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post #13501 of 15542 Old 08-27-2018, 04:46 PM
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Oh man!
The good Dr. did not disappoint
I'm guessing he has those poseable mannequin hand cable lifters
Sh-h-h-h! It's our secret . . . right? Wickedly posed, of course!
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post #13502 of 15542 Old 08-27-2018, 04:57 PM
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If the crossover really wasted 99% of the energy sent into it all of our speakers would need cooling towers on the back...

Engineering is not all that mysterious though takes some effort to learn (and much more to master), and crossovers, while complex and tricky because the end game is acoustic output from an electromechanical system and not just a basic electrical circuit, are relatively simple filter circuits compared to many filters used in audio and RF. Like much of engineering, art and imagination (if not innovation) is needed to produce a optimal result.

As for "poseable mannequin hand cable lifters", and "wickedly posed" at that, well, no comment in an open forum. It does increase my desire to visit Dr. Toole's listening room at some point.

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post #13503 of 15542 Old 08-27-2018, 05:30 PM
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Originally Posted by Floyd Toole View Post
Right. Although most designers aim for a flattish on-axis performance, it is not guaranteed. So, as far as on- and off-axis performances are concerned, there is no certain correlation. Listening or measuring at a distance within the near field is not a reliable indicator of anything.

Polar maps/response which showcase directivity (mentioned by Earl Geddes HERE will be useful info - IMHO speaker manufacturers ought to provide them.

$0.02

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post #13504 of 15542 Old 08-27-2018, 05:39 PM
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As for "poseable mannequin hand cable lifters", and "wickedly posed" at that, well, no comment in an open forum. It does increase my desire to visit Dr. Toole's listening room at some point.
Why, Don? Does the Dr. have poseable maple or myrtlewood cable lifters with 4 inch human fingernails?

After I read that article I thought of several things.
I think the 1st one was that Herb shouldn't overdo "The Herb" when writing copy.
I was waiting for him to work in Swirling Vortex somewhere and why doesn't he own full range driver speakers like Fostex or Bose 901s, etc.
His previous article for Audiostream was pretty much in the same vein as this one.

Look, I'm not into publicly bashing audio writers and I've seen videos with Mr. Reichert that are interesting & entertaining.
He has far more experience with tons of gear than I can even dream about.
I like certain writers a lot more when they review music.

 
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post #13505 of 15542 Old 08-27-2018, 05:49 PM
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Originally Posted by Kishore View Post
Polar maps/response which showcase directivity (mentioned by Earl Geddes HERE will be useful info - IMHO speaker manufacturers ought to provide them.

$0.02

Regards,
Kishore
No argument that measurements matter, and more measurements matter more. I am guessing you haven't read my book. It is all there. Polar plots are useful, but collections of off-axis measurements are arguably more informative.
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post #13506 of 15542 Old 08-27-2018, 06:55 PM
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a key question that alys confuses me is tests of speakers in mono 1 at a time vs the stereo sound...when I run rew on my speakers I see why mono might be ok as every individual speaker measures different...but when I run rew in stereo the results are totally different. I heard Dr Toole used mono for tests cause its easiest for science exam. but nobody listens in mono that I know...and stereo mesurements so different....anyways sure its in the book.

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post #13507 of 15542 Old 08-27-2018, 08:03 PM
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a key question that alys confuses me is tests of speakers in mono 1 at a time vs the stereo sound...when I run rew on my speakers I see why mono might be ok as every individual speaker measures different...but when I run rew in stereo the results are totally different. I heard Dr Toole used mono for tests cause its easiest for science exam. but nobody listens in mono that I know...and stereo mesurements so different....anyways sure its in the book.
Torii, you gotta read my book. It explains that we use mono tests because listeners were more sensitive to loudspeaker flaws than they were in stereo, not because it is easier. When we did - and we really did - compare stereo vs. mono results the winners were the same. There is no magic to listening in stereo, except that it is more entertaining - not more revealing of loudspeaker problems. When extended to multichannel listening, we are even less fussy. As far as "stereo soundstage and imaging" are concerned the dominant factor is the recording itself. There is more to it, and it is all discussed at length in the book.

As I have said countless times, room curves are not definitive measures of sound quality. Sorry to be so repetitive . . .
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post #13508 of 15542 Old 08-27-2018, 08:13 PM
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I kinda got it. and I will probably get your book for my bday soon. the problem always falls back to when I audition speakers I let my brain/ears take over. I try to think about height and sound of a specific instrument and even envision vocals dancing front and wide on the stage...etc...


only reason I post here is because Im thinking about buying the speakers...and the neutral argument just doesnt sell me. a few people on this thread peak my interest quite abit...and when I upgrade to 10-15k for towers I just need to ensure I dont want to keep on upgrading as if you cant design a speaker in that price range to sound awesome...its just fools gold.
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post #13509 of 15542 Old 08-27-2018, 08:14 PM
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Originally Posted by Floyd Toole View Post
...you gotta read my book. It explains...
My copy is arriving tomorrow. I look forward to being more educated in my future posts.
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post #13510 of 15542 Old 08-27-2018, 08:16 PM
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I have my UMIK-1 out and I'm heading downstairs to measure what's going on in my room. 99% of what these speakers are doing sounds amazing--but something's not right. I suspect a null in the 40-60hz range due to my room...

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post #13511 of 15542 Old 08-27-2018, 08:28 PM
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My copy is arriving tomorrow. I look forward to being more educated in my future posts.
Once you have the book you can follow along with Dr. Toole's posts a bit better. You can't reference the figures he points to without it!
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post #13512 of 15542 Old 08-27-2018, 08:54 PM
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At the time, in the 1970s, the Yamaha NS1000M was a significant technical achievement, albeit flawed. The designer of it, and the more famous (infamous?) NS10M visited me at the NRCC and we had a fruitful exchange. Some anechoic measurements of the NS1000 are shown in Figure 18.3(e) in my book. The engineering was superb, but the target performance was wrong - a flat sound power. This was influenced by the east coast (AR) philosophy of the time, as was the driver configuration (a large woofer extending to about 1 kHz before transitioning to a much smaller midrange). As a result there was some midrange coloration and aiming for flat sound power inevitably created a tendency to sound too bright (which many erroneously attributed to the metal diaphragms). A bit of tone control tilting made a big difference. It had very low distortion which the designer modestly attributed to "good engineering" in the motors.

That said, the NS1000M was a good performer at the time, something which cannot be said of its smaller brother the NS10M. As shown in Figures 12.10 and 12.11 the choice of a flat sound power target, which they achieved, meant that the on-axis performance was dreadful.
Dear Dr. Toole, although one wouldn't need a double blind test to tell that those Yammy NS1000s are indeed bright sounding (again, just how much is largely dependent on the kind of amplification used), the big 11.8in paper woofer crosses over to the beryllium midrange dome @ 500Hz (not 1kHz), which in turn extends its operation range up to 6kHz, allowing a very soft transition to the beryllium tweeter. Thus, being it a dome and a dome of such rigidity and lightness, one should have expected a very good/even sound dispersion characteristics and, hence, a very good off-axis frequency response in that range from a relatively small (only 3.5in) midrange dome.

What exactly made the NS1000 not as flawed as the NS10M (?), since they both had the same target performance - a flat sound power, as you say. Beryllium anyone?!

I'm sure that if Kevin Voecks and Mark Glazer had that beryllium midrange dome at their disposal, theirs and their team's enginnering effort would be greatly reduced. I guess one had to be an awful engineer to mess up a speaker design having such good drivers.


BTW, now that I'm on this, I must say I have the answer to a better Salon design, being it a cost no object loudspeaker... The Salon3 should have carbonfiber drivers instead of metal ones!!! In fact, I don't understand why isn't such a readily available material nowadays used for loudspeaker drivers manufacturing. Carbonfiber is getting increasingly cheaper, even my sports salo(o)n have it all over the place! Very stiff, very light and easily modulated intrinsic damping characteristics. No metal, can touch it, not even beryllium!

Harman must now pay me for such brilliant idea!

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post #13513 of 15542 Old 08-27-2018, 09:05 PM
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Dear Dr. Toole, although one wouldn't need a double blind test to tell that those Yammy NS1000s are indeed bright sounding (again, just how much is largely dependent on the kind of amplification used), the big 11.8in paper woofer crosses over to the beryllium midrange dome @ 500Hz (not 1kHz), which in turn extends its operation range up to 6kHz, allowing a very soft transition to the beryllium tweeter. Thus, being it a dome and a dome of such rigidity and lightness, one should have expected a very good/even sound dispersion characteristics and, hence, a very good off-axis frequency response in that range for a relatively small (only 3.5in) midrange dome.

What exactly made the NS1000 not as flawed as the NS10M (?), since they both had the same target performance - a flat sound power, as you say. Beryllium anyone?!

I'm sure that if Kevin Voecks and Mark Glazer had that beryllium midrange dome at their disposal, theirs and their team's enginnering effort would be greatly reduced. I guess one had to be an awful engineer to mess up a speaker design having such good drivers.


BTW, now that I'm on this, I must say I have the answer to a better Salon design, being it a cost no object loudspeaker... The Salon3 should have carbonfiber drivers instead of metal ones!!! In fact, I don't understand why isn't such a readily available material nowadays, used for loudspeaker drivers manufacturing. Carbonfiber is getting increasingly cheaper, even my sports salo(o)n have it all over the place! Very stiff, very light and easily modulated intrinsic damping characteristics. No metal, can touch it, not even beryllium!

Harman must now pay me for such brilliant idea!
Google it, sounds like some have tried it and there are problems with it
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post #13514 of 15542 Old 08-27-2018, 09:18 PM
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Oh no no no....I hate you terrible room.

I was correct in what I was hearing. Lots of resonance in the ultra low frequencies followed by a steep drop at 40hz, another around 65, and another just above 80.

I tried the low frequency adjustment on the Salon 2; but, that seems to affect all frequencies below 200hz fairly evenly so it doesn't resolve anything here.

Definitely interested in thoughts. I've tried adjusting the seating position and speaker placement in increments; but, my room doesn't have a ton of flexibility. I will say that moving the speaker forward about a foot or backward foot led to no real change. In fact, it was a bit worse.

I'm thinking that if I can tame the resonance below 40hz, it might help bring everything else in line.
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post #13515 of 15542 Old 08-27-2018, 09:20 PM
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Google it, sounds like some have tried it and there are problems with it

They have to learn with the auto industry then! I will check it...
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post #13516 of 15542 Old 08-27-2018, 09:40 PM
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Scan Speak already uses carbonfiber in some of their drivers.



Quote:
The high-compliance, low-compression drivers, custom-built to Sonus Faber's specs by Scan-Speak, consist of two extra-rigid, lightweight, 8" paper/carbon-fiber cone woofers, with the cone material "hand-thrown" to randomize the fibers (and break up resonances) and individually damped; a high-compliance, 7" multiple-coated paper/carbon-fiber midrange cone with a hyperbolic titanium phase plug (to break up high-frequency beaming); and a 28mm, non-ferrofluid, multiple coated soft-dome tweeter protected by a grate
But, I'm talking about something without paper, only pure carbonfiber!
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post #13517 of 15542 Old 08-28-2018, 05:35 AM
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This is the kind of "pure" carbonfiber I'm talking about which is now widely used in the automotive industry (aka CFRP):


Quote:
When impregnated with a plastic resin and baked it forms carbon-fiber-reinforced polymer (often referred to as carbon fiber) which has a very high strength-to-weight ratio, and is extremely rigid although somewhat brittle.
And, an old vid of its manufacturing process by BMW:






More recently,


BMW claims it's developed a process for fast, cheap carbon composite chassis manufacture


DISCLAIMER: My current sports saloon is not a BMW, nor I work or have ever worked for BMW.

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post #13518 of 15542 Old 08-28-2018, 06:26 AM
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Oh no no no....I hate you terrible room.

I was correct in what I was hearing. Lots of resonance in the ultra low frequencies followed by a steep drop at 40hz, another around 65, and another just above 80.

I tried the low frequency adjustment on the Salon 2; but, that seems to affect all frequencies below 200hz fairly evenly so it doesn't resolve anything here.

Definitely interested in thoughts. I've tried adjusting the seating position and speaker placement in increments; but, my room doesn't have a ton of flexibility. I will say that moving the speaker forward about a foot or backward foot led to no real change. In fact, it was a bit worse.

I'm thinking that if I can tame the resonance below 40hz, it might help bring everything else in line.
What kind of room correction do you have at your disposal? I don't like correcting above the schroeder frequency but if you have one that lets you limit the range you could try it. I personally use parametric EQ and only use filters up to 200Hz.
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post #13519 of 15542 Old 08-28-2018, 06:45 AM
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Might need some room treatment too, kill the corners.

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post #13520 of 15542 Old 08-28-2018, 07:30 AM
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What kind of room correction do you have at your disposal? I don't like correcting above the schroeder frequency but if you have one that lets you limit the range you could try it. I personally use parametric EQ and only use filters up to 200Hz.
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Might need some room treatment too, kill the corners.
I'm going to try more placement adjustments today. Then room treatment. Any form of EQ will be last. It's not that I'm anti-EQ; it's simply that EQ has some pretty strong limitations and I'm sure to be better off working on the physical space before manipulating frequency response.
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post #13521 of 15542 Old 08-28-2018, 09:17 AM
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One other thing to do before spending a lot of time trying to optimize the Salon2's full range, is high pass them @ 80Hz and see what your room look like. Use your subs below 80 and move them around.
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post #13522 of 15542 Old 08-28-2018, 09:17 AM
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I'm going to try more placement adjustments today. Then room treatment. Any form of EQ will be last. It's not that I'm anti-EQ; it's simply that EQ has some pretty strong limitations and I'm sure to be better off working on the physical space before manipulating frequency response.
What are the dimensions of your room? Is it open or closed? Do you have (a) subwoofer(s)?

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post #13523 of 15542 Old 08-28-2018, 10:05 AM
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Dear Dr. Toole, although one wouldn't need a double blind test to tell that those Yammy NS1000s are indeed bright sounding (again, just how much is largely dependent on the kind of amplification used), the big 11.8in paper woofer crosses over to the beryllium midrange dome @ 500Hz (not 1kHz), which in turn extends its operation range up to 6kHz, allowing a very soft transition to the beryllium tweeter. Thus, being it a dome and a dome of such rigidity and lightness, one should have expected a very good/even sound dispersion characteristics and, hence, a very good off-axis frequency response in that range from a relatively small (only 3.5in) midrange dome.

What exactly made the NS1000 not as flawed as the NS10M (?), since they both had the same target performance - a flat sound power, as you say. Beryllium anyone?!

I'm sure that if Kevin Voecks and Mark Glazer had that beryllium midrange dome at their disposal, theirs and their team's enginnering effort would be greatly reduced. I guess one had to be an awful engineer to mess up a speaker design having such good drivers.


BTW, now that I'm on this, I must say I have the answer to a better Salon design, being it a cost no object loudspeaker... The Salon3 should have carbonfiber drivers instead of metal ones!!! In fact, I don't understand why isn't such a readily available material nowadays used for loudspeaker drivers manufacturing. Carbonfiber is getting increasingly cheaper, even my sports salo(o)n have it all over the place! Very stiff, very light and easily modulated intrinsic damping characteristics. No metal, can touch it, not even beryllium!

Harman must now pay me for such brilliant idea!
It seems that you don't have my book to refer to. If you could look at the anechoic curves in Figure 18.3(e) you can easily see that the large woofer is having a significant effect up to 1 kHz on axis and contributing to a sagging off axis performance between 500 Hz and 1 kHz. The network may be trying to shut the woofer off at 500 Hz, but acoustically it is still a dominant factor for most of the next octave. Their goal of flat power response required them to let that part of the axial frequency response be elevated - resulting in the midrange coloration.

The problem with the NS10M had nothing to do with a lack of beryllium and everything to do with the directivity of 7-8 inch two-way loudspeakers, as was clearly shown in Figure 12.10.

Beryllium pushes the diaphragm breakup modes high in frequency, allowing the operational frequency range to be expanded. Other materials can work perfectly satisfactorily over more limited frequency ranges. Its low mass helps efficiency, which is also good. However, the directivity is determined by dimensions, not materials.

As for other diaphragm materials, there are several that would be attractive if they could be manufactured with sufficient consistency - fiber reinforced matrix cones are not new, kevlar and carbon being two options, but there are others, some involving nano technology I have heard. With premium Revel speakers aiming for 1 dB production consistency, end of line testing and tweaking are necessary and costly. Consistency, cost and complexity (and safety) are major issues. Making car bodies is not as demanding as making cones and domes, and even there human oversight is often required in the laying up of the fibrous material.

Engineers at Harman created one of the better new ones, called the ceramic metal matrix diaphragm, CMMD. It is deep anodized aluminum, creating exterior layers with ceramic stiffness and an interior of aluminum for damping. Low mass, high stiffness, easy to manufacture, and inexpensive (compared to beryllium to be sure). Varying the depth of anodization permitted its wide use in affordable speakers, including in cars, while deeper anodization worked well in premium products (the Infinity Prelude MTS, for example, which had no mechanical resonances within its operational range). It remains an option for all products.

We await the widespread availability of 'Unobtanium" which we hear beats them all. Meanwhile, the choice of diaphragm materials involves tradeoffs. People get enthused about materials, when the real issues often relate to the design of the motors - efficiency, power compression, non-linear distortion, etc. - which are hidden virtues or problems. When the performance of loudspeakers has plateaued at a high level it is not uncommon to seek out different, exotic sounding materials just to be different. Differentiation becomes a marketing issue.

Fortunately, with adequate anechoic data it is possible to anticipate the sound quality from loudspeakers - whatever materials are used.
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post #13524 of 15542 Old 08-28-2018, 02:01 PM
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It seems that you don't have my book to refer to. If you could look at the anechoic curves in Figure 18.3(e) you can easily see that the large woofer is having a significant effect up to 1 kHz on axis and contributing to a sagging off axis performance between 500 Hz and 1 kHz. The network may be trying to shut the woofer off at 500 Hz, but acoustically it is still a dominant factor for most of the next octave. Their goal of flat power response required them to let that part of the axial frequency response be elevated - resulting in the midrange coloration.

The problem with the NS10M had nothing to do with a lack of beryllium and everything to do with the directivity of 7-8 inch two-way loudspeakers, as was clearly shown in Figure 12.10.

Beryllium pushes the diaphragm breakup modes high in frequency, allowing the operational frequency range to be expanded. Other materials can work perfectly satisfactorily over more limited frequency ranges. Its low mass helps efficiency, which is also good. However, the directivity is determined by dimensions, not materials.

As for other diaphragm materials, there are several that would be attractive if they could be manufactured with sufficient consistency - fiber reinforced matrix cones are not new, kevlar and carbon being two options, but there are others, some involving nano technology I have heard. With premium Revel speakers aiming for 1 dB production consistency, end of line testing and tweaking are necessary and costly. Consistency, cost and complexity (and safety) are major issues. Making car bodies is not as demanding as making cones and domes, and even there human oversight is often required in the laying up of the fibrous material.

Engineers at Harman created one of the better new ones, called the ceramic metal matrix diaphragm, CMMD. It is deep anodized aluminum, creating exterior layers with ceramic stiffness and an interior of aluminum for damping. Low mass, high stiffness, easy to manufacture, and inexpensive (compared to beryllium to be sure). Varying the depth of anodization permitted its wide use in affordable speakers, including in cars, while deeper anodization worked well in premium products (the Infinity Prelude MTS, for example, which had no mechanical resonances within its operational range). It remains an option for all products.

We await the widespread availability of 'Unobtanium" which we hear beats them all. Meanwhile, the choice of diaphragm materials involves tradeoffs. People get enthused about materials, when the real issues often relate to the design of the motors - efficiency, power compression, non-linear distortion, etc. - which are hidden virtues or problems. When the performance of loudspeakers has plateaued at a high level it is not uncommon to seek out different, exotic sounding materials just to be different. Differentiation becomes a marketing issue.

Fortunately, with adequate anechoic data it is possible to anticipate the sound quality from loudspeakers - whatever materials are used.
Dr. Toole, I have heard some say that beryllium is not as well suited for a midrange compared to ceramic due to the fact that it's not internally damped, would such low level resonances be audible or do you think it's inaudible as long as there are no FR peaks associated with such ringing?
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post #13525 of 15542 Old 08-28-2018, 02:33 PM
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But Dr. Toole the only thing memorable about the NS1000 was its Beryllium drivers. Why?

Not just because they were exotic stuff! As I've said, beryllium made possible to manufacture a midrange dome of 3.5in capable of operate from just below 500Hz to above 6kHz.

As you say, directivity is determined by dimensions and I'll also add shape. A dome is omnidirectional provided it doesn't start to exhibit breakup modes! That's what characterizes dome tweeters. Now try to produce a dome that is able to operate in such wide frequency range at 90dB (1m, 1 watt) with materials other than beryllium. ATC being able to produce a proper 75mm (3in.) soft dome mid-range driver is some sort of engineering miracle (but it doesn't go as high in the frequency range nor it has the same efficiency)! Midrange transperancy is greatly enhanced with such dome drivers and I bet beryllium has the edge (pun intended) over textile domes. Isn't that why Revel uses metal drivers after all?!

Two-way loudspeakers, by definition, don't benefit of such midrange dome, so for every two-way design there will always be that inherent limitation, which will always be their biggest enginneering challenge if one wants decent bass output.

I guess that paper simply wasn't good enough of a material for such big cone and made it even worse in the NS10M! Monitor Audio latest Silver 100s are a two-way design with a 8" woofer and an even higher crossover point (2.8kHz against 2.0kHz of the NS10M) and don't sound remotely as bad.

But I'm sure that a beryllium tweeter would have allowed to lower the crossover frequency in the NS10M (as it happens w/ Revel Performa Be models range) and therefore would have helped to mitigate the phenomenon.

Oddly enough, when using the NS10M "recording engineers sought to dull its treble response by hanging tissue paper in front of it, resulting in what became known as the "tissue paper effect".

As for the driver motors, stiffer, lighter driver materials allow the usage of bigger, more powerful motors for the the same (or less) driver net weight, which helps heat dissipation, meaning they run cooler and hence with less heat compression at high SPLs, while keeping efficiency by virtue of the reduced weight.

On the other hand, one can see in the NS1000M owner's manual how the elevated axial frequency response can be tamed with the level control set to -3dB.

Finally, the same way smartphones, laptops and the likes have paved the way for electric cars with the battery tecnhology becoming increasingly better and cheaper, I also believe that automotive industry will help carbon fiber to be readily available for many other applications at a competitive cost, such as loudspeakers drivers!


Revel Salon3 CF... sounds goooood!!!

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post #13526 of 15542 Old 08-28-2018, 03:02 PM
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Dr. Toole, I have heard some say that beryllium is not as well suited for a midrange compared to ceramic due to the fact that it's not internally damped, would such low level resonances be audible or do you think it's inaudible as long as there are no FR peaks associated with such ringing?
These days it is possible for transducer engineers to predict, using computer models, cone or dome behavior with impressive accuracy. The material is just the starting point. The thickness, the profile of the radiating surface, how the perimeter is terminated, etc. all factor into the performance. The general idea is not to have any resonances within the operating bandwidth of each transducer. Usually this is achieved by moving the first breakup mode well above the upper operating limit, leaving essentially pistonic behavior. If a resonance remains within the operating range, its audibility must be evaluated. All of this is visible in high resolution anechoic measurements - if there is a bump, and the bump persists through spatial averaging over large solid angles, it is a resonance. The next action is to determine, based on existing detection threshold data, whether the residual resonance is audible. These days achieving functionally resonance-free performance is possible.

For a given operational bandwidth several materials may be comparably satisfactory. They will differ in cost, consistency and mass (efficiency), but may all sound the same. Beryllium is attractive for tweeters because these days "ultra wide bandwidth" is a popular interest, and selling point, whether it is audible or not. It may or may not be uniquely advantageous in other applications - it depends on the design intent.

Damping is not necessarily a solution. Damping a high-Q narrow resonance turns it into a lower-Q wider resonance. Strangely enough, as measured in frequency response deviations, we are much more sensitive to low-Q (wider bandwidth) resonances than we are to high-Q ones - the ones that ring energetically. Why? Because they are narrow band they are less likely to be energized by music. A Q=50 resonance can show a 10 dB peak, a narrow spike in the frequency response, before it is audible in typical pop music. There is truth in the old expression "good enough for rock and roll" :-) In contrast, we can detect low-Q humps of much less than 1 dB with high spectral density sounds like pink noise. This is why specifications like +/- 3 dB are a joke. It is why loudspeakers that "measure the same" sound different. They probably are. Chapter 4 in my book discusses resonances, and Figure 4.10 shows this dramatically.

Incidentally, we don't hear the ringing. We detect the amplitude response bump. It is all discussed in peer reviewed AES papers and in my books.
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post #13527 of 15542 Old 08-28-2018, 04:11 PM
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How does the Magico get such good off axis integration with tweeter and 6” midrange in the S5? No waveguide. NRC data:


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Take note that with a dome midrange transducer with such characteristics due to beryllium, as found in the Yamaha NS1000, a lens to limit the dispresion characteristics of the tweeter dome and the waveguide to boost its output at the crossover frequency, in order to match those of the conventional mid/bass cone, would have been rendered useless! Simply because this time there is two domes, mid-range and tweeter, running with identical behaviour. Also, high-order crossovers could be replaced by simpler ones, with more gentle slopes, which means less electric parts and greater signal integrity.


Off-axis frequency response would be therefore greatly enhanced and the engineering effort to attain it, without all the added complexity, greatly reduced.


That's its beauty!

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NullTest said:

"Not just because they were exotic stuff! As I've said, beryllium made possible to manufacture a midrange dome of 3.5in capable of operate from just below 500Hz to above 6kHz." As the measurements show: they get a lot of help from the woofer up to about 1 kHz. It certainly is not bearing the full load above 500 Hz. I'm not belittling Be, just keeping the facts straight

"A dome is omnidirectional provided it doesn't start to exhibit breakup modes! That's what characterizes dome tweeters." A pulsating dome may be omnidirectional, but a rigid one cannot be. At wavelengths approaching and above the diameter they beam and, depending on the shape of the dome and the behavior of its surround, there may be interference effects. Again, don't trust me, look at the data.

"I guess that paper simply wasn't good enough of a material for such big cone and made it even worse in the NS10M! Monitor Audio latest Silver 100s are a two-way design with a 8" woofer and an even higher crossover point (2.8kHz against 2.0kHz of the NS10M) and don't sound remotely as bad." My guess is that the Monitor Audio was designed with a flattish on-axis response, not sound power. It would have to sound better. BTW, treated paper cones can be remarkably good - see the JBL Pro M2.

"Oddly enough, when using the NS10M "recording engineers sought to dull its treble response by hanging tissue paper in front of it, resulting in what became known as the "tissue paper effect". Yes that is so, but there is some confusion. The original NS10M exhibited a much elevated tweeter level relative to the woofer (Figure 12.10). It was designed as a consumer product to be placed against a wall (bass boost)and listened to at a distance (attenuated midrange boost). However, placed on the meter bridge of a recording console it was Bright! So, hang some tissue paper in front of the tweeter, just as any sensible person would do - don't for goodness sake go find a better speaker. The professional version had better woofer to tweeter level balance, but there was a huge hump in the upper midrange (Figure 12.11). Tissue wouldn't help, but I know some who still used it "because".

"On the other hand, one can see in the NS1000M owner's manual how the elevated axial frequency response can be tamed with the level control set to -3dB." Unfortunately it covers far too large a frequency range, and does as much harm as good. The problem is much narrower in bandwidth.

"Revel Salon3 CF... sounds goooood!!!" If well designed, one would hope so. A little more efficiency would be good and lighter cones help. Eliminating need to reproduce the lowest bass would also help - convince people to employ bass management and spend some money on powered closed box subwoofers (2 or 4) which can address room modes - those are resonances that speaker manufacturers cannot control. Chapter 8.
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post #13530 of 15542 Old 08-28-2018, 05:01 PM
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How does the Magico get such good off axis integration with tweeter and 6” midrange in the S5? No waveguide. NRC data:


At soundstage. Can’t post link yet.
Can't answer your question. However, i have listened to the Magico's and thought they were as good as speakers that list for at least 10% the cost of Magico.
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