I think this is a key question and I have specifically been looking for the answer to this for decades (3 1/2).
So far this is the best I can do:
when listening to reproduced sound our brain is constantly compensating for and subtracting what it perceives as distortions (for our added listening pleasure!). The more it perceives as distortion, the harder this subliminal work becomes and the quicker listener fatigue sets in.
It seems to me, that if the distortion is simpler both in nature and in it's relationship to the program material, then higher percentages can be tolerated.
So far this is the best I can do:
when listening to reproduced sound our brain is constantly compensating for and subtracting what it perceives as distortions (for our added listening pleasure!). The more it perceives as distortion, the harder this subliminal work becomes and the quicker listener fatigue sets in.
It seems to me, that if the distortion is simpler both in nature and in it's relationship to the program material, then higher percentages can be tolerated.
Russell Dawkins said:
Sounds about right! Funny how perception and 'measured reality' act differently. Don't try to convince any of the hardcore objectivists that ears aren't microphones though 😉
This thread is so very interesting!
I'd like to say that I believe audio equipment is for the purpose of pleasing ears. . . and that the following reflects this opinion.
Tweeters
First off, the majority of dome tweeters just kill me. For instance, the famous Dayton Silkie sounds quite beautiful for about an hour. . . then its strong non-linear dispersion, which has been "spraying treble" (aka "NAIM Sound Effects") all about the room, has suddenly become noticable, as is the need for aspirin and silence.
I don't have tiled or carpeted walls, therefore, distracting dispersion patterns, wildly different between woof and tweet, become listening fatigue.
The Dayton Silkie is an excellent example of the "NAIM Sound Effects" style of tweeter. I'd also like to say that effects of any sort, are a distortion, and probably fit into the category of listening fatigue.
Mid peaks and crossovers
Typical:
The usual peak at a woofer's highest range is muted (masked) with crossover, resulting in a muffled noise (masking--a form of compression artifact). Then a high range driver is tapered into this noise to "blast" some clarity over top of it. Unfortunately, the high range driver may not have the ability to do this job in exactly the same dispersion pattern, so the "extra dispersion" is a peak, as soon as it bounces off the walls (while un-acompanied by the majority of the audio spectrum).
This is quite necessary because it sells more speakers--both instantly, and later for its replacement. 😉
Reference the difference in dispersion between a dome tweeter and a paper tweeter and consider for yourself, which is most likely to have a cohesive dispersion when teamed with a woofer or midbass.
Possible solutions for dome tweeters are, using the matching dome midrange, the "foam doughnut" dispersion controller, a slight horn loading, carpeting the walls, disposal, or setting the crossover point very, very high.
Of course, its possible to use full range drivers as midrange/wideband drivers, in the style of Harbeth Monitor 40. That would give a higher crossover point for the tweeter.
Efficiency
On the subject of speakers, I think that highly efficient speakers are now more important than ever before. Its because modern recordings may be run through a signal compressor and then probably delivered in MP3. If any additional harm is done to the audio source (which is already at disadvantage) then it may not succeed. Another important idea is prosound re-scaled for home environments--once more involving efficient speakers for realism.
Driver selection--maybe a "features" checklist?
An excellent, but tiny, example is the Tang Band 6-1/2 shielded driver. It can serve as either a woofer (up to 25w) or a wideband midrange (handles much more power that way).
Let's look at why its excellent. . .
It has a light (fast, high resolution) coated paper cone with a fiber (no shout) dust cap.
Its efficiency is 91db (more realism/dynamics)
It can do 45hz quite well (non boomy)
It can fit into enclosures only 60% of the size stated by specs, without loss of performance (most high speed drivers can do this).
Being non-peakish, is unnecessary to use a masking component, such as a zobel, and the crossover to tweeter can be very high.
This feature list can be used for driver selection criteria because it is likely to result in a non-masked sound without distractions--so listening fatigue may be considerably reduced.
Listening fatigue
So, listening fatigue can be either distractions (peaks) or masking (compression artifacts--"mask&blast"). In either case, its hard to hear over/through the non-music signals.
Opposite:
I think that transparency is the presentation of clarity, in cohesive dispersion, without distractions, and at a perceived pleasant frequency response (again, without distractions).
Transparency = distraction-free clarity.
The hallmark of clarity seems to be in being able to hear the natural ambients at the recording site, as if you are at that location instead of the listening room. That would also be a definition of transparency, if the clarity is also pleasurable (no distractions).
I also think that equalizations are mandatory as a seperate equipment, so that crucial component choices, througout the audio system, can be biased towards clarity rather than frequency response. Its a case of using the right tools for the job rather than compromising component selection. And, it need not be expensive.
Amplifiers and driver command.
Amplifiers do make a circuit with those speakers you have worked so hard to build. Some amplifiers have lovely control of the bass (very clear with rumbles) yet lose control at the upper midrange (shout), and some have control of the upper midrange and treble (very sweet but slightly "warm"). Some amplifiers have a flat frequency response that doesn't correspond to an ear (modern designs). Some amplifiers can cause speakers to project wide and deep (euphonic). These are the jobs and effects of amplifiers although some speakers are more or less helpful than other speakers.
Some amplifiers, like Tube, Tripath (BTL versions), LM1875 chipamp, and Hypex, do make it possible to have firm driver command across the entire audio band.
With the exception of the disposable Hypex, the rest of the group are low power amplifiers. The tube amp and miniature chipamp rely heavily on component selection and design decisions (plentiful examples here at diyaudio.com).
Just remember that 30w of 93db speakers is the same 107db as a home theater rig with 128w and 86db speakers. Here's a premium example of combating listening fatigue by choosing efficient speakers to open up a larger selection availability of really good amplifiers. Of course, I firmly believe in making hi-fi more easily achievable. Thus you can have really loud music instead of. . .
I'd like to say that I believe audio equipment is for the purpose of pleasing ears. . . and that the following reflects this opinion.
Tweeters
First off, the majority of dome tweeters just kill me. For instance, the famous Dayton Silkie sounds quite beautiful for about an hour. . . then its strong non-linear dispersion, which has been "spraying treble" (aka "NAIM Sound Effects") all about the room, has suddenly become noticable, as is the need for aspirin and silence.
I don't have tiled or carpeted walls, therefore, distracting dispersion patterns, wildly different between woof and tweet, become listening fatigue.
The Dayton Silkie is an excellent example of the "NAIM Sound Effects" style of tweeter. I'd also like to say that effects of any sort, are a distortion, and probably fit into the category of listening fatigue.
Mid peaks and crossovers
Typical:
The usual peak at a woofer's highest range is muted (masked) with crossover, resulting in a muffled noise (masking--a form of compression artifact). Then a high range driver is tapered into this noise to "blast" some clarity over top of it. Unfortunately, the high range driver may not have the ability to do this job in exactly the same dispersion pattern, so the "extra dispersion" is a peak, as soon as it bounces off the walls (while un-acompanied by the majority of the audio spectrum).
This is quite necessary because it sells more speakers--both instantly, and later for its replacement. 😉
Reference the difference in dispersion between a dome tweeter and a paper tweeter and consider for yourself, which is most likely to have a cohesive dispersion when teamed with a woofer or midbass.
Possible solutions for dome tweeters are, using the matching dome midrange, the "foam doughnut" dispersion controller, a slight horn loading, carpeting the walls, disposal, or setting the crossover point very, very high.
Of course, its possible to use full range drivers as midrange/wideband drivers, in the style of Harbeth Monitor 40. That would give a higher crossover point for the tweeter.
Efficiency
On the subject of speakers, I think that highly efficient speakers are now more important than ever before. Its because modern recordings may be run through a signal compressor and then probably delivered in MP3. If any additional harm is done to the audio source (which is already at disadvantage) then it may not succeed. Another important idea is prosound re-scaled for home environments--once more involving efficient speakers for realism.
Driver selection--maybe a "features" checklist?
An excellent, but tiny, example is the Tang Band 6-1/2 shielded driver. It can serve as either a woofer (up to 25w) or a wideband midrange (handles much more power that way).
Let's look at why its excellent. . .
It has a light (fast, high resolution) coated paper cone with a fiber (no shout) dust cap.
Its efficiency is 91db (more realism/dynamics)
It can do 45hz quite well (non boomy)
It can fit into enclosures only 60% of the size stated by specs, without loss of performance (most high speed drivers can do this).
Being non-peakish, is unnecessary to use a masking component, such as a zobel, and the crossover to tweeter can be very high.
This feature list can be used for driver selection criteria because it is likely to result in a non-masked sound without distractions--so listening fatigue may be considerably reduced.
Listening fatigue
So, listening fatigue can be either distractions (peaks) or masking (compression artifacts--"mask&blast"). In either case, its hard to hear over/through the non-music signals.
Opposite:
I think that transparency is the presentation of clarity, in cohesive dispersion, without distractions, and at a perceived pleasant frequency response (again, without distractions).
Transparency = distraction-free clarity.
The hallmark of clarity seems to be in being able to hear the natural ambients at the recording site, as if you are at that location instead of the listening room. That would also be a definition of transparency, if the clarity is also pleasurable (no distractions).
I also think that equalizations are mandatory as a seperate equipment, so that crucial component choices, througout the audio system, can be biased towards clarity rather than frequency response. Its a case of using the right tools for the job rather than compromising component selection. And, it need not be expensive.
Amplifiers and driver command.
Amplifiers do make a circuit with those speakers you have worked so hard to build. Some amplifiers have lovely control of the bass (very clear with rumbles) yet lose control at the upper midrange (shout), and some have control of the upper midrange and treble (very sweet but slightly "warm"). Some amplifiers have a flat frequency response that doesn't correspond to an ear (modern designs). Some amplifiers can cause speakers to project wide and deep (euphonic). These are the jobs and effects of amplifiers although some speakers are more or less helpful than other speakers.
Some amplifiers, like Tube, Tripath (BTL versions), LM1875 chipamp, and Hypex, do make it possible to have firm driver command across the entire audio band.
With the exception of the disposable Hypex, the rest of the group are low power amplifiers. The tube amp and miniature chipamp rely heavily on component selection and design decisions (plentiful examples here at diyaudio.com).
Just remember that 30w of 93db speakers is the same 107db as a home theater rig with 128w and 86db speakers. Here's a premium example of combating listening fatigue by choosing efficient speakers to open up a larger selection availability of really good amplifiers. Of course, I firmly believe in making hi-fi more easily achievable. Thus you can have really loud music instead of. . .
I think you guys are missing the obvious. Often when listening fatigue sets in, you can trace it back to a recent and excessive exposure to specific things like a female voice reciting a list of honey-doos. Oddly the problem is not related to high SPL but to repeated exposures...
peter_m said:
You know this is very true.
Bad day yesterday - lots on my mind - wife adding more - kids adding as many problems as they can think of too. As the day settled down (everyone went to bed!!) I wanted to soothe my nerves with some music. Only when I started to listen it sounded terrible - everything was grating on my ears and my nerves. But this was excetly the same system that I have loved in the past!?
So I forced myself to listen, for almost 1 1/2. After about 1/2 hour of grating, it started to sound better, then it was actually relaxing and all of a sudden, it sounded great again!
Wow! Talk about the system improving as it warmed up!!
We totally discount how are minds control what we hear NOT our ears. The ears are a simple passive conduit - the mind does the interpretation and this is hardly based solely on the information that is provided by the ears.
I hate it when I try to be a smart alec and end-up contributing... how did that happen? Well, while I'm at it, I might as well mention that any type of cardio-exercise is great for relaxing and blowing off steam. I personally prefer cycling but when it's too cold I settle for jogging. As a bonus, you sleep like a baby... and get in a better shape... and get away from the in-home stressing factors.
peter_m said:
But you see, thats just it. People think its a joke, but its a far more powerful factor than they appreciate.
The excersize part is well know, but not always practical.
gedlee said:
I guess it contributes what some people are saying. Perception is always very subjective...
Also the pharmaceutical companies have built a whole industry around "practical" solutions... but that's off topic... for now.
Peter
What about getting VERY drunk beforehand?? i have never heard a bad system at a good party 😀 although maybe i did but couldn't remember 
And any distortion usually gets drowned out by your own voice, or someone else's, or a combination of the two.
Just put your drink down BEFORE turning the amps on
And any distortion usually gets drowned out by your own voice, or someone else's, or a combination of the two.
Just put your drink down BEFORE turning the amps on
peter_m said:
I think that I would say that there is a subjective part but there is also an objectively quantifiable part. The basic function of our hearing is ruled by laws and principles and these are the same throughout individuals. And there are the totally subjective things. The idea is to get to those things that are invariant with individuals and exclude those things that are not - at least in the science. Let the marketing guys deal with the completely subjective parts - they are very good at manipulating those.
The worst form of listening fatigue is from a bitter, unforgiving, self-centered, self-absorbed, High Maintenance Wife or GF that you choose when you where "thinking" with the wrong Head.
Heres my pennies worth,
I have worked in the HiFi industry for the last 18 years and as far as I can tell you are all right.
This can be down to problems with the speaker response, room related or design related. Problems with the crossover or drivers, especially the top end of the mid bass drivers in two way systems.
It can also be related to the electronics, EMC issues seem to cause all sorts of problems in terms of making the sound hard and fatiguing. But a simple grounding error can cause problems.
I have even heard speaker cables make a difference on some occasions and in one test whilst I was trying to make two identical CD players sound the same; discovered that the sound difference was down to different mains cables. I spent two days trying to work out what was different before someone else suggested that. I simply didn't belive it could be important.
However as the MD often says the best upgrade to most systems is a glass of red wine (or beer depending on your preferance). I can also confirm I have days when every thing sounds aufull and I just have to give up on doing any usefull listening tests.
Regards,
Andrew
I have worked in the HiFi industry for the last 18 years and as far as I can tell you are all right.
This can be down to problems with the speaker response, room related or design related. Problems with the crossover or drivers, especially the top end of the mid bass drivers in two way systems.
It can also be related to the electronics, EMC issues seem to cause all sorts of problems in terms of making the sound hard and fatiguing. But a simple grounding error can cause problems.
I have even heard speaker cables make a difference on some occasions and in one test whilst I was trying to make two identical CD players sound the same; discovered that the sound difference was down to different mains cables. I spent two days trying to work out what was different before someone else suggested that. I simply didn't belive it could be important.
However as the MD often says the best upgrade to most systems is a glass of red wine (or beer depending on your preferance). I can also confirm I have days when every thing sounds aufull and I just have to give up on doing any usefull listening tests.
Regards,
Andrew
Gifandy is correct. The cd player contains an op amp. That is an amplifier. Power+Input=output. A change to the power will change the output.
However, if this happens depending on mains cable (power cord) selection, then I think that the CD player has an garbage quality power circuit design onboard, and the unit should probably be disposed or its power circuit corrected.
Probable: The CD player wasn't specifically designed to offend the ears. There's two identical units (mentioned above) and one sounds different (offends). So, I think that one of them has a manufacturing defect.
EDIT: Please describe the nature of the audibly defective unit. Is it too-brilliant, or is there a sort of buzzy muck at the midbass?
However, if this happens depending on mains cable (power cord) selection, then I think that the CD player has an garbage quality power circuit design onboard, and the unit should probably be disposed or its power circuit corrected.
Probable: The CD player wasn't specifically designed to offend the ears. There's two identical units (mentioned above) and one sounds different (offends). So, I think that one of them has a manufacturing defect.
EDIT: Please describe the nature of the audibly defective unit. Is it too-brilliant, or is there a sort of buzzy muck at the midbass?
gfiandy said:
If you truly (either of you) believe this to be so, give me a realistic model of how the power cable can be affecting the SQ on a CDP. Effects given must be in the real world, say, no more than 60dB below signal level. No flawery 6moons type descriptions please.danielwritesbac said:
I agree strongly with danielwritesbac's last quoted paragraph. If en EE in the 21st century cannot design a decent PS for an opamp, they should hand back their degree.
My previous post, which far more succinctly stated my position on this subject was deleted. How amusement.
Brett,
a friend of mine has a new Samsung DLP 61" TV with a brand new Scientifi Atlanta HD cable box. When ever the two are plugged in the same power outlet, a very audible hum can be heard through the TV when watching cable TV.... as soon as the TV and cable box use separate power outlets the hum disappears... both new and modern devices... **** happens, specially when mass produced in Asia...
Peter
[Post edited by moderator]
a friend of mine has a new Samsung DLP 61" TV with a brand new Scientifi Atlanta HD cable box. When ever the two are plugged in the same power outlet, a very audible hum can be heard through the TV when watching cable TV.... as soon as the TV and cable box use separate power outlets the hum disappears... both new and modern devices... **** happens, specially when mass produced in Asia...
Peter
[Post edited by moderator]
I'm not seeing the relevance of this. Your example is two disparate items connected as a system. I was asking about a powercord having an effect on a single CDP.peter_m said:
Assuming there is some design flaw or implementation issue in the PSU of said mass produced CDP, other than gross faults like easily audible hum etc, please explain how and why a powercord can make a difference.