Debate Thread: Scott's Hi-res Audio Test - Page 50 - AVS Forum
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Old 07-02-2014, 03:47 PM
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Duplicate.

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Old 07-02-2014, 03:54 PM
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Originally Posted by krabapple View Post
The beauty part is, a claim made by even a questionable source can be independently verified. The phenomenon Penn & Teller are illustrating -- the untrustworthiness of perception and belief -- has been abundantly verified by science. P&T just made it more entertaining than an academic paper would.

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Originally Posted by krabapple View Post
And there it is again...the ever-popular,ever-*sighted*, 'huge improvement to the sound quality', from 'upgrading' a DAC or an amp.

The seductiveness of dubious beliefs like this are why the high-end will never die, though I don't know if Stereophile and its ilk will survive as print organs of the industry.

Why should high-end ever die?
I don't buy McIntosh but folks buy gear for their own reasons. It does not bother me a bit.


Fascinating, you have no idea what I upgraded from, yet you know all of this.
Note to self: turn off those damn internet cameras.

You can see my gear in my signature, all bought with my eyes open. Which you find them foolish?
(Hint: if price is your gauge, be careful, you do not know what I paid for them... and you never will)

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Old 07-02-2014, 04:54 PM
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Quote:
Originally Posted by RichB View Post
Why should high-end ever die?
I don't buy McIntosh but folks buy gear for their own reasons. It does not bother me a bit.


Fascinating, you have no idea what I upgraded from, yet you know all of this.
Are *you* certain of what you upgraded from? While most such 'upgrades' aren't going to result in an audible difference, much less a HUGE one, *in a bias-controlled comparison*, Chu raised a valid point: if your previous DAC or amp was *broken*, sure, a new one would likely be an audible upgrade...maybe even a huge one.

Did you verify that the previous gear was or was not defective? Or, did you perform a bias-controlled comparison? Go ahead, please amaze me with 'yes' answer to one or both of those.


Quote:
Originally Posted by RichB
Note to self: turn off those damn internet cameras.

You can see my gear in my signature, all bought with my eyes open. Which you find them foolish?
(Hint: if price is your gauge, be careful, you do not know what I paid for them... and you never will)
,
- Rich
I couldn't care less what your gear is, or what it costs, though that seems to be the only frame of reference you guys understand. What interests me, and audiophiles like me, is how you so confidently deduced the *cause* (you say it's the 'upgrade') of the *effect* you experienced ('hugely improved sound', you say).
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Old 07-02-2014, 05:00 PM
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Originally Posted by imagic View Post
Did you see the film? It seems like the author of that article has an Axe to grind. I saw the film and thought it was spot-on.

Penn and Teller are entertainers, not scientists. Why are they being held up as the standard in any case? It so happens that they are backed up by higher-standard evidence in this case. Perception is subject to error. People can fervently believe they 'heard' or 'tasted' or 'saw' (and for all I know, 'smelled' and 'touched' too) differences that demonstrably are not real.

That fact that humans are not perfect recorders and interpreters of objective reality is the reason why controls exist in science. That many people don't seem to realize this is one of the failings of science education as it is currently done.
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Old 07-02-2014, 05:32 PM
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Originally Posted by krabapple View Post
Are *you* certain of what you upgraded from? While most such 'upgrades' aren't going to result in an audible difference, much less a HUGE one, *in a bias-controlled comparison*, Chu raised a valid point: if your previous DAC or amp was *broken*, sure, a new one would likely be an audible upgrade...maybe even a huge one.

Did you verify that the previous gear was or was not defective? Or, did you perform a bias-controlled comparison? Go ahead, please amaze me with 'yes' answer to one or both of those.

Nope, not interested. My purpose is to determine which products for me to buy that meet my needs.
Amps are tough, it is hard to switch them. I once returned a 400 WPC Ice amp because it did not sound right especially in the bass.
I felt the same way about my friends Pioneer SC-07.
So called "Objectivists" would say that was non-sense.


Later they it was discovered that some of the ICE designs became non-linear when driving 4-ohm loads.
Multi-tone measurements often show greatly increased IM distortion than single tone tests.
When this information conflicts with a persons orthodoxy, then it is not given proper consideration.


So which is the better science, discovering an issue or diffierence and looking for the cause, or naysaying calling such observations flawed and invalid?

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Originally Posted by krabapple View Post
I couldn't care less what your gear is, or what it costs, though that seems to be the only frame of reference you guys understand. What interests me, and audiophiles like me, is how you so confidently deduced the *cause* (you say it's the 'upgrade') of the *effect* you experienced ('hugely improved sound', you say).

So, if I said it was a noticeable upgrade, you would be less hyperbolic?
For some reason, I do not believe you are honestly interested, so let's leave it at that


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Old 07-02-2014, 05:49 PM
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Quote:
Originally Posted by Chu Gai View Post
That's certainly one possibility. OTOH, what if the DAC was gradually going south because some aspect of it was gradually deteriorating such that it affected the FR? It's something you wouldn't initially pick up until one day you installed a new one. Perhaps Amir could comment on what aspects of a DAC might do something like this and how a user could test the DAC for themselves.
I have made many changes over the past 2 years.
In the process upgrading amps, I found that plugging my Sunfire 7400 into a Panamax 5400 power condition amplifier output was a bad idea.
Just moving it to a wall output was an obvious improvement. Since, then I have found a similar degradation when plugging my A51 into a Kill-a-watt.

There have been too many changes in my configuration to make a determination as to what exactly has improved the sound but it the best is has ever been.
I have been pleased with the BDP-105D DAC and HA-1, prior to that I had not used J River and USB DACs.

J River has a the ability to link zone to synchronize playback. Using the HA-1 as a preamp, the source can be switched using the remote and the sound compared.
I find there are differences in the way these two components sound.

It would be nice to capture the signal coming out of DACs and compare it back to the source material.
A similar process would be valuable measuring the amplified signal while driving loudspeakers.
Perhaps the technology is not there, but it would be a better test of real-world performance.

I would prefer instrumented tests than an countless SBTs or DBTs, which not matter the results, never seem to change anyone's mind.

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Old 07-02-2014, 06:32 PM - Thread Starter
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I post this in Scott's thread but thought would but useful to copy here. What is stated below is one of our pseudo engineering arguments that completely ignores perceptual models of hearing, the very thing we try to use to dismiss other audibility arguments:

----------


Quote:
Originally Posted by Mfusick View Post
It doesn't. Almost no system does. Typical consumer home noise floor is probably 40db so you need another 93db on top of that.
The noise floor number is not proper. SPL meters are "perceptually blind." You can't take their one number and have it mean anything with respect to audibility. See this article I wrote on proper way to analyze room noise: http://www.madronadigital.com/Librar...amicRange.html

Quote:
Originally Posted by Mfusick
The only people that have this full 93db of range (without significant compression or distortion) is the guys running very high end audio gear and/or DIY or pro audio gear and also have soundproofed and treated rooms to go with it. Around AVS there is some but in real life it's a needle in a haystack for normal folks.
Well, normal folks would not be concerned with high resolution audio, nor be married to threads like this . That said, there is data in my article about this:



As you see the noise floor of average system surveyed in the sensitive part of our hearing is around 10 spl and best systems go well below that, below the threshold of hearing.

If you look to the left you see your "40 db" number but that only holds true for very low frequencies.

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Old 07-02-2014, 08:23 PM
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Originally Posted by amirm View Post
I post this in Scott's thread but thought would but useful to copy here. What is stated below is one of our pseudo engineering arguments that completely ignores perceptual models of hearing, the very thing we try to use to dismiss other audibility arguments:

----------



The noise floor number is not proper. SPL meters are "perceptually blind." You can't take their one number and have it mean anything with respect to audibility. See this article I wrote on proper way to analyze room noise: http://www.madronadigital.com/Librar...amicRange.html



Well, normal folks would not be concerned with high resolution audio, nor be married to threads like this . That said, there is data in my article about this:



As you see the noise floor of average system surveyed in the sensitive part of our hearing is around 10 spl and best systems go well below that, below the threshold of hearing.

If you look to the left you see your "40 db" number but that only holds true for very low frequencies.

The above is based on the myth that the average listening room is the most common weakest link.
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Old 07-02-2014, 08:54 PM
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Speaking or DBTs and hypocrisy, I'll bet you can't hear a difference between that 'Sunfire Cinema Grand Signature' amp you've got and an inexpensive mid-fi receiver.

Derogatory terms like "analog bigot", "digiphobe", "internet eggspurts" have nothing to do with electrical engineering.
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Old 07-02-2014, 08:55 PM
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See this article I wrote on proper way to analyze room noise:
You need to read the forum rules.
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Originally Posted by DrDon View Post
A number of posts either promoting hits to other websites (not allowed on AVS)
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Old 07-02-2014, 09:09 PM
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Originally Posted by RichB View Post
Nope, not interested.
Figured as much. You're interested enough to report huge audible improvement from changing DACs or amps, but not enough to either 1) interrogate your own reasoning and 2) weigh the chances that you are right vs wrong.

Seen that before, will see it again.


Quote:
Originally Posted by RichB View Post
My purpose is to determine which products for me to buy that meet my needs.
Amps are tough, it is hard to switch them. I once returned a 400 WPC Ice amp because it did not sound right especially in the bass.
I felt the same way about my friends Pioneer SC-07.
So called "Objectivists" would say that was non-sense.

Later they it was discovered that some of the ICE designs became non-linear when driving 4-ohm loads.
Multi-tone measurements often show greatly increased IM distortion than single tone tests.
When this information conflicts with a persons orthodoxy, then it is not given proper consideration.
That's an interesting story of an amp that is either badly designed, broken, or poorly chosen (incapable of driving the user's system cleanly to the desired listening levels). Which coincidentally happen to the very cases where even 'objectivists' predict audible difference to be likely. Btw why would IM distortion sound wrong 'especially in the bass'?

I'd like to read more about that story if you have a reference/link.


But to kkeep this on track, do you think your case has to do with your old amp being badly designed or broken or incapable of driving their loads cleanly at the levels you desire? How might you rule those possibilities out?



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Originally Posted by RichB View Post
So which is the better science, discovering an issue or diffierence and looking for the cause, or naysaying calling such observations flawed and invalid?
You haven't demonstrated that you've 'discovered an issue'. You've made a sighted report of audible difference, with no other supporting evidence. A thing so common, and so often *wrong*, that from a scientific standpoint, it *isn't* valid as proof -- if you disbelieve me, try submitting a paper to the JAES or a psychoacoustics journal consisting only of such anecdotal evidence.

At best you propose a testable hypothesis: the 'upgrade' made a true audible difference. That's one that you don't seem interested in testing, nor (worse) do you even allow that *the difference could be completely illusory* (a possibility that *does* have to be considered in these cases, for very solid psychological and technical reasons).

Quote:
Originally Posted by RichB
So, if I said it was a noticeable upgrade, you would be less hyperbolic?
You mean, if you were less hyperbolic, would I be less skeptical? *How* noticeable? Really, I'd still be skeptical. You still don't seem to get why someone interested in objective evidence would be.
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Old 07-02-2014, 09:46 PM
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Originally Posted by krabapple View Post
Figured as much. You're interested enough to report huge audible improvement from changing DACs or amps, but not enough to either 1) interrogate your own reasoning and 2) weigh the chances that you are right vs wrong.

Seen that before, will see it again.

Well hammers see nails.


Quote:
Originally Posted by krabapple View Post
That's an interesting story of an amp that is either badly designed, broken, or poorly chosen (incapable of driving the user's system cleanly to the desired listening levels). Which coincidentally happen to the very cases where even 'objectivists' predict audible difference to be likely. Btw why would IM distortion sound wrong 'especially in the bass'?
Multi-tone tests seem to increase the measured IM distortion of some amp designs.
That statement had nothing to do with bass, that comment was related to some ICE amps driving 4 ohm loads.


Quote:
Originally Posted by krabapple View Post
But to kkeep this on track, do you think your case has to do with your old amp being badly designed or broken or incapable of driving their loads cleanly at the levels you desire? How might you rule those possibilities out?
Why would I want to rule out those possibilities?
I sell my old amps and I would not sell any amp that I thought that was malfunctioning. I sold a Outlaw 7500 after having it repaired and certified by ATI. I did some quick tests and still preferred the A51. In the bass, the A51 seems better controlled.
The purpose was not to prove something to anyone else, merely to pick the amp to keep. I don't like clutter.

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Originally Posted by krabapple View Post
You haven't demonstrated that you've 'discovered an issue'. You've made a sighted report of audible difference, with no other supporting evidence. A thing so common, and so often *wrong*, that from a scientific standpoint, it *isn't* valid as proof -- if you disbelieve me, try submitting a paper to the JAES or a psychoacoustics journal consisting only of such anecdotal evidence.
So many times in life when intending to select a piece of equipment, I accidently publish articles

Quote:
Originally Posted by krabapple View Post
At best you propose a testable hypothesis. One that you don't seem interested in testing or (worse) even admitting *stands a significant chance of being completely wrong*.
Hey, I could be wrong. Horrors.

Quote:
Originally Posted by krabapple View Post
You mean, if you were less hyperbolic, would I be less skeptical? *How* noticeable? Really, I'd still be skeptical. You still don't seem to get why someone interested in objective evidence would be.
I did not mean that.
Actually, I do not propose a hypothesis for the improvement in my system because too many changes have occurred and since I do not have the original equipment, no reasonable tests can be performed.

If you were to post that something or other improved your system, I would not ask you for your thesis and publish results.
I may or may not understand or subscribe to the changes (a $500 power cord comes to mind), but it would not upset me in the least.

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Old 07-02-2014, 09:52 PM - Thread Starter
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Quote:
Originally Posted by arnyk View Post
The above is based on the myth that the average listening room is the most common weakest link.
Sadly the myth keeps getting repeated by senior members here:

Quote:
Originally Posted by arnyk View Post

Listening rooms are very problematical. A normal residential room may have a noise floor of 40 dB SPL. If you play your music under 110 dB SPL which I strongly advise so you don't permanently damage your ears, we're back at 70 dB SNR.
If the room is not the "weakest link" then we better not use these arguments that are not correct technically anyway.

The second part of the above by the way is also not correct. Hearing damage does not occur at "110 db SPL." The formula for damage is X db at Y duration. You can't just state the former without the latter. Here are the US OSHA guidelines:



I have highlighted 110 db mark in red. As you see, their recommendation is to keep that below half an hour. Music peaks last milliseconds and not half an hour.

But that is not all. Note the part I have highlighted in yellow. It says dbA, not db spl. dbA applies a filter to the noise as to make it better approximate how we hear. OSHA's own regulation document where the above chart comes from has a nice conversion chart:



Find 110 on the right and then follow that curve to the left. That curve would tell you what 110 dbA spl translates into measured SPLs. Taking a frequency of 500 Hz, the allowable SPL for half hour is actually 125 db!

What's more, you can see that the meter is supposed to be in slow reading. Slow reading during music is going to average out the peaks. So real peaks can be even higher.

We measured our theater a while ago at 116 db SPL. To be sure, it can be scary loud at that level but in no time do I feel like I am going deaf in there.

Not saying you should go and listen to music at 125 spl all day. But let's not throw around arguments that we both agree are myths and not technically accurate.

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Old 07-02-2014, 09:57 PM
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Quote:
Originally Posted by krabapple View Post
Figured as much. You're interested enough to report huge audible improvement from changing DACs or amps, but not enough to either 1) interrogate your own reasoning and 2) weigh the chances that you are right vs wrong.

Seen that before, will see it again.




That's an interesting story of an amp that is either badly designed, broken, or poorly chosen (incapable of driving the user's system cleanly to the desired listening levels). Which coincidentally happen to the very cases where even 'objectivists' predict audible difference to be likely. Btw why would IM distortion sound wrong 'especially in the bass'?

I'd like to read more about that story if you have a reference/link.


But to kkeep this on track, do you think your case has to do with your old amp being badly designed or broken or incapable of driving their loads cleanly at the levels you desire? How might you rule those possibilities out?





You haven't demonstrated that you've 'discovered an issue'. You've made a sighted report of audible difference, with no other supporting evidence. A thing so common, and so often *wrong*, that from a scientific standpoint, it *isn't* valid as proof -- if you disbelieve me, try submitting a paper to the JAES or a psychoacoustics journal consisting only of such anecdotal evidence.

At best you propose a testable hypothesis: the 'upgrade' made a true audible difference. That's one that you don't seem interested in testing, nor (worse) do you even allow that *the difference could be completely illusory* (a possibility that *does* have to be considered in these cases, for very solid psychological and technical reasons).



You mean, if you were less hyperbolic, would I be less skeptical? *How* noticeable? Really, I'd still be skeptical. You still don't seem to get why someone interested in objective evidence would be.
Krab. I too tried to mix a set of very inefficient speakers with a pioneer receiver I did not do a DBT. not sure I needed to and here is why. With the AVR hooked up I found that it would cut out/thermal protect after about 40 minutes of running. It is spec'd to produce 110 watts or so all channels driven. When I hooked the speakers to my existing separate amp I could run the speakers indefinitely at similar levels. The amp ran hot, but never shut down. The separate amp is an old school Linn Klout which is rated for 80x2. I know that the pioneer was not defective as it is able to power other speakers just fine...it only crapped out when driving my mains.

I honestly wanted to see the receiver do well.

My question is whether or not it would have been necessary to do a DBT at all? I agree that levels should have been matched and they were not, but in this case I could have just waited the test out each time waiting for the pioneer to shut down.
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Old 07-03-2014, 12:07 AM
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Originally Posted by urapnes1 View Post
Krab. I too tried to mix a set of very inefficient speakers with a pioneer receiver I did not do a DBT. not sure I needed to and here is why. With the AVR hooked up I found that it would cut out/thermal protect after about 40 minutes of running. It is spec'd to produce 110 watts or so all channels driven. When I hooked the speakers to my existing separate amp I could run the speakers indefinitely at similar levels. The amp ran hot, but never shut down. The separate amp is an old school Linn Klout which is rated for 80x2. I know that the pioneer was not defective as it is able to power other speakers just fine...it only crapped out when driving my mains.

I honestly wanted to see the receiver do well.

My question is whether or not it would have been necessary to do a DBT at all? I agree that levels should have been matched and they were not, but in this case I could have just waited the test out each time waiting for the pioneer to shut down.

No one says every amp can drive every speaker well. I'm not sure what you are trying to illustrate, or why you would even care about whether a DBT is necessary. Clearly, if an AVR is going into thermal protect mode then something is *not right* in that system, no matter how it sounds before it shuts down. What on earth 'mains' were you driving?

I myself owned Pioneer Elite series AVRs exclusively for years, circa 2003-2012. Always in a satellite-sub setup, so the 'mains' were either NHT SuperOnes or Behringer 2030Ps. Bass of course was handled mainly by an active subwoofer. No such thermal shutdown issues plagued me.
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Old 07-03-2014, 01:40 AM
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Quote:
Originally Posted by krabapple View Post
No one says every amp can drive every speaker well. I'm not sure what you are trying to illustrate, or why you would even care about whether a DBT is necessary. Clearly, if an AVR is going into thermal protect mode then something is *not right* in that system, no matter how it sounds before it shuts down.
As I understand it the existing standards for power amplifier testing limit high stress testing to periods of time on the order of 20-30 minutes if memory serves. So a power amp that thermals out after 40 minutes is probably operating within specs.

My current system is centerpieced by a Denon 1913 and all by itself it thermals out before 20 minutes of operation when operated into Infinity Primus speakers that go below 4 ohms, near clipping with music and with subwoofers offloading it. I added a pair of low noise 120 mm computer fans (ca. $9 each) operated by a temperature activated controller that I obtained on eBay for less than $10. They seem to do the trick. It is a pretty slick setup with a digital display of temperature, status LEDs, etc.

Based on discussions with other audio club members this seems to be pretty typical for modern lightweight AVRs. With the added cooling it remains operational for over an hour, at which time the 110+ dB SPLs have satisfied my needs. The fans are not audible, even when running but without any music playing. Typically, I'm working elsewhere in the house and just want to fill the whole place up with sound.

I have a fair collection of legacy heavyweight separate power amps that weigh 2-3 times as much per watt-channel as my AVR. My recollection is that they will operate indefinitely under similar circumstances. I consider the fans to be a fair trade off in order to have a 7 channel 100+ wpc amp that is easy for me to lift and position in its cabinet, etc. Reality is that a comparable heavyweight AVR would cost me an additional $1000 or more.

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Old 07-03-2014, 05:57 AM
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Quote:
Originally Posted by stereoeditor
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Originally Posted by robertR
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Originally Posted by robertR
You also used the terms "complex and multidimensional," which is another way of saying "I can't really explain the audio engineering that causes these perceived changes."
Again, please stop putting words in my mouth to make it appear that I am
saying something different to what I actually said. I am a writer; I
choose words to mean exactly what I want them them to. In this case,
"complex and multidimensional" means literally that, as you would
realize if you actually read my lecture preprint.

Because you apparently won't do that simple thing, here is an example: a
listener in a blind test reports that a loudspeaker has "more bass" than
another. That is a description of his internal state of mind when
auditioning the speaker and there is no reason to assume he is lying.

So what parameters of the waveforms reaching his ears are relevant,
given that the speakers are in the same positions in the room as the
reference speakers? Low-frequency response. High-frequency response, as
a difference in the treble balance can affect the perception of low
frequencies. Woofer alignment Q. Lack of linearity at the preferred spl.
A strong pipe resonance in the port or line, if it's a reflex or
transmission line. A strong enclosure vibrational resonance in the lower
midrange. This speaker's woofers are at different heights from the
floor. Etc, etc.

Hence my use of the word "multidimensional" to describe the correlation
between what can be measured and what is perceived.
Citing "multidimensional" reasons for a speaker to sound the way it does
is nice, but speaker reviews are not the problem I was addressing.

As I show above, you questioned my use of the word "multidimensional" and I offered you 7 measurable parameters, changes in one or more will correlate with the perception that one speaker has "more bass" than another.
You conveniently omitted the fact that I specifically asked you to enumerate the measurable parameters that give things such as an amp or wire greater “liquidity”, more “drive”, greater “three dimensionality”, greater “solidity”, etc.

I was specifically addressing your misrepresentation of what I actually wrote. You didn't restrict that misrepresentation to exclude loudspeakers. That I chose loudspeaker sound quality as an example was the first one that came to mind. Please do not infer anything else from that fact, as you do in the next sentence.

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Originally Posted by RobertR View Post
These kind of terms appear frequently in your magazine. It seems apparent that you are unable to do so, which is a strong indication that such qualities do not in fact correlate with what exists in the components themselves, but arise only in the mind of the reviewer.

I don't see that am obliged to address people's arbitrarily expressed opinions on my magazine, not do I have any objection to people expressing those opinions. What I will do is to correct mistatements of fact and attempt to prevent people from putting words in my mouth, having me apparently saying things that I haven't. If you are sincerely interested in the correlations between what can be measured and what, as a result, is perceived, then, again, please read my AES lecture preprint and/or study the reviews in Stereophile where I write about these things.

John Atkinson
Editor, Stereophile

Last edited by stereoeditor; 07-03-2014 at 06:37 AM. Reason: To correct formatting of quoted text
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Old 07-03-2014, 06:36 AM
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Sadly the myth keeps getting repeated by senior members here:

If the room is not the "weakest link" then we better not use these arguments that are not correct technically anyway.
OK, Amir you asked for it.

It is not clear what the weakest link is in everybody's listening situation because everybody's listening situation is different.

However, the leading contenders are:

Listening room
Loudspeakers
Personal preferences for loud sound
Limitations inherent in the recordings we listen to

As far as studies of the noise floor of residential listening rooms go, they appear to be highly optimistic compared to my real world experiences. Let's face it, if most people were in a scientific study they would probably pre-optimize the area before the measurement tools get set up. That means, have the kids out of the house or doing homework, get the vacuuming done, the clothes and dishes washed beforehand, and do it late at night after the neighborhood has hopefully quieted down.

As far as loudspeakers go, most people use loudspeakers that are running out of gas technically starting at seemingly modest SPLs. For example one publication published measurements of loudpseakers performed by the NRC, and as bad as they looked (spurious responses only 30 dB down in some cases) they did most of their meausurements at relatively low SPLs and didn't even test but a minority as high as 90 dB SPL @ 1 meter.

Personal preferences for loud sound are another big area of mystery. For example I've measured my system > 110 dB SPL with several peak reading SPL meters but I rarely even hit 95 dB in actual listening for general pleasure. Very few audiophiles have even invested in the equipment to do this test even though it costs < 35 and takes only a few minutes of effort to use. In fact one audiophile asked whether he could rent it someplace!

Then there are the recordings we listen to that rarely have much more than 75 dB of dynamic range.

If we are advising people to build "Blue Moon" systems whose capability will only be used once every Blue Moon, we probably ought to make that clear.
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Old 07-03-2014, 07:50 AM
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No one says every amp can drive every speaker well. I'm not sure what you are trying to illustrate, or why you would even care about whether a DBT is necessary. Clearly, if an AVR is going into thermal protect mode then something is *not right* in that system, no matter how it sounds before it shuts down. What on earth 'mains' were you driving?

I myself owned Pioneer Elite series AVRs exclusively for years, circa 2003-2012. Always in a satellite-sub setup, so the 'mains' were either NHT SuperOnes or Behringer 2030Ps. Bass of course was handled mainly by an active subwoofer. No such thermal shutdown issues plagued me.
When you wrote what I quoted below, I interpreted it to mean that a bias controlled comparison is required in order to hear an audible difference. When in my experience a bias controlled comparison may not be necessary in order to notice a difference (big or small). In my case, the whole thing shut down which was quite audible. I verified that the gear was not defective...worked with other speakers just fine...and the speakers are fine with other amps that I had + a meter said they were not shorted out...but I did not need a DBT to tell me that the AVR wasn't going to work the way I wanted it to. The sound from the speakers when hooked to the AVR never sounded quite right...right up to the point where it let go.

Mirage M1-si in very big room...no subs either. As you say later...it could be that the AVR is just not right for my application, but I found that I did not need a DBT to prove that to me. I still wish that the AVR would have worked out better...would have been much more convenient.


"Are *you* certain of what you upgraded from? While most such 'upgrades' aren't going to result in an audible difference, much less a HUGE one, *in a bias-controlled comparison*, Chu raised a valid point: if your previous DAC or amp was *broken*, sure, a new one would likely be an audible upgrade...maybe even a huge one.

Did you verify that the previous gear was or was not defective? Or, did you perform a bias-controlled comparison? Go ahead, please amaze me with 'yes' answer to one or both of those."
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Old 07-03-2014, 08:04 AM - Thread Starter
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Originally Posted by arnyk View Post
OK, Amir you asked for it.
Good morning Arny. What I asked for was to not throw voodoo technical arguments at people where we make them worried about going deaf when there should be no concern. And make them think their rooms are noisier than any human ear would perceive.

I am hoping you confirm this in your next reply and we are once and for all are done with these lay arguments that have no foundation in science or reality.

Amir
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Old 07-03-2014, 08:39 AM - Thread Starter
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Originally Posted by arnyk View Post
As far as studies of the noise floor of residential listening rooms go, they appear to be highly optimistic compared to my real world experiences. Let's face it, if most people were in a scientific study they would probably pre-optimize the area before the measurement tools get set up. That means, have the kids out of the house or doing homework, get the vacuuming done, the clothes and dishes washed beforehand, and do it late at night after the neighborhood has hopefully quieted down.
Vaccuming??? clothes and dishes being washed? These are the assumptions we are making when we tell people their rooms have 40 db of noise? I sure hope not as if we did, our entire argument would be thrown out Arny.

Fortunate or unfortunately that is not the argument we throw at people. Here is what we tell them:

Quote:
Originally Posted by arnyk View Post
Good question. The first problem is to have a place to measure sounds in the 0-30 dB range. The book answer is that a typical quiet room in a quiet house measures in the 40 dB SPL range, and the SPL meters I've worked with don't say otherwise. Whether or not they can, may be a legitimate question! ;-)
See? We say that in a quiet room and quiet house we have these 40 db numbers not one with dishwasher sound and such.

You go on to say that your "SPL meter" told you that. Well, the SPL meter lies in this regard. It doesn't know the spectrum of human hearing system and gives you a single value. That single value is useless with respect to audibility of noise.

Even if the SPL meter told you the right number it still is non sequitur in this argument. Here is Fieldler in his paper again:



We are able to hear equipment noise 15 db below room noise. So even if your 40 db number were right, you needed to subtract this number from it and arrive at 25 db. The reason we are able to do this by the way is that room noise is all around us and the brain tunes it out as not being useful information. In contrast, noise coming from the specific points, i.e. your speakers, is considered non-invariant (pray coming to eat you) and something to note.

Net, net, the only way what you said was true is if we threw our everything we know about psychoacoustics/how we hear. Do you want to keep going there or should we dispense with these non-scientific arguments?

Before anyone questions the author and this information, this is an AES Journal paper and the author was president of AES. And Dolby "Fellow." In other words, no Pen and Teller. Ignore him at your peril.

Amir
Retired Technology Insider
Founder, Madrona Digital
"Insist on Quality Engineering"
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Old 07-03-2014, 09:01 AM - Thread Starter
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Going back to Scott's level discussion, I ran the same analysis on Arny's "jitter" files:



Focus on the last two: no jitter and max jitter. The difference in "level" is 0.6 db or so. Lets review what Arny said earlier:

Quote:
Originally Posted by arnyk View Post
False claim. Take two files and attenuate one by say 0.5 dB (clearly a case of fractions of a dB) and ABX them. It won't be the easiest ABX of your life but it can be done. If you use pure tones at midrange frequencies it is pretty easy. If you choose music with a lot of dynamics it may not be easy at all.
Is this a problem or not a problem? If it is a problem to have 0.6 db difference then why were we presented with this test? If it is not a problem, why do we make a big deal out of it???

The whole notion of using Replaygain in foobar to get these "loudness levels" for the purposes of Scott's test is wrong. You can't use a measure like this without understanding what it does. So here is a quick summary.

Research by Fletcher and Munson in 1940s showed that our hearing is most sensitive in the 1 Khz to 3 Khz range. We lose sensitivity rapidly as we deviate from these frequencies:



Each one of those curves shows "equal loudness" even though they are highly non-linear and nothing remotely close to a flat line.

Replaygain uses the standard technique of inverting these curves and using that to filter the music:



Ignore everything but the red curve. You see that it is an inverted version of the Fletcher Munson graphs. This filtering then gives the weighting for loudness.

Here is the critical thing: the algorithm has completely eliminated ultrasonics! Of course that is what it needs to do with respect to limits of our hearing range. If we are to accept this as fact, then we don't need to run Scott's test. We would be saying that nothing above 20 Khz matters as we try to analyze its loudness this way. The perceptual model in Replaygain invalidates the test and vice versa.
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Old 07-03-2014, 09:14 AM
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Originally Posted by imagic View Post
Did you see the film? It seems like the author of that article has an Axe to grind. I saw the film and thought it was spot-on.

I have seen the docu. Suggestion is that Vermeer was a painting by numbers painter. A close-up of the painting by numbers proof.


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Old 07-03-2014, 09:46 AM
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Originally Posted by RobertR
That's the best you can come up with? A disagreement over the quality of a painting? Weak.
You twisted my words by saying that i was implying that the video was fabricated. I wrote ''proof might be fabricated, actors might be used for interviews. You just do not know with these guys.''

What it comes down to for me is, i do not like their background, their trashy appearance, i do not like them swearin all the time etc... Might be a cultural thing. I am european and used to stuff like british Horizon and german Quarks & Co. Maybe folks in the US are used to circus clown-ish stuff like Penn & Teller: B*llsh*t!

Some info on Penn & Teller: B*llsh*t!
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Old 07-03-2014, 09:48 AM
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Originally Posted by amirm View Post
Going back to Scott's level discussion, I ran the same analysis on Arny's "jitter" files:



Focus on the last two: no jitter and max jitter. The difference in "level" is 0.6 db or so. Lets review what Arny said earlier:



Is this a problem or not a problem? If it is a problem to have 0.6 db difference then why were we presented with this test? If it is not a problem, why do we make a big deal out of it???

The whole notion of using Replaygain in foobar to get these "loudness levels" for the purposes of Scott's test is wrong. You can't use a measure like this without understanding what it does. So here is a quick summary.

Research by Fletcher and Munson in 1940s showed that our hearing is most sensitive in the 1 Khz to 3 Khz range. We lose sensitivity rapidly as we deviate from these frequencies:



Each one of those curves shows "equal loudness" even though they are highly non-linear and nothing remotely close to a flat line.

Replaygain uses the standard technique of inverting these curves and using that to filter the music:



Ignore everything but the red curve. You see that it is an inverted version of the Fletcher Munson graphs. This filtering then gives the weighting for loudness.

Here is the critical thing: the algorithm has completely eliminated ultrasonics! Of course that is what it needs to do with respect to limits of our hearing range. If we are to accept this as fact, then we don't need to run Scott's test. We would be saying that nothing above 20 Khz matters as we try to analyze its loudness this way. The perceptual model in Replaygain invalidates the test and vice versa.
You conveniently picked the A curve intended for spl levels up to 55dB


For music listening the B curve intended for the 55..85dB range is more appropriate.


In the hires debate the extended frequency range is far less important than the s/n ratio resulting from the bit depth.
Cranking up the volume to make the noise audible is far easier than growing additional hearing hair cells.
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Old 07-03-2014, 09:57 AM
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Vaccuming??? clothes and dishes being washed? These are the assumptions we are making when we tell people their rooms have 40 db of noise? I sure hope not as if we did, our entire argument would be thrown out Arny.

Fortunate or unfortunately that is not the argument we throw at people. Here is what we tell them:



See? We say that in a quiet room and quiet house we have these 40 db numbers not one with dishwasher sound and such.

You go on to say that your "SPL meter" told you that. Well, the SPL meter lies in this regard. It doesn't know the spectrum of human hearing system and gives you a single value. That single value is useless with respect to audibility of noise.

Even if the SPL meter told you the right number it still is non sequitur in this argument. Here is Fieldler in his paper again:



We are able to hear equipment noise 15 db below room noise. So even if your 40 db number were right, you needed to subtract this number from it and arrive at 25 db. The reason we are able to do this by the way is that room noise is all around us and the brain tunes it out as not being useful information. In contrast, noise coming from the specific points, i.e. your speakers, is considered non-invariant (pray coming to eat you) and something to note.

Net, net, the only way what you said was true is if we threw our everything we know about psychoacoustics/how we hear. Do you want to keep going there or should we dispense with these non-scientific arguments?

Before anyone questions the author and this information, this is an AES Journal paper and the author was president of AES. And Dolby "Fellow." In other words, no Pen and Teller. Ignore him at your peril.
Heavens! Ignoring a Good Fella is never a good idea!

For lthose who managed to scrap up the cash for two speakers, how much below the noise floor can we hear? And what about those who have 5 or more?

But what is the noise floor in a room? Is it around 40 as Arny said or is it on the order of 10 or so in the region where our hearing is most sensitive?

I have to wonder, yes wonder because I'm just a wondering type of guy, how might one have come up with what the ambient noise level is in a typical room? We can certainly poo poo things like vacuuming, dishwashers, people talking, and all that stuff as not being representative. But is it? What's the ambient noise in Manhatten and Queens, or Philly, Chicago, for those living near major roads, airports, where bus and subway traffic are the norm, for those whose neighbors have dogs, in apartments or attached multi family homes? Did the Good Fella study it? Lots of folks make really good money and live in such places. Some live far away and they're more fortunate with ambient noise.

So long as you focus myopically on Antarctica to the exclusion of everything else, you'll have a tough time understanding why people wear bikinis.

Just sayin...
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Old 07-03-2014, 10:25 AM
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But what is the noise floor in a room? Is it around 40 as Arny said or is it on the order of 10 or so in the region where our hearing is most sensitive?
I am in the office right now and don't have access to the files, but I will post the spectrum and level of the background noise in my urban dedicated listening room later.

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Old 07-03-2014, 10:32 AM
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I am in the office right now and don't have access to the files, but I will post the spectrum and level of the background noise in my urban dedicated listening room later.

John Atkinson
Editor, Stereophile
Could you elaborate on what method and equipment is being used to measure this background noise? Do you equate that to the "noise floor" of your room? Same or different?
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Old 07-03-2014, 10:36 AM
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You twisted my words by saying that i was implying that the video was fabricated. I wrote ''proof might be fabricated, actors might be used for interviews. You just do not know with these guys.''
If you're going to imply that something was fabricated, you need to provide evidence of that fabrication. Saying something "might" be true means nothing.

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Originally Posted by 8mile13 View Post
What it comes down to for me is, i do not like their background, their trashy appearance, i do not like them swearin all the time etc...
Once again, that is an ad hominem statement having nothing to do with the point being illustrated.
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Old 07-03-2014, 11:17 AM
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I was specifically addressing your misrepresentation of what I actually wrote. You didn't restrict that misrepresentation to exclude loudspeakers. That I chose loudspeaker sound quality as an example was the first one that came to mind. Please do not infer anything else from that fact, as you do in the next sentence.
In post #1390 , I explicitly asked you about amplifiers. I did so because your magazine goes to great lengths in its reviews to differentiate between the sound of amplifiers. You are, of course, perfectly aware that that kind of claimed differentiation between amplifiers is controversial (to say the least), and you are also well aware that such differentiation between loudspeakers is not. You chose not to respond to my specific question about amplifiers, and chose instead to talk about “more bass” in loudspeakers (which can be easily inferred from looking at its in-room frequency response). IOW, you chose to pick low hanging fruit. The inference is quite logical and reasonable.
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I don't see that am obliged to address people's arbitrarily expressed opinions on my magazine, not do I have any objection to people expressing those opinions.
“arbitrary”? Why would the sound of something that corresponds to measureable engineering parameters be “arbitrary”? Do you and the other people at the magazine never discuss why amplifiers and wires sound the way they’re described? Why wouldn’t you?
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If you are sincerely interested in the correlations between what can be measured and what, as a result, is perceived, then, again, please read my AES lecture preprint and/or study the reviews in Stereophile where I write about these things.
John, I have read the reviews in Stereophile, and no, they do NOT answer my question. Your responses give no indication that you or anyone else at the magazine can.
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