The "Official" All CD Players Sound the Same Thread - Page 3  

this seems to be the major point of disagreement. do you have specific references to support what you describe here as dogma? If one agrees with these assumptions then you would be correct by definition--this is a circular argument presented without evidence presented but I must admit, the verbage was crafted in a creative an eloquent way.

Two Chocolate bars made by diferent companies can be made with all the same ingredients but people find the taste to be diferent between brands. I would argue that there are a lot more differences in cd players than chocolate bars but no one requires double blinds tests to believe that they taste different. oh yes, the resolution of the human taste and smell system must be much better than hearing, right? hmmmm.

Ok people if we're going to invoke 'the scientific method" here we need to invoke it for real--under the right conditions with other variables eliminated, with adequate sample size, and with clearly defined and not GENERALIZED hypothesis (i.e. just because two cd playes cannot be discriminated in a DBT doesnt mean ALL cant until all have been compared under the same circumstances.

If that is the way you would all like to go with this then lets do it and find out. Science isnt easy and I am absolutely sick of people invoking science in this forum and misusing terms and making dubious and broad generalizations based on loosely (if at all) associated comparisons presented without references.

I have been personally attacked by individuals claiming that I am using somatoform delusions to create differences between components or wires that are not there. Furthermore I have been accused by these individuals that I (or my subconscious mind) am creating these in order to justify the expense of the gear that I have (which is very modest compared to some here).

Have you ever considered that it could also be just the other way around? If you want to go down that road then consider that those of you saying there is no diference, who are using what you describe as science (which is employed in a non scientific way) to justify your assertions, are just as susceptible to the claims that you are justifying your pourchases of more 'downscale' gear. Then in order to justify that it is just as good as the ultra high end gear and you use "psychoacoustics" to make this assertion.

Now I, myself, could fit into this category and i am NOT personally making this argument. I am just pointing out that since I have been personally attacked with this argument it can equally easily be turned right around so please do not make this assertion in the future.

As for me i think the jury is out. I have not heard a lot of difference between cd players myself-then again I have not spent hours making comparisons myself either. I have heard significant differences between dvd player audio--the pioneer dv45a compared to an older pioneer 1st generation player and the denon 5910 but for dedicated cd players I have not done this and am open to hearing more about what people think

Just my HO.

They are different sensory systems, for sure -- and their sensitivities are differenet, for sure. And as for chocolate bars, where is this study where two bars were found in a *blind* taste test to be different, when the ingredients were 'the same'? Was this a triangle (ABX) test? Was it blind at all? Obviously in a 'sighted' test you could even get people to call two halves of the THE SAME chocolate bar 'different tasting', by simply packaging them differently or otherwise giving them 'cues' to expect a taste difference. So please point me at the citation that found this rather remarkable result you report.




There is no 'perfect' experiment. So it generally suffices that the methods be sound and the conclusions be presented with scientifically sound qualifiers..that is, they do not exceed their data.

Which was the case for Meyer and Morans' work, and for work like this:

http://www.aes.org/e-lib/browse.cfm?elib=12375

(you need to pay $20 to get the whole paper, but another version of it is here:

http://www.nhk.or.jp/strl/publica/labnote/lab486.html



If by that jargon you mean, you have 'heard differences' that weren't real, but were due to perfectly normal effects of psychological confounders, the ones that scientists routinely take into account when designing experiments testing audio perception, then there is no reason for you to be offended. They just called you 'human'.




Meanwhile, 'audiophiles' accuse others of not have gear, or ears, sufficiently
good enough' to discern these physically unlikely differences....missing again the elephant in the room, which is the intrinsically vulnerable nature of sighted evaluations of audio.

Not sure if you have these:

Pholmann, Ken C. '6 Top CD Players: Can You Hear the Difference?' Stereo Review, Dec 1988, pg 76-84.

Phollmann, Ken C. 'The New CD Players: Can You Hear the Difference?' Stereo Review, Oct 1990, pg 60-67.

Yes, that test compared an RCA carousel player $80, to ones costing $1000s. The panel included a number of people and some in their early years. Usual outcome Unfortunately he didn't name the expensive players.
The second is a follow up showing how bullet proof the player was.

You really think that it is well written? Or, perhaps you happen to like what the author has to say? Seems like he has an ax to grind, not writing a legitimate paper.

If one CD player can do that, then it has gross design flaws to go with it. I'd rather not pay for such flaws.

Well, thanks for the compliment about my word-smithing skills. It is my stock in trade.

Anyway, I am admittedly not an expert in any field related to engineering or acoustics. You know who is?

jj_0001. I urge you to invite him to this thread. He probably knows more about this subject than anyone at AVS, bar none. He's been working in the audio-engineering and psychoacoustics fields for decades, is a member of prestigious audio engineering societies, the recipient of many such professional awards, and a co-inventor of MP3 and AAC, among other things. Fair warning, however. jj does not suffer fools gladly.

http://www.avsforum.com/avs-vb/member.php?u=7641556

Here's a link to his home page (linked to on his profile here at AVS, so I'm not giving away any non-public information):

http://home.comcast.net/~retired_old_jj/


You don't need to re-invent the wheel and conduct the tests yourself. Others have done the homework for you, and fortunately others who are experts can explain a great deal about why you shouldn't and probably cannot hear audible differences among well-built players with good testing protocols and bias controls in place.

Again, ask jj (or arnyk, who is already in this thread). I'm not the expert here. It's out of my depth when it comes to explaining the why in technical terms. I rely on the expertise of others who are experts in this field and I trust them when they have proven themselves reliable, much like I don't have to be an astrophysicist myself to have learned cool facts and details about the behavior of solar mass stars on their main sequence.

Most likely not on line but, you can request your local library for an inter library loan or copy of any of these articles. They in turn go out to other libraries that have those back issues and send a copy. A rather simple and inexpensive way to get copies
I have done this many times

And, perhaps most in the industry

Letsee, the architecture of the CD was pretty well set by 1981. Does that mean that this person was talking about psychoacoustics as it was nearly 30 years ago?


Bascially, high frequencies aren't propagated very far.


Most microphones used for recording have response that is rolling off above 15-20 KHz, and ditto for our speakers.


Masking, not the high frequency response of the human ear is the primarly limit to hearing high frequency sounds above 16 KHz.


Most musical instruments naturally roll off the highs above 10 Khz or less.


Agreed.

Never happens, at least with chocolate. If nothing else, the beans are far from being a commodity, quality controlled product.

Recipies for food products are generally carefully guarded secrets. Furthermore, flavor is affected by subtle variations in basic process controls.


You can argue that at your own risk, basically exposing your complete and total ignorance of both the electronics and food industries.


One of the best books around about subjective testing (including of course detaled discussion of a number of different methods for doing DBTs) was written by the head brewmaster for Strohs. This book is widely referenced both inside and outside of the food industry.


You're comparing apples and oranges, if you hadn't noticed.


Nobody is saying that all CD players sound alike except people who seem to believe that all CD players sound different. It is a straw man. It is an excluded-middle argument.


Just because you haven't done your homework, doesn't mean that the references that have been cited don't exist.


That's not a personal attack, its a factual statement about the human condition.



There are scientific studies that show that people get more pleasure from tasting mid-priced wine if they are told that it is very expensive. Again, don't take it personally when people accuse you of being human.


Early and often.


Class warfare gets sooooo tiring. I can't speak for everybody, but there are very many people of the scientific evaluation persuasion who are perfectly capable of , and who have a long track record of, paying whatever it takes to get the best sounding equipment.

For example take me. In 1983 I paid nearly a $grand for a CDP 101 on the strength of listening to a number of digital recordings of a local orchestra. BTW, ever price digital recording equipment in 1983? I also paid premium prices for CD media and travelled all over the midwest buying it because that is what it took.


Trust me, the carefully-performed listening tests preceeded our study of psychoacoustics. It is a fact that much of the literature of psychoacoustics became generally known *after* 1983. AFAIK one of the landmark texts in the field of Psychoacoustics by Zwicker and Fastl, had its first edition published in the very late 1980s or early 1990s. I didn't read it until Y2K at the earliest.

We knew what we heard, but we didn't know exactly why.


You really need to study what is currently known about perception, learning, and memory, and how the brain accomplishes it for your own peace of mind. You're obviously taking it personally when all that is happening is that people are accusing you of being human.


There have been many juries. Just because you are so poorly informed doesn't mean that they haven't happened. The juries are coming back all the time.

One of the ironies of the study of hearing is that the more we learn, the more we learn about how insensitive the ear really is. For example many golden ears are fighting the battle of Fletcher and Munson, but after Zwicker and Fastl we know that Fletcher and Munson were bloomin' optimists!

If the insensitivity of the human ear were only what Fletcher and Munson thought it was, MP3s as we know them would be completely impossible.


I've spent weeks making comparisons of just CD players, and then there are the other classes of audio components.


There are probably only a few dozen people in the world who have done really good comparisons of CD players, level matched within 0.1 dB 20-20KHz, time synched within a few milliseconds, and double blind. I'm very fortunate to be one of them.

Sorry, I haven't read the whole thread, but I'll bring up something I've posted before in threads like this. My Esoteric DV-50 has 3 different digital filter settings. Switching between them makes an obvious difference. So, if my player can sound like 3 different players, how can all players sound the same? If one person can't hear the difference between any 2 players, that's fine, and I don't doubt it in the least. However, that doesn't mean it's rule for all players.

larry

In a double blind comparison? I assume you realize how prone to error -- and worthless as evidence -- a 'sighted' switching comparison can be.


Can it? I would suggest perhaps at least two of them are badly distorting on output, then.


Rest assured, no one other than trolls say it is the *rule* for *all players*.

I haven't participated in any double-blind medical trials, either. That doesn't lead me to assert that all treatments claimed to work probably *do* work, does it?

One reason CDPs are not expected to sound different, is that their bench-measured performance data (when level-matched) do not routinely differ enough to warrant it.

Maybe you should start reading and stop your pointless posting?

Meyer and Moran's experiments investigated whether SACD (DSD), a
~3MHz sample rate/1 bit format touted as sounding better than CD, could be distinguished from the same file converted to Redbook (44.1 kHz/16 bit). Months and hundreds of subjects later, using both 'high end' and 'low end' SACD players, the answer was: none could do it a rate better than chance, unless playback level was raised to ear-splitting.

If that's the case for DSD vs CD, which were supposed to be obviously different, why do expect CD vs CD should sound different, unless one player is *broken*?



You are misreading, or rather, indulging in egregious quote-mining. THe NHK investigators very admirably couched their conclusions in the strictest scientific language: their experiments (like most experiments) cannot *absolutely rule out the possibility* that someone, somewhere, under some condition, might be able to tell the two test conditions apart. They cannot 'prove a negative' in other words. But they can report that under THEIR conditions (which improved on Oohashi's), with THEIR subjects (who included 'golden ears' who were re-tested when they scored well) the hypothesis of 'difference' was NOT supported. They also quite correctly note that more tests on more subjects would increase the power of the finding.



You don't know what they said, since you haven't read it, as usual.

Yes, some people can hear above 21 kHz. Children, typically. The rare adult as well, might hear out to a few more kHz beyond 20. Your job is to prove that is what so many 'audiophiles' are hearing when they claim to hear differences, and to prove it matters at all to recorded music played back in home environments. The preponderabce of evidence for both is in the other direction.

then why have you not changed the strawman title of your thread?

Correct me if I am wrong, but I understood that the study showed that a difference *could* be heard via the SACD players, but this was due to difference in mastering between the high resolution DSD and PCM tracks. A difference however could not be heard when the DSD track was downsampled to 44.1 kHz.


I disagree with your assertion here. I do not believe that the outcome of the Meyer and Moran study provides any implication to the discussion in this thread. It does appear to be one of the more thoroughly conducted studies though, in stark contrast to any of the studies brought forward so far to this thread.

With regard to your comment that DSD vs CD is supposed to be more obviously different to CD vs CD, I also initially expected this to be the case but my subjective experience, when trying out a number of CD players in my system, has been that the difference in sound of better quality CD players is usually much more apparent than that of SACD vs CD.

And to pre-empt the usual "did you level match, time sync, double blind test" - no I didn't. But if this response cannot be met with reasonably conducted DBT showing the converse of my subjective experience then it is not fair to dismiss it outright.


Now this sounds like a fair representation of science to me. We must be absolutely certain that the results presented from studies conducted are placed within context and fair conclusions derived. I think this is a gripe that some are having with regard to this topic, is that far reaching conclusions are asserted from very limited (and sometimes questionable) tests.

I did a little research about what those 3 filters do. There are actually 4 different PCM filters on the CS 4398 DAC chip, but for some reason Teac chose to expose only 3 of them to end users.

The 4 CS 4398 only vary significantly from a technical standpoint in the audible range when operated at 44 or 48 KHz sample rates. CD format is 44 KHz, but some DVD-Audio formats, particularly those associated with video, might be 48 KHz. The remaining 96 KHz and up sample rate audio for DVD-A would push any effects, even those that are just barely measurable with very sensitive equipment, outside the audio range by quite a bit.

Three of the filters are about 3.2 dB down at Nyquist (22 or 24KHz depending on whether the sample rate is 44 or 48 Khz), and one is more like 6.5 dB down at Nyquist. All are essentially perfectly flat up to 16 KHz or more with either 44.1or 48 KHz sampling.

Since all of the filters are flat up to about 16 KHz even from a measurement standpoint (within 0.1 dB or so), their effects would be sonically benign with just about any musical program material, even if there would have been a brick wall filter just above 16 KHz. But there isn't. The filters vary as to whether their effects are varying degrees of gentle up to 20 KHz.

If the -6.5 dB filter is even available to users, it is questionable whether its effects would be even subtly audible. But, it might be audible with carefully-selected source material and frequent fast switching.

The remaining filters can reasonably expected to be indistinguishable from each other, and indistinguishable from other good CD players.

If switching between these filters makes "an obvious difference", said obvious difference exists only in the perceptions of the listener based on his foreknowlege of the settings of the player's controls.


That would be a good question if your player actually sounded like 3 different players. But it doesn't. 3 of the possible 4 filters in it surely sound like every other good CD player.

The fourth filter, if even implemented in your player, is a sort of a trick filter, and it would only sound subtly different from a good CD player with fast switching and carefully-chosen source material (probably something like pink noise).


The only people who are saying that all CD players sound the same are the people who don't believe it. It's a straw man that they are promoting for reasons that have nothing to do with intellectual honesty.

The people who are saying that CD players sound the same are restricting their comments to "good" players, not players with trick filters that are essentially designed to sound different.

In the case of the DV50/60, even the trick filter if actually implemented, makes only a subtle audible difference under special test conditions that are different from normal listening to music for the purpose of enjoyment.

Agenda? Well if I hear a difference between two CD players and my wife (without being aware a change to my system had been made) hears it too and I post that info, what is my agenda?

Conversely when I make such a post I am told it is all psycho something and coincidence, unsolicited info, that to me seems to be an agenda.

This may lie at the heart of the turbulence. What is a, "knowledgeable person?"
One who has spent 50 years listening to music as a hobby/passion or an engineer/psychologist?

if a poster, in earnest provides you information that he and so and so have heard a difference between two units why not learn from that?
Your argument is not consistent.

seems to me there is a difference between sharing thoughts on sound and being told that your perceptions of sound are not valid.

It also seems to me that if a poster is clearly not interested in a pseudo scientific evaluation of sound and states so his wishes should be respected. I personally promise to never post or comment on a thread about CD differences if the OP requests that only measurable scientific data be submitted. Why can't you do the same?

Seems to me that it is really just a vocal minority that would not accept the perception of a fellow poster posting in earnest. His comments are useful to everyone here. To you because it gives you yet another platform to carry on.

Because there's nothing to learn from that.

If I told you I took an aspirin, and my eyesight improved, what would you learn from that? That aspirin improves your vision?

Typical one sided view. To me it looks like both sides are just trying to prove their view is the correct view, neither seems to have an agenda.

BTW, I love the "my wife heard it too" argument, very convincing.