How to get better sound? - Page 2

Wheels spinning!

This. AFAIK, at 96 Kbits, higs will be mono, and rolled off, and other audible effects are likely to be obvious.

It seems unlikely to me that even with uncompressed music the difference in bit depth is causing the problem. It's my understanding that in blind tests bit depth and sampling rate above CD standard are not statistically distinguishable. To me that means that even if there are differences they are pretty minor. To the point that especially with different material, a person would probably never identify a difference in sound.

I'll take that as a "No, don't have a shred of perceptual/consumer data"
...and that arny's "dramatic improvements" are his subjectivist preference (like Ethan and other "Studiophiles") and thus a gospel fact that applies to all. Cool. Thanks.
Standing by for more strawman room conditions when the OP has source issues, in 3...2...1....

cheers,

AJ

p.s when I said "treat the source", I didn't mean after the fact

As AJ said, that is completely incorrect. Existence of large differences does not remove personal bias. Bias comes in whether there is an audible difference or not. DBTs help rule that out.

I didn't think of all people, it would be you Arny that would repeat this myth .

If you don't believe me, here is a good starting point: http://seanolive.blogspot.com/2009/0...o-product.html

"The Dishonesty of Sighted Listening Tests"

Here are the scores for sighted and blind testing of speakers which I am sure you agree also have very different sound (perhaps far more than many acoustic products):



You see how three out of four speakers changed roles in sighted vs blind?

Same can easily happen with room treatment. Put some impressive looking diffusers in a room and folks are immediately impressed and might thing the sound is better even if it has no changed perceptually or changed for the worse. Heck, put some foam on the wall and folks immediately think they are in a recording studio and be inclined to say the sound is better irrespective of the objective merit of the system and room. Misapplication of acoustic products can degrade the sound and AJ is right to ask for unbiased reporting on that. You can't dismiss that request on the basis of it doesn't matter because the differences are too large.

Indeed, if the differences are too large, then we better know what we are doing because we could also do big damage.


Me? Hiding with respect to blind test? No way. My track record here is excellent. I have been in more blind tests and conducted/created them than just about anyone here. One of the mandatory video codecs in Blu-ray came from my team due to two rounds of double blind testing. Sure, I argue for better measurements to augment the situation where we lack proper listening tests. But that doesn't mean I don't believe in application of blind testing. I wish I had 1000 times more blind tests to draw upon than we do now.

Specific to this example, I have twice sat through the Harman speaker double-blind testing lab. You should ask to see if they let you sit in one. I guarantee that you will change your views here. For now, here is another reference on the topic, from the chapter in Loudspeaker and Headphone Handbook written by Floyd Toole and Sean Olive:

In practice, the principal difficulty with subjective evaluations is to control what the listeners are responding to...It is well known, in subjective evaluations, that humans are susceptible to influences other than the parameter or device under test. We simply find it very difficult to ignore the evidence of brand, size, price, and so on.

...In loudspeaker evaluations, there is no argument that there are audible differences between products, and clearly audible differences traceable to interactions with programme and rooms. In comparisons of evaluations done in both blind and sighted conditions, it has been observed that listeners substantially altered their ratings of products when they were in view, following biases suggested by visual cues. "

The research here is pretty clear and conclusive Arny. You need to support people giving us objective evaluation of acoustic treatments, not sighted guesses and "art" as it was called in the other thread.

Correct me if I'm wrong, but your track record is zero in terms of doing DBTs that relate to your claims here, particularly related to the electronics that compose sources such as DACs .

Amir, sure you may have done a ton of DBTs, but AFAIK they related to other issues, like speakers and perceptual coders. While you paid others to do them, can you actually conduct one of your own that stands modest scrutiny?

I suspect we will never know.

Not really. I'm just tired of doing other people's homework for them.

Amir, thanks for making an unqualified claim that the technical differences due to room treatments are always comparable to those among good loudspeakers.

It is pretty well known that if you move different speakers around between different rooms, the resulting stereos sound more like the rooms that they are in, than the speakers they incorporate, given that the speakers are at least somewhat comparable.

I guess you are unaware of the size of technical problems due to rooms as compared to the technical problems due to speakers. They are frequently like an order of magnitude or more apart.

I made no statement in that regard. I simply corrected the myth that if there are large differences, DBTs are not needed. Whether the differences are due to speakers or acoustic products, it doesn't matter.


That has nothing to do with the topic of whether double blind tests are needed when differences are large or not. Or the need for non-biased tests of acoustic products.


The room dominates the speaker response in low frequencies. In transition region, the speaker and room matter. Above that, it is the speaker which dominates. So your generalization about me or the topic is not warranted.

Again, none of this changes the fact that bias impacts evaluation of acoustic products as well as it does anything else. But you can prove us wrong by conducting a test yourself, or showing us research that says otherwise. Do you have any Arny? AJ asked you and now I am asking.

So then there was no discernible context for that statement?

There was. That your justification that "Room treatments can effect such dramatic improvements that no DBTs are necessary" is without merit. "Dramatic improvements" do not compensate for personal bias. And that we need objective data here instead of guess work, assumptions, etc.

I agree with many of the things you say in general, but you sound very uneducated when you bad mouth the impact an improved room can have on sound.

So true, but I am having a hard time he doesn't know this. Maybe he has another point that we are missing? I really hope that is the case.

Prove it.

I did not limit the size of the benefit.

Do you wish to claim that no improvement can ever be so great that a DBT would not still be required?

How about an improvement from no sound, to good clean sound?

DBT still needed?

Not large enough? ;-)

You are making a mockery of yourself by calling Arny a subjectivist. I mean, seriously?

Again nitpicking. Why do you have to turn every thread into a soap opera by nitpicking side points that do not impact the main question asked. Do you agree or disagree room is the biggest source of distortion? If yes, please stop whatever you are doing.. yet again.

So even if I buy off on the above, which of course I don't, the speaker is more important if we manage to somehow listen to just high frequencies?

The problem with your claim about low versus high frequencies is that rooms are often highly reflective of high frequencies, and those reflections can vastly reduce things like clarity and detail.

So, in many rooms the room dominates over all sound quality in both the low and high frequency ranges.

I thus fearlessly say that: Other than the low and high frequency ranges, rooms don't matter. ;-)

One purpose that Amir's nitpicking serves is to distract people from serious questions that he doesn't want to answer, such as the question above about his alleged vast experience with DBTs of everything.

Trust me, DBTs of speakers are a whole 'nuther thing from DBTs of DACs or good SS amps. ;-)

I'l leave it to the reader to figure out who around here has done a lot of both.

I did. I showed the research that when substantial differences exist such as in speakers, bias was still a significant factor.


Correct. In double blind tests at Harman, I sat through an evaluation of Martin Logan speaker against a JBL speaker with horn. Let's agree that speaker technology does not get any more different than these two. Sighted, a lot of folks love that ML speaker. Put them behind the curtain and no one hardly votes for the ML. I know I did not in two rounds. Was hard to imagine that the ML sounded that bad!


You are missing the nature of the test and data being asked about. No one is saying that you need a DBT to know there is a difference. We are accepting that as the premise. The data being asked about is whether subjectively but without sighted bias, various room treatments improve the sound. The fact that they make a change is not in dispute (although many acoustic products fall in that category not making enough change to be audible). Accepting that the difference exists, we need to quantify if it is for the better or worse.

To wit, if I showed some some 703 fiberglass on a wall versus a diffuser, don't you think it impacts their evaluation of what they are hearing? Compare these two:



And a panel made from 709:



I guarantee you that many people would be biased to say the RPG panel sounds better. We need to remove that bias. You know that.

What's ironic is that the nature of the listening room can have dramatic effects on people's perceptions of source material.

Compared to JN, I may be a bit of a subjectivist, BTW.

He gets hyper about math, while it takes real audible differences to get a rise out of me. Not that I don't respect math or know a little bit (read significant post graduate work) about it. I've just spent too much time applying math to audio to get riled up about things that other people like to spend their whole lives worrying about.

According to the dictionary definition of subjectivist, I am one. Its only the weird high end audio definition of subjectivist that throws me out of that pool.

Yep, seriously.
Read it again as slowly and as many times as you need to. I'll do my best help if you still can't understand it.

cheers,

AJ

The research is all fine and good, but irrelevant to what I said (in context).

Thanks again Amir for falling into a trap I didn't even consciously set. It seems like you roam about just looking for holes to fall into! ;-)

'room 'treatments' is too vague of a term in the context of your statement.

some people incorrectly consider their bookshelves or other random room furnishings, 'diffusers' ... or thin porous absorbers that merely attenuate the HF band of the specular region as proper treatments to attenuate broadband high-gain indirect specular reflections...

and many blindly apply 'treatments' without so much as measuring the acoustical space to identify whether an issue even exists in the first place...

http://www.realtraps.com/customers.htm

--Ethan

AJ's universe is not the same as we live in. Obviously.

I find it amusing that she is so persistent in giving us the impression that room treatment of any kind is the work of the devil, and at the same time she is sooooo keen to bring up Toole and how wall reflections creates all kinds of audio "goodness", how she despite the "padded cell" approach etc. etc. etc., but in the end, if you call her cards, you'll find that she has has opted for the one speaker design that sacrifice soo much just to lower the room contribution -*especially* side wall reflections. Room treatment...Go figure

Typically, no, the acoustic sources are. Atypically, sure certainly could be.
You really ought to read and understand what the only guy I know of, Dr Toole, found in consumer living room environments. When you do, fill arny in too. Ethans a lost hope. Sells the stuff.


Schroeder is typically 200-300hz. Not very high at all.
Now about the OP's source problems...definitely a case for the mindlessly robotic knee jerk "room treatments!!!" if I ever saw a such a case. It's like an elixir, fixes everything, even his source player!! Very cool, these gauze/bandaids.

cheers,

AJ

AJ is not really badmouthing the impact of acoustic treatment, he's badmouthing me specifically. Where's that face palm smiley when you need it?

BTW, here's our guy AJ:

http://www.stereophile.com/content/soundfield-audio-0

I can just imagine what his system sounds like.

--Ethan

stuck living in the Flatland that is the frequency-domain. oblivious to the time-domain world/universe.

Nice.
Ok cool, so now I can list my customer/listener raves and earwitness accounts under "perceptual studies". Sweet, I'm legit now....

cheers,

AJ

What you said was very clear: that non-biased evaluation of acoustic products is not needed. That is just wrong. People are biased and assumptions are proven wrong time and time again. I see localhost posting here. I like the quotes from Dr. Toole he just post in the parallel thread. hd_newbie would do well to read them: http://www.avsforum.com/avs-vb/showt...8#post21817738


Thanks for constantly making these discussions personal Arny .

She's built her own universe where physics and psychoacoustics works the way she beleaves. Once you go dipole, you're all set. Or actually, you can also go KEF coax with active JBL (was it?) and you'll be good to go in your tiled livingroom.

Yeah right .