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Evidence-based Speaker Designs

Thomas savage

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People on this board miss represent the research imo

The reason Harman took that research project on was because it could help them sell speakers into a practical market space not audiophile market space or treated room market space.

If you have a heavily treated room and you are educated in room acoustics and maybe you have some software you don't need an expensive Harman speaker.

There's so much misapplied science here it boggles my mind.

The Harman search was all about selling speakers into home environments.

That's the dollar they were chasing, not ultimate performance if that was the case the enclosures would have been different and it all would have been different.
 

Thomas savage

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I'm not finished, point to another science where one single study has been held up as fact? That's not how science works if you want to look at science you can pretty much prove anything or try to prove anything science is a bunch of people trying to prove things it's a battle but eventually there's a consensus.

it's not and never has been one source of information held above all else without any challenge.


The harman research is a factor in audio science but it's not audio science.

Claiming otherwise is basically to form a religion around harman research.
 

QMuse

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I'm not finished, point to another science where one single study has been held up as fact? That's not how science works if you want to look at science you can pretty much prove anything or try to prove anything science is a bunch of people trying to prove things it's a battle but eventually there's a consensus.

it's not and never has been one source of information held above all else without any challenge.


The harman research is a factor in audio science but it's not audio science.

Claiming otherwise is basically to form a religion around harming research.

M8, I think you should retire for today while you're on top, because if you continue like this..
 

amirm

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People on this board miss represent the research imo

The reason Harman took that research project on was because it could help them sell speakers into a practical market space not audiophile market space or treated room market space.
Thomas, the research and its conclusions were reached while Dr. Toole and others worked at NRC. Canadian government had decided to help the local audio market to be more competitive so invested heavily in building an anechoic chamber and research lab around it. Dr. Toole's goal was to determine why people liked speakers and whether any common factors could be found. This is Dr. Toole's work history on LinkedIn:

1590172507662.png


As seen, he started at NRC in 1965 and was there for some 26 years before joining Harman. Many of Dr. Toole/Olive research papers are published under NRC title for example. It is remarkable how closely they read to current research published under Harman name. Here is good example I saved for another occasion:

Toole NRC.PNG


A number of Canadian speaker companies benefited from this research at NRC with PSB and Paradigm being prime examples.

Harman allowed the research to flourish, often funded by better sound for automotive systems that is a multibillion dollar business for Harman (they were sister groups for a long time).

Of course the final goal was what you said: enable designs of speakers that sound better to consumers and hence sound better.

While we discuss Harman research here almost exclusively, there are countless work that this research relies on from other sources. And just as well, many other researchers have built on it.

We may have put a tidier bow on the research than perhaps we should have. Our measurements of speakers I think is helping fill more of the puzzle. But the purpose of the research was rather pure and not aimed at helping Harman sell speakers.
 

Thomas savage

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Thomas, the research and its conclusions were reached while Dr. Toole and others worked at NRC. Canadian government had decided to help the local audio market to be more competitive so invested heavily in building an anechoic chamber. Dr. Toole's goal was to determine why people liked speakers and whether any common factors could be found. This is Dr. Toole's work history on LinkedIn:

View attachment 64827

As seen, he started at NRC in 1965 and was there for some 26 years before joining Harman. Many of Dr. Toole/Olive research papers are published under NRC title for example. It is remarkable how closely they read to current research published under Harman name. Here is good example I saved for another occasion:

View attachment 64832

A number of Canadian speaker companies benefited from this research at NRC with PSB and Paradigm being prime examples.

Harman allowed the research to flourish, often funded by better sound for automotive systems that is a multibillion dollar business for Harman (they were sister groups for a long time).

Of course the final goal was what you said: enable designs of speakers that sound better to consumers and hence sound better.

While we discuss Harman research here almost exclusively, there are countless work that this research relies on from other sources. And just as well, many other researchers have built on it.

We may have put a tidier bow on the research than perhaps we should have. Our measurements of speakers I think is helping fill more of the puzzle. But the purpose of the research was rather pure and not aimed at helping Harman sell speakers.
Yeah but it was in its infancy then and it wasn't challenged.

Tell me this what other area in science would you take one research paper and ignore everything else even if that arean of research was in this case audio so no one else has bothered basically.

No I'm not saying the Harman research isn't right but it's not been thoroughly investigated that's not their fault but it is however an inconvenient truth.

it exists as an island and you're and defaqto our reliance on it serves only to reinforce that.

In this context you can blame people for questioning things, and you can't blame people for questioning your absolute belief.
 

Thomas savage

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in this forum the over alliance on one man's book and one tiny tiny tiny example of research in the Sean olive and Toole Harman , Canadian originated research is a huge weakness.

It's undeniable . Again it might hit the jackpot it might be perfectly right but it's not science. The lack of competing argument and further exploration makes it belief.

I would say you had a belief moment when you went to Harman and you had the experience that broke your subjectivity that's a belief moment it's not a science moment. You need to think about why you you used the word science in audio science review. Evangelical moments of Discovery aren't science even if they are correct.
 

QMuse

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IMHO some parts of T&O research maybe needs to be researched in more detail, for example potential improtance of horizontal directivity, IMD, ..
But it should be done in an equally systematic way they did their research and that is really hard to acomplish.
 

Thomas savage

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It's not a criticism of Toole and olive if anything is a criticism of competing theories. That's how science as far as I understand it operates on competing theories the emphasis being on competing!

One or two people saying one thing is a hypothesis it's not science even if there's some research and some tests the back it up it has to be repeated elsewhere.
 

QMuse

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It's not a criticism of Toole and olive if anything is a criticism of competing theories. That's how science as far as I understand it operates on competing theories the emphasis being on competing!

One or two people saying one thing is a hypothesis it's not science even if there's some research and some tests the back it up it has to repeat it adamton item elsewhere.

Ok, stop bashing T&O, we have @tuga to do that and he's quite good at it. :D
 

Thomas savage

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Ok, stop bashing T&O, we have @tuga to do that and he's quite good at it. :D
I'm not bashing toole and olive, they are but two men.

I can find you two men in science that can show you about anything and make it look convincing

so if you're going to rely on it and you're going to put science in your forum name it needs to be based on more than that .

This is how people see it and it is how it really is. Whether anyone wants to address this or have the capabilities to address it i.e. we have supporting research from independent sources is another matter.

It's in the lack of that supporting or corroborating research I'd would just like to ask we be a little less absolutist when it comes to the harman research conclusions..
 

Thomas savage

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This is why F1 was so good , you can have all the ideas you want , highly technical and pioneering and backed by luminaries but the car either goes faster or it doesn't and believe me giving a bit of time that makes fools of everyone .

What we have here is a one car race.
 

QMuse

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I'm not bashing toole and olive, they are but two men.

I can find you two men in science that can show you about anything and make it look convincing

so if you're going to rely on it and you're going to put science in your forum name it needs to be based on more than that .

This is how people see it and it is how it really is. Whether anyone wants to address this or have the capabilities to address it i.e. we have supporting research from independent sources is another matter.

in the lack of that I would just like to ask we be a little less absolutist when it comes to the harm and research.

While it is true that T&O research have a reputation almost like a Bible it is also true that without comprehensive research everyone can tell you that you need to stick to the "Book" unless you can prove otherwise. But there's not much comprehensive research done lately in the audio and the future doesn't look too bright either.
 

Thomas savage

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While it is true that T&O research have a reputation almost like a Bible it is also true that without comprehensive research everyone can tell you that you need to stick to the "Book" unless you can prove it. And there's not much comprehensive research done lately in the audio and the future doesn't look too bright either.
A unfortunate reality. Is actually no different to my job, there's guys in America doing massive complexes that would swear blind how I go about my job is the wrong way however I earn more money than they do.

But then you have the added complexity of my skill and I am unusually skillful in my job so what's good for me isn't good for everyone and what's good for them isn't good for me and what's good for me isn't good for them. Different work environments same job different needs different skills different cultures It's complicated.

And that's just something as simple as spreading shit on a wall.

Taken to extremes it's highly complicated taken to extremes I practice kung fu, I invented my own kind of kung fu and that's why I'm as productive as I am. ( You might laugh but I literally have invented a martial art in the way I go about my job)

But you can take the disparities in personnel environment and apply them to listening environments thats not a one fits all solution.

Can you really say a £20,000 Harman speaker is a good idea if you're a dsp expert and have no or little domestic restraints in terms of subwoofer placement etc.

you make a niece ( or niche) small enough you'll find expertise the problem with that expertise that doesn't travel and it doesn't always make sense. if you have quite a intelligent mind and understand the expertise will you understand how it might apply to different environments but that is very rare.

it's the height of lunacy , people might come here and dismiss a speaker on a preference rating, trust me that's what they will do they take the number add it to the sub number and the higher it is the better it is.

that's not encouraging people to think and it's not encouraging people to understand expertise understand prejudicial environments ie rooms listening environments .

you have to take information in context and if you present absolute information in terms of preference rating and SINAD you have to be extremely careful about how you educate people on what those discerning values mean and how they apply to their situation.


You can think this is all bullocks but you need to understand there is a conversation to be had there's a debate and we need to host activate debate and you all need to be able to read and accept differing points of view. We are not in a religious cult we should not be offended by points of view we disagree with this is madness.

I don't often comment on these matters I just police read cope and manipulate discussion. Please at least give a thought and ask a question. It's not the worst place to be one could argue it's a privilege.
 
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JohnPM

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Maybe IMD works only when signal is played by generator and not with file. @JohnPM , is that so?
Almost. If you need to play the signal from a file generated by REW open the generator and select the same signal so REW knows what to calculate. The generator doesn't need to be running, just showing.
 

QMuse

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Almost. If you need to play the signal from a file generated by REW open the generator and select the same signal so REW knows what to calculate. The generator doesn't need to be running, just showing.

That's a neat trick, thank you!

What distance and what SPL would you recommend when measuring IMD in a room?
 

JohnPM

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What distance and what SPL would you recommend when measuring IMD in a room?
Close to the speaker, e.g. 1 metre, preferably with the speaker in the middle of the room. Level depends on what playback level you want to see the figures for, since distortion will increase with level.
 
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