Loudspeaker Myths: Separating the Scientific Facts from Science Fiction

[crossedover]

Btw, labeling me as a 'forum troll idiot that just begs for attention' is such a classy move, Gene. Or is that Clint 'evolution? it's a hoax!' DeBoer's doing? Between this and that shadowbanning episode, I have to wonder....

That in it self is trolling

 

[krabapple]

Sean Olive did not publicly comment on this article as far as I am aware. He did give me some feedback initially and I made some changes accordingly. I have immense respect for Dr. Toole and Dr Sean Olive but it doesn't mean I always agree with their research or how Harman decides to trickle that research into their actual products.

Sean commented in the thread that was about your previous critiques of DBTs. So as I said, he has 'contributed to forum threads'.

So, are you saying that the DBT sections were *not* vetted by Dr. Toole either? And that Dr. Olive hadn't seen the final version of them either?

What I say may not be very popular with some manufacturers but I base in on my 20+ years of experience in this field as well as my scientific training as an audio engineer that spent years in the telecom industry setting up controlled listening tests and also contributing to standards bodies and dealing with the politics therein. It is no coincidence that every speaker company that cherishes the blind test always wins their own shootouts. Though I notice that rhetoric has been wining down in the last few years since I've been writing about it. I rarely see loudspeaker companies use the term "similarly good" these days Now they often claim they use blind testing to better understand perceptual differences product upgrades in their own products more so than to compare to other brands.

What companies, what shootouts, what use of 'similarly good' are you referring to? Links please.

 

[krabapple]

That in it self is trolling

Fascinating definition of trolling.

I did, in fact, get into it with Clint over evolution. (I'm a biologist by training)
I was, in fact, shadowbanned. Some nice people here got that reversed.
I have, in fact, engaged Gene before on this exact topic: his overgeneralized complaints about DBTs. Sean Olive chimed in on that thread too.
My name is now, in fact, accompanied by the description "a forum troll that begs for attention'


In fact, I don't post much to Audioholics; odd behavior for someone 'begging for attention' here, don't you think?

You, who've only been here since January?

 

[3db]

Excellent feedback guys. Keep it coming. This was a pretty big effort as it was really meant to be a 5-10 min video interview with Hugo and it just blew up. The video is completely separate content from the article since we don't script our videos. Once the camera starts rolling, watch out! LOL.

I want to say thanks for the write up Gene before I keep asking my questions just so you know that I appreciate the effort. It was a lot of work. I'm merely trying to understand this first reflection point.

What I understood form reading the article isthat the NRC's measuring is missing the first reflection point in its measurements which I would think is a good thing because its not taking into account the room's response.

 

[gene]

Btw, labeling me as a 'forum troll idiot that just begs for attention' is such a classy move, Gene. Or is that Clint 'evolution? it's a hoax!' DeBoer's doing? Between this and that shadowbanning episode, I have to wonder....

You earned that reputation based on the forum community giving it to you. If you don't like it, maybe you need to change your tone in your posts. You bring some valid points in this thread but you're tact is a bit lacking. It's possible you need a little vacation from the forum to cool your head. It's only a hobby my friend. We aren't solving world hunger or climate change.

 

[gene]

Fascinating definition of trolling.

I did, in fact, get into it with Clint over evolution. (I'm a biologist by training)
I was, in fact, shadowbanned. Some nice people here got that reversed.
I have, in fact, engaged Gene before on this exact topic: his overgeneralized complaints about DBTs. Sean Olive chimed in on that thread too.
My name is now, in fact, accompanied by the description "a forum troll that begs for attention'


In fact, I don't post much to Audioholics; odd behavior for someone 'begging for attention' here, don't you think?

You, who've only been here since January?

I apologize about the evolution thing from many years ago. I didn't even know that BS religious movement of ID until that came up in our threads. What a bastardization of science that is! I'm not sure about the reputation points you earned. I don't police that. I let our mods do it.

 

[gene]

Sean commented in the thread that was about your previous critiques of DBTs. So as I said, he has 'contributed to forum threads'.

So, are you saying that the DBT sections were *not* vetted by Dr. Toole either? And that Dr. Olive hadn't seen the final version of them either?





What companies, what shootouts, what use of 'similarly good' are you referring to? Links please.

Dr. Toole read the entire article and redlined it and contributed in many areas. He may not agree with every point I made but overall he liked it. The fact that he still converses with me and ALWAYS offers his editing services at no charge speaks volumes.

I prefer to keep brand names out to not show any biases or negative ill towards anyone. I discussed a few brands in the video but let's leave it at that. You can look at all of the companies that promote NRC and DBT and just apply my discussion towards them as it fits their story. That being said, I'm getting a lot of great private feedback from speaker manufacturers thanking me for writing this article and doing the video. Sure it hits some nerves with some, but it also raises valid points and in my hope will help push the science further while keeping the marketing and political nonsense to a minimum.

 

[krabapple]

You earned that reputation based on the forum community giving it to you. If you don't like it, maybe you need to change your tone in your posts. You bring some valid points in this thread but you're tact is a bit lacking. It's possible you need a little vacation from the forum to cool your head. It's only a hobby my friend. We aren't solving world hunger or climate change.

There's no transparent tally of total reds/green points that I can find, so one has to wonder who and how many in the 'forum community' are responsible for my relatively recent descent to 'forum troll idiot*' status. Right now, what I can see, it's 3:2 green:red for me. Are some members of the community more equal than others when it comes to voting, like in Animal Farm?


Hmm, and 'Tact is a bit lacking' says the man who called me a 'forum illiterate' back in October, when I commented on an article where he wrote 'Objectivists can go suck it'.


As for a vacation, really, have you seen how rarely I post here?


(* and really, a category called "forum troll idiot that just begs for attention" reads kind of childish in the first place, don't you think? Who came up with that gem?)

 

[Pyrrho]

In my opinion, Double-Blind tests are to test the reviewer, not the speakers. People who claim that is the only way to do speaker testing are almost always doing so because they don't believe reviewers can tell the difference between products and they want them to prove themselves.
...

Yes, obviously. If people were reliable, then there would be no need of double-blind testing at all. But people get everything wrong. People often talk about medicine in connection with this (as, indeed, they should) but my favorite example is with wine:

http://www.nytimes.com/2008/01/15/world/americas/15iht-wine.1.9221093.html?_r=0

If someone believes the wine is more expensive, they experience it as being better. Read the article.

 

[Swerd]

… I'm merely trying to understand this first reflection point.

What I understood form reading the article is that the NRC's measuring is missing the first reflection point in its measurements which I would think is a good thing because its not taking into account the room's response.

You do understand this question. The NRC's measurements capture the sound of the speaker while avoiding sound or coloration contributed by room walls, ceilings, and floors. That's one of the primary reasons they went to the expense of building their anechoic room. Why bother with publishing frequency response curves if they are so colored by room responses that they are useless for comparisons?

Note that measurements taken in a anechoic room can still differ from those taken in a normal room using "quasi-anechoic" software settings. The "quasi-anechoic" measurement will still show a large response dip somewhere between about 80 and 150 Hz. Known as "floor bounce", this is caused by cancellation between the sound going directly to the microphone and the sound that reflects off the floor and arrives at the mike with a slight delay. The time gate can eliminate reflections from walls and ceiling, but not floor reflections that occur between the speaker and the test mike.

Most anyone I know who can do speaker measurements regards the NRC results as the gold standard. If your own measurements differ from the NRC's, then you have some room for improvement. If your results look similar, then you can smile with satisfaction.

 

[sawzalot]

Fascinating definition of trolling.

In fact, I don't post much to Audioholics; odd behavior for someone 'begging for attention' here, don't you think?

You, who've only been here since January?

I dont want to fuel the nonsense which could typically derail an otherwise awesome thread but I do have to agree with krabby here.

 

[gene]

Misuderstood your Question

"Editorial Note About the NRC Measurements
The listening window is a combination of 0, +/- 15 vertical, and +/- 15 and 30 horizontal (the NRC measurements used 15 deg increments, Harman uses 10 deg). This describes the average direct sound arriving at a group of listeners. It does not include the first reflections.

Sound power is a weighted average of all the curves, leading to an estimate of the total sound energy radiated over a 360 deg sphere. "

Wouldn't the first reflection points be considered as part of the room's response to the speaker's stimuli thus measuring the room's interaction rather than the loudspeaker itself?


​

Sorry I totally misunderstood what you were asking. Let me try again I also updated the article to be more clear on this topic.

Listening Window Response, Sound Power and Spinorama by Dr. Floyd Toole
The listening window is a combination of 0, +/- 15 vertical, and +/- 15 and 30 horizontal measurements (the NRC measurements used 15 deg increments, Harman uses 10 deg). This describes the average direct sound arriving at a group of listeners. This is one component of the full set of measurements, called the spinorama. However the listening window response does NOT include the first reflections.

The spinorama is a 360 deg set of 70 frequency response measurements (10 deg increments on horizontal and vertical axes) intended to capture the complete sound that is radiated into a room - and therefore which will arrive at a listener in that room. They are intended to allow us to estimate what happens in rooms. THESE measurements DO take first reflections into consideration which are the second loudest sounds to arrive at a listener.

We start with the on-axis frequency response which will be the first sound to arrive at a single listener in the sweet spot, at which the speaker should be aimed. The listening window is intended to be an estimate of the first sound to arrive at a group of listeners - in a good loudspeaker there is little difference between this and the on-axis response. Next, we look at the combined energy of the early reflections, estimated by knowing the angular ranges over which wall, ceiling and floor reflections occur - this curve is called the "early reflections" curve.

Then we estimate the total sound power, the energy radiated through a sphere surrounding the loudspeaker, by weighting the individual frequency responses and combining them (this is NOT the simple average of all the frequency responses that some mistakenly often claim).

So, out of it all we get estimates of the three principal classes of sounds arriving at listeners: direct, early reflected, and late reflected or reverberant. With this data it is possible to predict with good accuracy (a) the average steady-state room curve (above the transition frequency of course) measured in the listening area and (b) the subjective preference rating as determined in double-blind, positional-substitution listening tests. This assumes that the room is "typical" - not having aberrant acoustical treatment.
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[utopianemo]

Pretty much, yes. Blind methods can indicate whether the *reviewer* is being influenced by something beyond just the sound of the loudspeaker.


To me, that's really just another 'circle of confusion' to use Floyd Toole's term. Too many unknowns relying on each other.

Krabapple, these guys aren't practicing law. They're not operating on patients. They're writers, and they get paid to tell us their opinions on stuff. Look, I understand where you're coming from, and I agree with what I perceive to be your starting point(or at least the general starting point of people who tend to share your view). There has been a lot of abuse propagated by the world of audiophile journalism. Audiophile journalists have had an elitist approach, probably fed by advertising dollars. The search for ever better sound has almost become a search for transcendence. Adherents to this religion have left critical thinking aside and are freely open to delusion when it comes to all manner of "improvements", whether it be exotic cables or magic stones or whatever. They use flowery words to describe how a certain sound "feels", and recommend spending inordinate amounts of money on products that often provide minuscule improvements at very best.

It is this abuse that tends to form the foundation for your("your" I mean in the general, plural sense) sentiments. I respect that, it's just that my personal solution for that problem works better for me. I just don't read reviews by those types of people. For me, I find a Wikipedia-style of information gathering to be more helpful when choosing what products to buy than a strict empirical approach. For example, I'm looking to upgrade my speakers. For my budget and tastes, I've whittled it down to the ARX A2rx-c's or the Wharfedale Diamond 10.2's. I've read just about every review I could find online for these and their nearest siblings. The reviews for these products have tended to use descriptors I would use to describe speakers I want to own. The reviewers have compared them to other speakers I was interested in, and in doing so have fleshed out the characteristics of my proposed speakers versus those other speakers. Since neither of these brands are available in my area, the next step is going to be to try them out.

None of the reviews I read utilized ABX or any other type of blind testing, and it wouldn't have helped me one way or another if they'd had. I've read enough reviews to get a consistent general consensus as to the character of these speakers. I don't need to know whether any of these people could pick my proposed speakers out in a blind lineup; the rules of statistical probability tell me more about any one of these reviewers than a blind test could. That's how I test my reviewers. I don't agree that that amounts to a 'circle of confusion', but if my methods aren't useful to you, I can live with that. We all have to make up our minds one way or another; I just know what works for me.

 

[utopianemo]

Yes, obviously. If people were reliable, then there would be no need of double-blind testing at all. But people get everything wrong. People often talk about medicine in connection with this (as, indeed, they should) but my favorite example is with wine:

http://www.nytimes.com/2008/01/15/world/americas/15iht-wine.1.9221093.html?_r=0

If someone believes the wine is more expensive, they experience it as being better. Read the article.

Okay, I read the article. This was a study of 20 people; the researcher in charge explains part of his guess as to why the results came out how they did is that the "subjects were not very experienced".

The wine-related anecdote I prefer comes from Glynn Washington of the Snap Judgement podcast. When he was at University, he took a Psychology class where the professor started every lecture by inviting the students to the back of the room where he revealed a table full of wine, cheeses, and the like. He talked about the qualities of the wine and the food while the class imbibed and enjoyed themselves.
On the day of the final, he took them back to the table, and told them everything was as it had been in the beginning, and invited them to drink. When they tasted the wine, it was terrible! Each week he had secretly been exposing them to incrementally better wine, and on the day of the final he had given them the wine he had started with. Telling them they were the only ones who could choose who they were to become, he revealed a second table with the good stuff.

I don't put a whole lot of stock in anybody telling me about the qualities of something unless they have experience. I wouldn't trust 20 random non-experts to inform me what wine tasted better, nor would I trust 20 non-experts to tell me which speaker they liked best, blind or not. North Americans tend to have a bias towards excessive low and high-end frequencies anyway. Why would I put any stock in that?

With respect to actual reviewers, I read their comments and compare them with other comments. If they get weird, I find another reviewer. It's worked fine so far. I don't think it's reasonable or even sensible to expect reviewers, especially professional ones, to undergo that kind of testing. That might not work for you but I'm okay with that.

 

[jinjuku]

I don't put a whole lot of stock in anybody telling me about the qualities of something unless they have experience. I wouldn't trust 20 random non-experts to inform me what wine tasted better, nor would I trust 20 non-experts to tell me which speaker they liked best, blind or not. North Americans tend to have a bias towards excessive low and high-end frequencies anyway. Why would I put any stock in that?

What I would expect is that Wine companies that espouse the qualities of their vino to then be discernible across their target market: Anyone that drinks wine. In the manner they say it is.

I wouldn't trust someone just shooting from the hip and saying North Americans have a bias towards excessive low and high-end FR.

 

[jinjuku]

Fascinating definition of trolling.

I did, in fact, get into it with Clint over evolution. (I'm a biologist by training)
I was, in fact, shadowbanned. Some nice people here got that reversed.
I have, in fact, engaged Gene before on this exact topic: his overgeneralized complaints about DBTs. Sean Olive chimed in on that thread too.
My name is now, in fact, accompanied by the description "a forum troll that begs for attention'


In fact, I don't post much to Audioholics; odd behavior for someone 'begging for attention' here, don't you think?

You, who've only been here since January?

Krabbaple may be a bit gruff in his posting style. But IMO he presents well reasoned responses. I don't think one need be considerate of other peoples lack of topical knowledge. If I need to get schooled then I get schooled. I've more than once publicly thanked the person for the lesson, settled down, and put my listening ears on for all parties.

I'm of the camp of more in line of the claim and claimant is what is being tested. Not necessarily the speaker, cable, electronics.

 

[gene]

I just added this section which is open for debate of course.

Drawbacks in Running Mono Speaker Tests?

It is our understanding that Harman runs mono single speaker comparisons using positional substitution so that each time a speaker is switched, the competitor product is placed directly in the same location as the last speaker tested. This method is designed to remove the room and the stereo effect from the contest. According to Dr. Floyd Toole's research, a speaker that wins in mono ALWAYS win in stereo too.


Why not add the room and stereo effect to the contest? if that gives one speaker an advantage over another, does that not count in the contest? Is it fair to a speaker which has incorporated those elements into its design philosophy?


I would caution the reader that by running a single mono speaker test with the speaker placed in the center of the room will favor certain types of speakers and be unfavorable to other types of speakers based on their radiation pattern. This is why, in our opinion we think there is a lot of merit in properly setting up each pair of speakers per manufacturer guidelines in a room for extended listening sessions to truly understand its full potential of performance.

edit. fixed stereo/mono comment b/c I got my wires crossed

 

[zieglj01]

Thumbs-up for a good article

Thumps-up for the make-up artist

Thumbs-up for the set decoration - it would have been 2 thumbs-up,
except there was no speaker in front of Captain Kirk and the lighting
was a little weak.

As far as pro-reviews, I mainly only pay attention to the measurements,
because audio preference and sound is still subjective - I do not believe
in DBT speaker testing, and one reason for that is, because human mood
swings and the environment can effect that. In reality, how many people
most of the time listen to their speakers and systems, with their eyes
closed. I am also not a big fan of level matching, because I do want the
speakers to sound good at all levels - and I prefer to control the volume.

The so-called one perfect speaker is, the one that is close enough in sound
and sonic signature, with the imaging and sound-stage presentation, that
can/will captivate you for long term listening with your eyes open or closed.

 

[gene]

Thumbs-up for a good article

Thumps-up for the make-up artist

Thumbs-up for the set decoration - it would have been 2 thumbs-up,
except there was no speaker in front of Captain Kirk and the lighting
was a little weak.

As far as pro-reviews, I mainly only pay attention to the measurements,
because audio preference and sound is still subjective - I do not believe
in DBT speaker testing, and one reason for that is, because human mood
swings and the environment can effect that. In reality, how many people
most of the time listen to their speakers and systems, with their eyes
closed. I am also not a big fan of level matching, because I do want the
speakers to sound good at all levels - and I prefer to control the volume.

The so-called one perfect speaker is, the one that is close enough in sound
and sonic signature, with the imaging and sound-stage presentation, that
can/will captivate you for long term listening with your eyes open or closed.

These interviews are done in my theater room which is as dark as the Batcave, not at our HD video production studio. I admit Hugo and I are rank amateurs at shooting videos but we are trying to improve. Getting a lighting kit and ext mic for next interview to improve. thx.

 

[Steve81]

According to Dr. Floyd Toole's research, a speaker that wins in stereo will almost always win in mono too.

If nothing else, it would seem like testing a random stereo pair from a retailer would be a good quality control test, i.e. ensuring people are getting properly matched pairs instead of a pair that might have been manufactured a couple months apart and on opposite ends with respect to tolerances.