely familiar with the Harbeths, but FWIW I did use them for 3 weeks so I did develop a good idea of their sound too.

 

I also have some vintage gear, nearly 40 years and they are extremely unforgiving. Badly mastered CDs are a pain to even listen in them, you'll end up with a headache even before the one album is done. They are extremely revealing or simply amplify what's there. Any bad component gets shown up immediately and in a way its my standard for testing when I introduce or buy new equipment, it gets connected to the vintage rig and I can immediately see and hear the difference. The difference between electrical noise and galvanic isolation in this system is huge, even folks who've not heard my system before can pick on it immediately.

 

Most "modern" systems (other than say Genelecs) are just not so revealing... maybe on purpose or maybe the Bose mantra to sell more stuff by making everything sound good.

 

But I agree with Zack, you'll learn to distinguish between various levels/types of noise, even ambient, from the AC or ventilation, and from your system too.

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Generally when people talk about a component being "quieter" they mean that there seems to be less interference with the music itself.

 

Yes, that's really what I was getting at. Others refer to it as the "veil being lifted" by which I again think they mean that the relative level of noise has been reduced and thus the true signal comes across more clearly.

 

Now as to how to measure these differences and what exactly you would measure??? I'm pretty sure it is more than a pure high SNR.

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I would add that a system's resolving power depends on different types of noise. A good example is the difference between AC and DC filaments on directly-heated triodes, like the 300B. While AC filaments may create a certain hum which is audible to some extent, they can sound better and "quieter" than DC filaments which, if poorly implemented, can interfere with the music in a more general way.

 

I guess what I'm saying is that there's "noise" and there's "noise". :-) Ambient noise is one thing, while noise that finds its way into the music is another. Generally when people talk about a component being "quieter" they mean that there seems to be less interference with the music itself.

 

Another aspect of this is not the noise floor with silence, but the noisefloor with music playing. An example might help.

 

Think of a room with no windows or doors, if you have no light sources in the room, a measure of light intensity is going to be extremely low. Then turn on a flashlight, the beam bounces off the opposite wall, off another wall etc. If you measure the light intensity in an area where the beam is not directly falling, it is now much higher. If the walls are painted white the ratio between the direct beam and non-direct fairly high, if the walls are painted black, it is much less. If the beam is brighter to begin with the non-direct light will also be greater.

 

When most people say the "noisefloor" is lower they are usually talking about a similar situation where the music itself is seeming to generate some low level sound which seems to fill in the space around the instruments. When it is decreased the space around instruments (voices etc) is decreased. Exactly what is happening hear is not really known, since it is very much a perceptual issue.

 

My guess is that the musical signal cause the perceptual system to develop the illusion of the original sound scape, but distortions in the electronics, speakers etc produce low level signals which don't properly correlate with the undistorted signal, thus the perceptual system cannot figure out exactly where to put them, so they wind up filling a large perceptual space between the "instruments". As distortions are decreased this diffuse sound that is not anchored to instruments also decreases, thus the "blacker" space between instruments.

 

This is something that is purely perceptual thus very difficult to measure with test instruments and essentially has nothing to do with actually measured "noise floor" of the signal.

 

John S.

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I think the low level noise sometimes improves perception, and in some situations would be related to this:

 

https://www.researchgate.net/profile/Qian-Jie_Fu/publication/12453895_Human_hearing_enhanced_by_noise/links/55d4b40708ae1e6516636d08.pdf

 

https://en.wikipedia.org/wiki/Stochastic_resonance_%28sensory_neurobiology%29#Audition

 

 

 

Stochastic resonance. Now this is an area of research that isn't all that old. It is likely more specifics will be learned over time as more research occurs.

And always keep in mind: Cognitive biases, like seeing optical illusions are a sign of a normally functioning brain. We all have them, it’s nothing to be ashamed about, but it is something that affects our objective evaluation of reality. 

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I will try and find it , but one of the audio companies once posted a set of files with pings. Each file was progessively "softer" so that the softest ones were -144db down from the volume of the original.

 

You played them back on your system one by one, from loudest to softest. You could see how many db down you could hear them from your normal listening seat at average volume, and this basically gave you the practical noise floor of your equipment/listening environment/ears.

 

You could also turn it up loud and get a few inches away from your speakers. What you could hear with that result would be more or less equal to the "theoretical" noise floor of your system and your ears - what sounds it could reproduce that could be heard over the inherent noise of the system.

 

I don't remember exactly, but in my setup for the first result it I could faintly hear something like -96db down from the base signal, and in the second scenario I could hear (extremely faintly) that my system could audibly reproduce something that was softer, something like -120(?)db down from the base signal. I remember putting my older amp back into the system and the result was not as good - I couldn't hear those weakest signals I heard with my newer amp, meaning the old amp had a higher "noise floor".

 

I was pretty happy with that result, thinking it meant my system wasn't "hiding" too much of what was on recordings from me. Obviously the playback volume has an effect . As does the frequency of the pings, etc. I think that was accounted for in the test files. As I said, I'll try and find the source of the test again and post the download page and explanation of what the files contain.

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I think it's often related to ability to retrieve ultra low level detail and portray 'space between the notes', and unravel individual track layering (I call it 'the edges of the tracks'). E.g. do you hear the composite block of multi-layered backing vocals as a single piece of audio, or do you hear/identify each individual take (track) that was mixed (comp'd) together?

 

Of late, my system seems to excel at this but I couldn't say that's purely down to a very low noise floor. Obviously it's a major contributor, but I suspect that low distortion is also equally at play and the two together portray a 'black background'

 

Just my 2p

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I will try and find it , but one of the audio companies once posted a set of files with pings. Each file was progessively "softer" so that the softest ones were -144db down from the volume of the original.

 

You played them back on your system one by one, from loudest to softest. You could see how many db down you could hear them from your normal listening seat at average volume, and this basically gave you the practical noise floor of your equipment/listening environment/ears.

 

You could also turn it up loud and get a few inches away from your speakers. What you could hear with that result would be more or less equal to the "theoretical" noise floor of your system and your ears - what sounds it could reproduce that could be heard over the inherent noise of the system.

 

I don't remember exactly, but in my setup for the first result it I could faintly hear something like -96db down from the base signal, and in the second scenario I could hear (extremely faintly) that my system could audibly reproduce something that was softer, something like -120(?)db down from the base signal. I remember putting my older amp back into the system and the result was not as good - I couldn't hear those weakest signals I heard with my newer amp, meaning the old amp had a higher "noise floor".

 

I was pretty happy with that result, thinking it meant my system wasn't "hiding" too much of what was on recordings from me. Obviously the playback volume has an effect . As does the frequency of the pings, etc. I think that was accounted for in the test files. As I said, I'll try and find the source of the test again and post the download page and explanation of what the files contain.

 

This site has a nice 16bit/96dB dynamic range test:

 

Online Audible Dynamic Range Sound Test

 

R

"Science draws the wave, poetry fills it with water" Teixeira de Pascoaes

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In my experience, a tonal balance that is tilting upwards from low- to top-end may give an impression of resolution but what it's doing in reality is exaggerating the frequency band where our ear is most sensitive (and is musically just plain "wrong").

 

(Low-level) resolution on the other hand is independent of tonal balance and reveals itself in a better reproduction of instrument and voice timbre nuances as well as a more information on the acoustics of the venue where the recording took place (if this wasn't a quasi-anechoic studio) and longer decay.

There's more detail but it sounds natural and integrated.

 

In my opinion one should use adequately mic'ed recordings of acoustic music in naturally-reverberant spaces (simple, correctly distanced mic setups such as Mario's recordings) for assessment of those qualities.

Close-mic'ing provides more detail but sounds artificial and affects timbre, whilst reducing or even eliminating ambience cues.

 

I think that loudspeaker-driver material also affects (low-level) resolution in a significant manner.

The performance of some speakers totally collapses when you turn down the volume.

 

 

I have recently added the NAA to my HQPlayer server and was quite surprised by how much it affected low-level reproduction.

 

R

"Science draws the wave, poetry fills it with water" Teixeira de Pascoaes

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I have recently added the NAA to my HQPlayer server and was quite surprised by how much it affected low-level reproduction.R

 

Richard: It is quotes exactly like yours that caused me to post in the first place. Do you think the difference between with and without the NAA is measurable and, if so, what would that measurement show? I'm neither doubting your assertion, nor do I belong in the nothing counts unless its measurable camp, I'm just trying to better understand what is being improved in cases like your addition of the NAA.

 

Thanks

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People tend to use noise floor in a way that confuses the electronic definition with the audio one

 

the electronic definition is basically the signal to noise ration in decibels

 

the audio definition is subjective...if 10 different instruments are playing counterpoint each at an lower volume than the other, at what point do the lower volume instruments get muddied or indistinguishable from louder instruments.

 

1) power supply affects this... a principle means to improve "black space" are AC power regenerators so that you have complete isolation from shared power supply interference. Refrigerators, AC units and other noisy components sharing the line in from power utility do cause issues that normally aren't a problem until you plug in an audio system and are trying to reach extreme low signal resolution.

2) cables affect by changing the electrical load between components into a less optimal region for design performance

3) electronics affect by their own strengths or weakness in maintaining linearity of a weaker signal superimposed on a stronger one

4) speakers affect both by driver linearity under load and by excitable resonances for the cabinet/driver. One of the reasons I have always preferred electrostatics and dipole speakers

Regards,

Dave

 

Audio system

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Richard: It is quotes exactly like yours that caused me to post in the first place. Do you think the difference between with and without the NAA is measurable and, if so, what would that measurement show? I'm neither doubting your assertion, nor do I belong in the nothing counts unless its measurable camp, I'm just trying to better understand what is being improved in cases like your addition of the NAA.

 

Thanks

 

That is an excellent question.

Even though I can confidently say that I am able to identify a significant audible improvement by adding a NAA/NUC, I don't know how much difference would show in a typical set of measurements...the computer-DAC digital file reading-converting system is very complex, with several variables that can affect performance (both in digital and analogue) and adding a NAA/NUC changes quite a few factors which might also influence one's listening.

 

It would be nice if someone would perform the measurements since like you I'm also favourable to the importance of measurements but Achimago's measurements of various players didn't highlight any differences so I guess the outcome might be the same.

I wonder what else could be measured that would characterise the differences that so many people are reporting...

 

R

"Science draws the wave, poetry fills it with water" Teixeira de Pascoaes

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So what are people referring to when they make the "lower noise floor" comment?

 

Hi Sdolezalek,

 

Low noise floor sign nothing. Lower is relative value. There need reference level.

 

There are several referal point for noise:

 

1. -110 dB - for CD and 16 bit audio

 

2. -115...120 dB - for sound card/DAC 24 bit and better

 

3. -144...150 dB - for 24 bit audio

 

4. - 170 dB - pro level processing better 24 bit.

 

Low level can be considered in a certain context only.

 

Absolute noise level (SPL - sound pressure) depend on position of volume knob.

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So what are people referring to when they make the "lower noise floor" comment?

 

I think sometimes, it is just impossible to describe these things, especially when based on our current common understanding of hearing, it doesn't seem to make sense that we can hear a lower noise floor. The best way is to simply experience it. I see that you have the Oppo BDP-105D connected to the Bryston SP3. One thing you can try for yourself is to hook up your BDP-105D in stereo directly to your amplifier and turn on the Oppo volume control and listen to some music. And then hook up the BDP-105D stereo analog output to the SP3 input and then use the SP3 for volume control (Oppo at full volume) and have that hooked up to the amplifier. Assuming your Oppo and SP3 have the same power cabling and you used the same audio cables as interconnects, I suspect (although i don't know for sure), you may hear a "lower noise floor" when you hook up the Oppo direct to your amplifier and use the Oppo's internal volume control. It may not work out because the SP3's volume control maybe more transparent than Oppo's. But it's really worth a try if you just want to "hear" a "lower noise floor" in your system. Although I can see from your clean setup, it'll be a real chore to test this. And then again, you may hear no difference. But it's worth a try if you're really curious.

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I think sometimes, it is just impossible to describe these things, especially when based on our current common understanding of hearing, it doesn't seem to make sense that we can hear a lower noise floor. The best way is to simply experience it. ...

 

Thanks for the suggestion, I have tried it and couldn't hear much difference. I'm actually looking to step up from the Oppo to the T+A DAC 8 DSD or perhaps the new IFI Pro (if it ever materializes) but I need to wait until I can do DSD512 through an NAA as my computer needs to be in a different room than the sound system.

 

I guess the best way to think about "dropping the noise floor" is more generically -- that anything that adds noise, distorts, adds jitter, or adds anything reduces the clarity with which we hear the music. What fascinates me is that these improvements don't so much improve frequency range, or dynamics, or the typical stuff we measure but they somehow improve our ability to pick up the subtle cues about the space in which the music was recorded, the layering and depth of space of the performers, the number of different instruments we can individually pick out. That means all of these things are actually (or at least can be) in a 16/44 recording, we are just adding "noise" in our playback chain that, although perhaps not individually measurable as significant, does in the aggregate take away those tiny, but obviously critical, microcues about venue and space.

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Another aspect of this is not the noise floor with silence, but the noisefloor with music playing. An example might help.

 

Think of a room with no windows or doors, if you have no light sources in the room, a measure of light intensity is going to be extremely low. Then turn on a flashlight, the beam bounces off the opposite wall, off another wall etc. If you measure the light intensity in an area where the beam is not directly falling, it is now much higher. If the walls are painted white the ratio between the direct beam and non-direct fairly high, if the walls are painted black, it is much less. If the beam is brighter to begin with the non-direct light will also be greater.

 

When most people say the "noisefloor" is lower they are usually talking about a similar situation where the music itself is seeming to generate some low level sound which seems to fill in the space around the instruments. When it is decreased the space around instruments (voices etc) is decreased. Exactly what is happening hear is not really known, since it is very much a perceptual issue.

 

My guess is that the musical signal cause the perceptual system to develop the illusion of the original sound scape, but distortions in the electronics, speakers etc produce low level signals which don't properly correlate with the undistorted signal, thus the perceptual system cannot figure out exactly where to put them, so they wind up filling a large perceptual space between the "instruments". As distortions are decreased this diffuse sound that is not anchored to instruments also decreases, thus the "blacker" space between instruments.

 

This is something that is purely perceptual thus very difficult to measure with test instruments and essentially has nothing to do with actually measured "noise floor" of the signal.

 

John S.

Yes, John, I believe you are correct. I wouldn't say that it is "purely perceptual". As you said there are some anomalies in the reproduction that cause our perceptual processing system to be confused & not know where these sonic artefacts belong & so they become categorised as background. Agreed that it has nothing to do with measured noise floor of the signal & more to do with the dynamic stability of the reproduced audio.

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I often read equipment reviews that comment about a particular piece of equipment having a lower noise floor, or equipment that provides "blacker blacks" to use terminology perhaps better suited to televisions. Although I understand the concept, I'm not clear whether that is actually what people are hearing.

 

in this context, the reviewer's comment is likely to be related to SNR (sound to noise ratio)... and on not hearing anything (much) when there is nothing that should be heard during music playback.

 

moreover, in theory, if an audio component generates minimal noise, it should help to portray ambience and soft notes/quiet passages in a clearer manner… and, by inference, offer superior “dynamic range”.

however, a component is but one part of system. hence, the noise floor of the "quietest" piece of equipment may not be quite as important as the noise floor of the "loudest" component. that is not a loudspeaker, of course.

noise floor may be more relevant to head-fi than hi-fi today. when using “sensitive" headphones or IEMs (that would be in close proximity with ear drums and which isolate hearing to differing extents) some head-fiers have claimed that they hear faint HF background noises from some DACs and DAPs. during near silent or very quiet passages, or by simply plugging in... before pressing play.

as for ambient environmental noise: iinw, the minimum “acceptable” noise level of a pro studio, is 20dB A-weighted. some pros will only record on locations wherein ambient noise is 50-60dB below the softest sound being recorded (live rock concerts notwithstanding).

btw, ambient noise in an “average" library = 40dB. suburban home = 50dB. quiet rural area = 30dB. breathing = 10dB.

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Yes, John, I believe you are correct. I wouldn't say that it is "purely perceptual". As you said there are some anomalies in the reproduction that cause our perceptual processing system to be confused & not know where these sonic artefacts belong & so they become categorised as background. Agreed that it has nothing to do with measured noise floor of the signal & more to do with the dynamic stability of the reproduced audio.

 

I would also agree with John on this. In fact, I might go further to say that it seems as though many of the "improvements" currently being pursued by leading DAC and associated hardware and software designers might fall into the category of reducing the anomalies that cause perceptual confusion. To the extent these are difficult to measure, we are depending on the golden ears of the developers to figure out which changes are successfully reducing these anomalies.

 

In any case, it does seem to be working as we continue to make real strides forward in overall fidelity and in particular have taken the level of fidelity we can pull from a 16/44 file to a whole new level.

Synology NAS>i7-6700/32GB/NVIDIA QUADRO P4000 Win10>Qobuz+Tidal>Roon>HQPlayer>DSD512> Fiber Switch>Ultrarendu (NAA)>SMSL M500 DAC> Bryston SP3 pre>Levinson No. 432 amps>Magnepan (MG20.1x2, CCR and MMC2x6)

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