Loudspeaker Measurements

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Phoenix

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Re: Loudspeaker Measurements
« Reply #20 on: 26 May 2011, 07:40 pm »

The theory is that speakers which exhibit these measurements sound better in most rooms because the POWER response is even through-out the room. All, rooms have serious reflection and room node issues and a speaker that has a good on and off axis response will sound better because any reflected energy has a tonal balance close to the on axis frequency response.

That’s the theory – time to listen! :thumb:

james

Hi James!
You hit the nail on the head! And I agree that only the final listening test - after inspecting the measurements :wink: - will tell the complete truth about any speaker.

Do you have any clue why PMC doesn't release measurements? I'm asking because I'm planning to buy new speakers within the next year or so and the fact8 is a big temptation, however with measurements it would be an instant buy I guess...


James Tanner

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Re: Loudspeaker Measurements
« Reply #21 on: 26 May 2011, 07:52 pm »
Hi James!
You hit the nail on the head! And I agree that only the final listening test - after inspecting the measurements :wink: - will tell the complete truth about any speaker.

Do you have any clue why PMC doesn't release measurements? I'm asking because I'm planning to buy new speakers within the next year or so and the fact8 is a big temptation, however with measurements it would be an instant buy I guess...

Sorry I don't,  but my guess is that they feel measurements do not really tell the whole story. The graphs can be manipulated and massaged in the direction that reinforces what the target market expects to see?

james

Diamond Dog

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Re: Loudspeaker Measurements
« Reply #22 on: 26 May 2011, 09:13 pm »
 I think that if you are technically-inclined, being awash in test data may be reassuring when making a purchase decision and some firms will exploit that when they are marketing a product, just as some will base their marketing on for example, prestige ( say - putting stickers on their packaging which say " You Have Joined The Elite " ). That being said, when the rubber hits the road more people are going to base their decision on their ears than on test data because once outside of the hothouse environment that is the lab / chamber ( or forums like AC for that matter ), specs quickly lose their lustre when confronted with real-world situations involving interaction with the room and the existing gear and the much-vaunted synergy. I would go as far as to say that as many or more speakers are sold based on their appearance as on their sterling spec sheets and accompanying reams of test data. A pretty veneer finish will sell more speakers than a pretty directivity plot graph.

Trust your ears. They are amazingly sophisticated and will separate the wheat from the chaff pretty quickly given the chance. As to numbers which can easily be massaged to suit a predetermined narrative, a wise man once said " there are lies, damned lies, and then there are statistics..."
Now go listen to some music because life is short but music makes it sweet. :D

D.D.
 
« Last Edit: 27 May 2011, 01:15 am by Diamond Dog »

Phoenix

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Re: Loudspeaker Measurements
« Reply #23 on: 27 May 2011, 07:29 am »
Hi D.D.!

I'm not technically-inclined, in fact I'm playing the piano very emotionally.  :wink:

Most professionals will tell you that you can't trust your ears, therefore the measurements are a basic need to evaluate a speaker correctly.
Of course you can say that you only evaluate with your ears. But then, who tells you that the sound is right and not a coloured sound that you are used to or which you like because of personal taste?

A speaker should reproduce. Bryston amps reproduce - and that's good. They are well engineered and then carefully finetuned by ear because not everything can be measured. I doubt that James would say: "Oh, let's lower the range between 1000 and 2000 Hz about 2 dB because it sounds a bit nicer...!" That may be the case but it's not right!

So first of all a speaker has to show good measurements and then must be finetuned by ear and if you still don't like the sound, either your listening room is very bad or your personal taste doesn't like the truth.

And look at the experiment James wrote about. There is a scientific verifiable connection between perceived sound and measurements. They won't tell everything but measurements will tell at least 80 % about a performance of a speaker.

The argument that the measurements are taken in an anechoic chamber doesn't count. A speaker which does everything right in an anechoic chamber isn't suddenly wrong in your listening room. The better it performs in the chamber, the better it is your room.

There are many speakers out there which are sounded, not well engineered and simply not worth the money. They don't sound right. People are free to buy them if they like. But this has nothing to do with reproducing the recorded event in the best possible way as the recording engineer and perhaps the artist have intended.

James Tanner

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Re: Loudspeaker Measurements
« Reply #24 on: 27 May 2011, 11:50 am »
OK - lets throw into the discussion what your thoughts are on the materials used in the drivers themselves. 

Will this difference show up on the measurements of the speakers or for example will you hear Paper or Mylar or Ceramic as opposed to Metal etc. and can that be measured :scratch:

james

dflee

Re: Loudspeaker Measurements
« Reply #25 on: 27 May 2011, 12:09 pm »
Phoenix
Please enlighten me a little here. Are you saying you would rather listen to speakers you don't enjoy but know they are specked out perfectly than one that isn't but sounds better to you? I'm sorry but my hearing is my hearing and if I don't hear or prefer a certain type of sound I'm definitely not going to try and change just to be right with specifications. Life (and money) is too short for that.

Later
Don

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Re: Loudspeaker Measurements
« Reply #26 on: 27 May 2011, 12:15 pm »
Hi

I think sometimes a person's preference may not fall in line with product that by all standard measurements performs better or measures more linear.  Some people do not necessarily like to hear exactly what is passing through. I think that explains what some refer to as musicality and why there is so much difference of opinion for 'best sound at the show' :scratch:

James
« Last Edit: 27 May 2011, 02:59 pm by James Tanner »

Diamond Dog

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Re: Loudspeaker Measurements
« Reply #27 on: 27 May 2011, 01:02 pm »
Phoenix : Your position is so self-contradictory that it makes my head spin. You say that we can't trust our own ears and that we shouldn't buy speakers which we think sound good, only those which in theory should sound "right" based on scientific data. This is madness, pure and simple.

So first of all a speaker has to show good measurements and then must be finetuned by ear

So the human ear is the ultimate arbiter of what sounds good? Make up your mind, Phoenix.

if you still don't like the sound, either your listening room is very bad or your personal taste doesn't like the truth.
Outside of the laboratory, all rooms are bad. They all interact with the speakers  ( we try to correct for this ) and for that matter, so do the the cables, the other components, the flooring, the drapes, the furniture and so does my wife as she walks in front of the speakers as I try to enjoy the new Blackfield album I just got. Once the speaker leaves the controlled environment and gets plunked down in the real world, the numbers which led you to purchase them over those Fact 8's you liked ( but wouldn't buy because PMC wouldn't supply you with data to assure you that it was indeed OK to like them ) don't sound the same. You are puzzled by this no doubt because the data says that they should sound good.
As to personal taste, I'm not even going to go there...

The argument that the measurements are taken in an anechoic chamber doesn't count. A speaker which does everything right in an anechoic chamber isn't suddenly wrong in your listening room.

It isn't suddenly "right" either.

It comes down to this. This is way too subjective a topic with too many variables to be applying blanket statements to and declaring them to be "Truth". If you would pass up owning a pair of speakers which produce music which stirs your soul because they aren't accompanied by sufficient test data to reassure you that they would be "right", that's your lookout. If test data and graphs are what makes your pocket protector palpitate, I think your Neumans should suit. But to base a decision on data alone without even hearing a set of speakers makes as little sense to me as buying speakers solely because they are finished in Hubba Hubba wood or because they have tweeters made of pure Unobtainium  or because they are expensive enough to allow the manufacturer to sponsor a race team ( saw that last night on a TV at the gym. "So why did my Diamonds cost so much $$$???" ). So I trust my ears.
But that`s just my opinion...and I could be wrong. :wink:

Now go listen to some music. Perhaps this:                   http://www.youtube.com/watch?v=2IlHgbOWj4o&playnext=1&list=PL226DC4416B6A6870


D.D.

Afterthought:
Isn't it ironic that studio monitors which are so "right" technically speaking have been used to unleash so much dreadfully recorded, mixed and mastered music on un unsuspecting world. If they are so exquisitely accurate, so sonically perfect, how can that possibly happen ? Oh wait....








dogbait

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Re: Loudspeaker Measurements
« Reply #28 on: 27 May 2011, 01:17 pm »
Quote from: Diamond Dog
Afterthought:
Isn't it ironic that studio monitors which are so "right" technically speaking have been used to unleash so much dreadfully recorded, mixed and mastered music on un unsuspecting world. If they are so exquisitely accurate, so sonically perfect, how can that possibly happen ? Oh wait....

I wish I could upvote this! It's definitely something I've wondered. How studios can spend £100k+ on monitors and amps and then produce such badly mastered music. Poorly mastered tracks not only measure poorly (spectral analysis and waveform) but they sound terrible too...

PRELUDE

Re: Loudspeaker Measurements
« Reply #29 on: 27 May 2011, 01:36 pm »
YG ACOUSTICS claims as [THE BEST SPEAKER] and let say they measurements on these speakers is the best ever. If I order this speaker today at $120,000 would they agree to come to my house and do the measurments again to see if it would mach with the original one or no?
Oh,of course I would pay the flight,meal and hotel with no problem.
I heard it few times and talk to the people in the room and not so many of them were impressed.

Danny Richie

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Re: Loudspeaker Measurements
« Reply #30 on: 27 May 2011, 01:48 pm »
FYI, I have measured quite a few of those "studio monitors" that are supposed to be so accurate, and most of them are not. The last Mackie's that I measured were barely withing +/-3db and clearly had issues. Some Behringers that I measured recently had good on axis and off axis response but had a long list of other problems.

Let me just touch on a few problems that drastically alter the sound but don't show up on the measurements.

1. The materials used in the drivers have a pretty big effect. Metal cones usually have a little ring to them even if the crossover has addressed most of it.
2. Some woofer frames can even ring at certain wavelengths.
3. Capacitors have a huge effect. And the measurements never show the smearing effect of cheap caps.
4. Iron core inductors can really muck the sound up. There is even a pretty noticeable difference in the Chinese made recycled Copper inductors compared to the really good OFC air core inductors made in North America.
5. Resister quality.
6. Wire quality.
7. Cabinet resonances. This can be measured but not often. Even if you do see one it might be a random placement. You really have to take lots of measurements all over the cabinet to see problem areas.
« Last Edit: 30 May 2011, 03:38 am by Danny »

Phoenix

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Re: Loudspeaker Measurements
« Reply #31 on: 29 May 2011, 09:53 am »
Hi D.D.!

First of all, I don't want to impose my believes or opinions about this topic on anyone. So there's no need to say that I'm lost in madness or to imply that I'm a robotic being without feeling. Anyway, it's a little bit difficult to argue in a foreign language and make ones point clear. Therefore I do not further elaborate my opinions as it seems that you won't take any serious attempt to understand my point of view (e.g. you completely ignore the facts of James' experiment or why an amp has to have a flat frequency response and a speaker suddenly doesn't have to show such "good" measurements...).

Other in this thread do understand.
I don't say that measurements are the holy grail. But they are the base for evaluating a speaker since there are (at least for a sound engineer) well known basic and irrevocable facts which influence sound quality und sound reproduction - everything that goes beyond is for the ear. And this is NOT a proof that the ear/brain is superior to measurements and free from error.

Danny's list shows pretty well that not everything can be measured. That's why you still have to listen, and change your design if necessary. But changing a capacitor doesn't change basic things like the directivity of your speaker.

Another thing: I'm sure that A LOT of emotional and good recordings you own are made with your so called "emotionless" K+H, Neumann, etc. studio monitors or microphones. THAT is contradiction!



@dogbait:

I guess that there are two reasons for this phenomenon:

Firstly, the sound engineer has a bad monitor (perhaps bought only based on hearing evaluation...  :icon_twisted: ) or
secondly, the sound engineer has to do what marketing wants (e.g. loudness war).




James Tanner

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Re: Loudspeaker Measurements
« Reply #32 on: 29 May 2011, 10:25 am »
Hi D.D.!

First of all, I don't want to impose my believes or opinions about this topic on anyone. So there's no need to say that I'm lost in madness or to imply that I'm a robotic being without feeling. Anyway, it's a little bit difficult to argue in a foreign language and make ones point clear. Therefore I do not further elaborate my opinions as it seems that you won't take any serious attempt to understand my point of view (e.g. you completely ignore the facts of James' experiment or why an amp has to have a flat frequency response and a speaker suddenly doesn't have to show such "good" measurements...).

Other in this thread do understand.
I don't say that measurements are the holy grail. But they are the base for evaluating a speaker since there are (at least for a sound engineer) well known basic and irrevocable facts which influence sound quality und sound reproduction - everything that goes beyond is for the ear. And this is NOT a proof that the ear/brain is superior to measurements and free from error.

Danny's list shows pretty well that not everything can be measured. That's why you still have to listen, and change your design if necessary. But changing a capacitor doesn't change basic things like the directivity of your speaker.

Another thing: I'm sure that A LOT of emotional and good recordings you own are made with your so called "emotionless" K+H, Neumann, etc. studio monitors or microphones. THAT is contradiction!



@dogbait:

I guess that there are two reasons for this phenomenon:

Firstly, the sound engineer has a bad monitor (perhaps bought only based on hearing evaluation...  :icon_twisted: ) or
secondly, the sound engineer has to do what marketing wants (e.g. loudness war).

Hi Phoenix,

The sound engineer is a really good point.  Because we sell a lot of Bryston amps into the studio market I can tell you I am amazed sometimes that the recordings come out sounding as good as they do given the signal path some of the recordings go through.  I do have a theory on that.

james

Diamond Dog

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Re: Loudspeaker Measurements
« Reply #33 on: 30 May 2011, 12:50 am »
" Well, sir, here's to plain speaking and clear understanding."
                Sydney Greenstreet as Kaspar Gutman in The Maltese Falcon

Phoenix :  You appear to have either misinterpreted my earlier comments or are twisting them to suit your narrative. In the interest of clear understanding, allow me to speak plainly.
First of all, I don't want to impose my believes or opinions about this topic on anyone.
Go re-read your initial post and see if you don't want to walk this statement back.

... there's no need to say that I'm lost in madness or to imply that I'm a robotic being without feeling.
Now go re-read my post. What I said was this:
You say that we can't trust our own ears and that we shouldn't buy speakers which we think sound good, only those which in theory should sound "right" based on scientific data. This is madness, pure and simple.

As you can see, it's the opinion you had expressed which I described as madness. At no point did I state or imply that you are "lost in madness". The state of your mental health is between you, your family and your health care provider. While we're at it, I have no idea as to whether or not you are "a robotic being without feeling". What I was actually implying was that your slavish devotion to stats and test data over real-world experience was giving you the appearance of what we in North America refer to as a "poindexter" ( Google it ). Just so that we're clear.
Therefore I do not further elaborate my opinions as it seems that you won't take any serious attempt to understand my point of view (e.g. you completely ignore the facts of James' experiment or why an amp has to have a flat frequency response and a speaker suddenly doesn't have to show such "good" measurements...).
Other in this thread do understand.
Everyone here has the right to express their opinion. If someone's opinion fails to mesh with yours, it doesn't necessarily stem from ignorance. I understand the view you are expounding- I just don't agree with it. I will say that as you continue to post, your opinion does seem to be evolving into something perhaps a bit more moderate that we can perhaps all agree with at some point. That's good - shows potential for personal growth on your part. Run with it.
Another thing: I'm sure that A LOT of emotional and good recordings you own are made with your so called "emotionless" K+H, Neumann, etc. studio monitors or microphones. THAT is contradiction!
And you know full well that some of them were also made using PMC's. And some of those recordings sound like crap, too. So where's the contradiction ? Nobody's criticizing your Neumanns, Phoenix. Stop being such a fanboy-you're embarassing yourself.

D.D. 

Phoenix

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Re: Loudspeaker Measurements
« Reply #34 on: 30 May 2011, 03:53 pm »
@ D.D.

Maybe you haven't displeased me the direct way but things like "Make up your mind!", "This is madness, pure and simple.", "You are puzzled...", "Now go listen to some music." (together with a link to "She Blinded me With Science"), "fan-boy", etc. are by no way a basis for an objective discussion - and your last post didn't make it better. So I will not comment on anything within your last accumulation of insolences.

You can think and argue what you want - it is very clear that your "between the lines"-writing style tries to undermine my competence (at least that litte which I do have) and presenting me as someone who is more concerned with technical data than music. That's not true and therefore I won't take back any statement I've made.

Besides that, you don't respond to simple and well known facts I or other present (you still haven't said anything on James' experiment...), because they don't fit in your (mis)belief that a speaker is a mystical thing which can't be understood by science and only your ear can hear "the truth". But the real truth is: A speaker can be measured and the measurements cohere directly with the sound reproduction quality. Without good measurements a speaker will never ever sound right. With good measurements it is most likely that it will sound right, even in a bad room. And a good measured speaker will almost always sound more right than a bad measured speaker within the same environment.

Instead of trying to understand this basic concept you concentrate on bullying me. That's annoying.

And so there's nothing more to say but to recommend reading this book before posting again:

http://www.amazon.com/Loudspeakers-recording-reproduction-Philip-Newell/dp/0240520149/ref=sr_1_4?s=books&ie=UTF8&qid=1306768770&sr=1-4

srb

Re: Loudspeaker Measurements
« Reply #35 on: 30 May 2011, 04:55 pm »
I'm sure in the end, measurments can account for differences between loudspeakers, but some of them are either not available or if they are, not necessarily interpretable by the average audio enthisiast.
 
While on and off-axis frequency response and impedance graphs, sensitivity, etc. paint a broad picture of a speaker's sound, the fact is that there are tone and timbre differences in voice and instruments that exist between similarly spec'd speakers.
 
Even speakers with similar spectral analysis and waterfall plots can still exhibit tone and timbre differences, more so than tone and timbre differences between amplifiers.  Multi-driver speakers also exhibit differences in preceived tonality depending on phase relationships between drivers.
 
Add in all sorts of other variables including cabinet and driver resonances previously mentioned, and it is easy to understand why speaker designers often re-tweak designs that looked so good on paper.
 
If you compare two different $10K, $50K or $100K speakers side by side, most people can discern different tonality depending on program material.  I wouldn't necessarily be able to say which one was "better" or more accurate, or even which one I for sure liked the best, but the fact remains that there would still be some audible differences beyond any presented specifications.
 
Steve

James Tanner

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Re: Loudspeaker Measurements
« Reply #36 on: 30 May 2011, 05:25 pm »
I have decided I am going to build an 3- way Active speaker for myself with all the NRC measurements intact and see what I think.

james

PRELUDE

Re: Loudspeaker Measurements
« Reply #37 on: 30 May 2011, 07:03 pm »
I have decided I am going to build an 3- way Active speaker for myself with all the NRC measurements intact and see what I think.

james
Now you are taking about James and get ready for a lot of surprises. :thumb: :thumb: :thumb:

vegasdave

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Re: Loudspeaker Measurements
« Reply #38 on: 31 May 2011, 12:25 am »
I have decided I am going to build an 3- way Active speaker for myself with all the NRC measurements intact and see what I think.

james


Seriously?

vegasdave

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Re: Loudspeaker Measurements
« Reply #39 on: 31 May 2011, 12:25 am »
Hi Phoenix,

The sound engineer is a really good point.  Because we sell a lot of Bryston amps into the studio market I can tell you I am amazed sometimes that the recordings come out sounding as good as they do given the signal path some of the recordings go through.  I do have a theory on that.

james



Cool! What is your theory, please...:D