I'm curious what in your reply to me you consider actually responsive to the question I posed, which was limited to your directivity claim. The answer would be a polar map showing the pattern you claim.
As I wrote, I've played with BMR's and found them to offer no more constant pattern control than similar-diameter cone drivers. That is to say, the typical omni at the bottom and narrowing with some peakiness as you go up in frequency. Perhaps yours is different, but you haven't provided any reason to believe that is the case.
Also, if your standard for comparison is the Manger driver, we have different standards. I've heard that driver in one of their own systems and in a DIY system, and the it does not impress me at all. Beamy as all get out up top, and no dynamic capability whatsoever even in their three-driver setup.
That is not really true. In the modal region it makes no difference if the source in in the wall, at the wall or in the room, the general character of the modal issues will be the same. I cannot see how "no further EQ is required."
So you don't accept the equivalency of the time and frequency domains? That's pretty fundamental.
I find that only audiophiles/novices use waterfalls. Toole nor anyone else that I know in the professional world use them because we all understand that there is nothing in the time domain that is not also in the frequency domain. They are just two different ways of looking at the same things. The frequency domain tends to show a more data at one time than the time domain. It would take many pages of waterfalls to show equivalent data to a polar map.
Is BMR Bending Mode Radiator or something else? Its directivity at lower frequencies has to be the same as any equivalent sized source because the wavelengths are so long. They don't know bending from pistonic. At very high frequencies the BMR will tend to beam less, but in a rather erratic fashion. Not "controlled" at all.
Until we have that then its all just here say then isn't it?
I am always willing to analyze data for my PolarMap program. It is not hard to take the data, I do it all in my living room. Takes about 15 minutes once you are setup. You do not need an anechoic chamber. It's better to take the right data in a poor room than the wrong data is an great room. You can take the data for as little as $US100 (Mic and preamp and wood for a turntable.)
I think that I will post a white paper on building this system as it is quite trivial to assemble. Then maybe we can all be looking at real data and not just guessing at how "good" our speakers are.
Of course, I don't do waterfalls. But once you have the raw data then you can still do all that "other" stuff if you want. When you see what real speakers work like in a full polar diagram you will understand how hard it is to get it right and why so few speakers do.
That will be great. Someday hopefully there would be then a large collection of polar map data for various DIY and commercial designs..
I would love to see that paper Dr.Geddes, it should even the playing field so people like me with limited scientific background can start creating meaningful measurements and discussing them here in common terms.
Above and beyond as always mate.. I hope you find the time and energy! Thanks in advance.
Dean
Above and beyond as always mate.. I hope you find the time and energy! Thanks in advance.
Dean
Polar measurements of on wall array's
Hi Pallas and Earl,
There are several very good reasons I cant publish measurements until Christmas.
(1) The prototype speakers I have been using for development and demo's are all based on different versions of the BMR which I have been developing since 2010...I have only just signed off on the OEM order for the production drivers (both the rubber and the silk surround versions) which are due to arrive in early December (subject to pre Christmas shipping from China!).
(2) I want to be able to show the flexibility of the driver ie not just as a full line array on wall, but also used I as mini arrays on wall or even in singles as a near-field monitor or stand-mount. This is a lot of speakers and a heck of a lot of drivers and a huge amount of work to get it all right.
I only have 4 pre production BMR's with the silk surround ...
(2) I cant use the traditional speaker in the middle of a large room on a wooden turntable with a static mic on a tripod...The majority of my designs are for on or in wall....I need a large clear wall where the speaker remains static and its the Mic which moves around....This as I am sure you are aware is not so simple as it sounds!
(3) Many years ago when I was developing this 6moons audio reviews: Overkill Audio Encore Speaker System
I made the mistake of publishing some of my home measurements....Oh boy, never again! This time round I will wait until I have a full suite of independent professional measurements which are not open question ie Derek cooked the results!
(4) I will also be holding back from publishing the measurements until I have finished the demo's to enable me to publish independent reviews of the speakers to accompany the measurements....
Reviews by Pro sound guys who mix and master for a living and professional musicians who obviously know what they are talking about....These are vital....The reviews may not interest you guys but they are critical to establishing credibility in the commercial world....Again Floyd mentions this very point in Pallas's video link a few posts back...
Time flies nowadays so hope to be able to come back with the high quality data you guys quite rightly have asked for...So until then you can level me with " Yup heard it all before...All talk and no data...!" and I have no answer...Unless you want to pop over for a demo!!!
Cheers
Derek.
PS Pallas, if you heard the Manger with a passive crossover...You have not heard the Manger. I met Daniela and Prof Manger on several occasions and the bottom line is, after they heard my DSP / active Manger speaker they agreed it was a night and day difference...But in the commercial world the market for $80,000 floor standing monster speakers started to decline 20 years ago and by 2010 was almost dead...Today the $$$monster flagships are just for PR and marketing....Even the billionaires who can afford them are bored with them.
Hi Pallas and Earl,
There are several very good reasons I cant publish measurements until Christmas.
(1) The prototype speakers I have been using for development and demo's are all based on different versions of the BMR which I have been developing since 2010...I have only just signed off on the OEM order for the production drivers (both the rubber and the silk surround versions) which are due to arrive in early December (subject to pre Christmas shipping from China!).
(2) I want to be able to show the flexibility of the driver ie not just as a full line array on wall, but also used I as mini arrays on wall or even in singles as a near-field monitor or stand-mount. This is a lot of speakers and a heck of a lot of drivers and a huge amount of work to get it all right.
I only have 4 pre production BMR's with the silk surround ...
(2) I cant use the traditional speaker in the middle of a large room on a wooden turntable with a static mic on a tripod...The majority of my designs are for on or in wall....I need a large clear wall where the speaker remains static and its the Mic which moves around....This as I am sure you are aware is not so simple as it sounds!
(3) Many years ago when I was developing this 6moons audio reviews: Overkill Audio Encore Speaker System
I made the mistake of publishing some of my home measurements....Oh boy, never again! This time round I will wait until I have a full suite of independent professional measurements which are not open question ie Derek cooked the results!
(4) I will also be holding back from publishing the measurements until I have finished the demo's to enable me to publish independent reviews of the speakers to accompany the measurements....
Reviews by Pro sound guys who mix and master for a living and professional musicians who obviously know what they are talking about....These are vital....The reviews may not interest you guys but they are critical to establishing credibility in the commercial world....Again Floyd mentions this very point in Pallas's video link a few posts back...
Time flies nowadays so hope to be able to come back with the high quality data you guys quite rightly have asked for...So until then you can level me with " Yup heard it all before...All talk and no data...!" and I have no answer...Unless you want to pop over for a demo!!!
Cheers
Derek.
PS Pallas, if you heard the Manger with a passive crossover...You have not heard the Manger. I met Daniela and Prof Manger on several occasions and the bottom line is, after they heard my DSP / active Manger speaker they agreed it was a night and day difference...But in the commercial world the market for $80,000 floor standing monster speakers started to decline 20 years ago and by 2010 was almost dead...Today the $$$monster flagships are just for PR and marketing....Even the billionaires who can afford them are bored with them.
Then "after Christmas" is a good time to make claims about pattern control. Before actually having the measurements, not so much.
Sure you can, to verify polar response in the mids and treble.
The crossover cannot improve the extremely narrow treble dispersion nor the meager output limits of the drive unit.
For the avoidance of doubt...
Hi Pallas,
Re your 3 points:
To be accurate and avoid any confusion with common terms from your world of loudspeaker design:
(1) I am not making any claims about "pattern control".... I avoid all pattern control at all costs!
I believe pattern control it is a limiting factor not a design feature!
I am making claims about the exact opposite....Zero "control" ie very broad and even dispersion in both vertical and horizontal planes without any wave guides, horns or flares.
(2) Further more designing the loudspeaker for on wall / in wall takes advantage of ( not fighting against) boundary reinforcement. I use the low midrange upper bass boost as part of the design....This is why I need to measure the speakers on a flat wall...Not out in a room.
Using my prototype drivers I have my own measurements which are reliable enough for me to spend £20K on OEM drivers....But I know that no matter what I publish it will be shot down in flames....So I will remove that option from the equation by hiring an independent professional who is beyond reproach.
There is lots of stuff on line about the other BMR designs that will give you a good indication of the off axis power response....Google Martin Colloms BMR tests reports, also CSS publish graphs of a few good BMR's. The Hi Wave stuff sounds pretty bad but measures well.
(3) Re the Manger....I used the Manger with a DEQX which enabled the use of linear phase brick wall (well 96 dB per octave slopes) at 300Hz to 400Hz to crossover the Manger to very dynamic bass mid driver ( the original Beyma LX12 60) and this transformed the dynamics and power handing of the Manger...It could keep up the Pro driver and hit peaks of 110dB....I blew a conventional passive crossver'd Manger at 98dB peaks with a "like for like" testing method....Expensive test but worthwhile!
A Manger working below 400 Hz is severely compromised in Dynamics. The right DSP and bass system fixes that problem.
Cheers
Derek.
Hi Pallas,
Re your 3 points:
To be accurate and avoid any confusion with common terms from your world of loudspeaker design:
(1) I am not making any claims about "pattern control".... I avoid all pattern control at all costs!
I believe pattern control it is a limiting factor not a design feature!
I am making claims about the exact opposite....Zero "control" ie very broad and even dispersion in both vertical and horizontal planes without any wave guides, horns or flares.
(2) Further more designing the loudspeaker for on wall / in wall takes advantage of ( not fighting against) boundary reinforcement. I use the low midrange upper bass boost as part of the design....This is why I need to measure the speakers on a flat wall...Not out in a room.
Using my prototype drivers I have my own measurements which are reliable enough for me to spend £20K on OEM drivers....But I know that no matter what I publish it will be shot down in flames....So I will remove that option from the equation by hiring an independent professional who is beyond reproach.
There is lots of stuff on line about the other BMR designs that will give you a good indication of the off axis power response....Google Martin Colloms BMR tests reports, also CSS publish graphs of a few good BMR's. The Hi Wave stuff sounds pretty bad but measures well.
(3) Re the Manger....I used the Manger with a DEQX which enabled the use of linear phase brick wall (well 96 dB per octave slopes) at 300Hz to 400Hz to crossover the Manger to very dynamic bass mid driver ( the original Beyma LX12 60) and this transformed the dynamics and power handing of the Manger...It could keep up the Pro driver and hit peaks of 110dB....I blew a conventional passive crossver'd Manger at 98dB peaks with a "like for like" testing method....Expensive test but worthwhile!
A Manger working below 400 Hz is severely compromised in Dynamics. The right DSP and bass system fixes that problem.
Cheers
Derek.
Derek
Your point #1 just doesn't make any sense. "i.e. very broad and even dispersion in both vertical and horizontal planes" IS pattern control. It's just a low Q pattern. You need to show that this has been achieved not just claim that it is so. I have never seen a BMR achieve such a result and the theory supports that.
Your point #2 is true up to the "upper bass", but above that flush mounting has no effect different than a box with rounded corners. So where the directivity actually matters, measuring free field is just as reliable as in a wall and not doing so just sounds like a cop-out.
To #3, I have seen data on Mangers, they don't measure very well at all. The subjective reviews are all over the place which just supports my belief that subjective reviews are kind of useless.
Your point #1 just doesn't make any sense. "i.e. very broad and even dispersion in both vertical and horizontal planes" IS pattern control. It's just a low Q pattern. You need to show that this has been achieved not just claim that it is so. I have never seen a BMR achieve such a result and the theory supports that.
Your point #2 is true up to the "upper bass", but above that flush mounting has no effect different than a box with rounded corners. So where the directivity actually matters, measuring free field is just as reliable as in a wall and not doing so just sounds like a cop-out.
To #3, I have seen data on Mangers, they don't measure very well at all. The subjective reviews are all over the place which just supports my belief that subjective reviews are kind of useless.
Not sure exactly what that means (though it just sounds like vacuous sales-blabber to me) but anyway....
Excuse me? Are these not your exact words:
[emph. added]
To any literate person, the bolded text above is a very specific pattern control claim, as is the blue text. The underlined text is more general, but nonetheless is also a pattern control claim.
Last time I checked, 3 > "any."
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Ouch - don't mess with a lawyer AND a physics PhD. You are just asking for trouble.
Derek - I get the impression that you are pretty young (compared to me everyone here is probably pretty young.) You have a tendency to make claims without much support. Age tends to correct that all-too-typical problem. My 15 Yr. old son claims all kinds of outrageous things with nothing but a passing idea as to support - "I think this therefor it must be true". It never even enters his mind that someone might question his claims. Pallas is a lawyer and they are trained from the get-go to demand support for everything - what would a trial be without evidence? (Trouble is that jurists don't understand what evidence is - been there!)
Derek - I get the impression that you are pretty young (compared to me everyone here is probably pretty young.) You have a tendency to make claims without much support. Age tends to correct that all-too-typical problem. My 15 Yr. old son claims all kinds of outrageous things with nothing but a passing idea as to support - "I think this therefor it must be true". It never even enters his mind that someone might question his claims. Pallas is a lawyer and they are trained from the get-go to demand support for everything - what would a trial be without evidence? (Trouble is that jurists don't understand what evidence is - been there!)
Snow on the roof....But fire in the grate!!
Yup, that's me...Handsome devil eh?!!
Yup, that's me...Handsome devil eh?!!
Premature publication..Its never happened before!
Thanks Earl,
I like to think I am still young at heart....But my body ain't believing it!
One of my biggest failings is lack of patience, I hold my hands up...Guilty as charged...I do hope to make it up to you all with a nice Christmas present
Mixing it with Pallas or any one else is good practice for the real world outside the geeky forums....I do learn a lot but just don't admit here...Ooops did I just say that out loud?
No one means any harm really its just we are all passionate about music and want to use our best efforts to further our own beliefs...
Also to build a business out of our passion is great motivation...Most of the guys on the forum would secretly love to be able to commercialise an audio idea and earn a living from it.... Most of us fail but the few talented and lucky enough to succeed keep the dream alive for everyone...
I say good luck to us all and may the best sounding systems rise above the crowd to fame and fortune...Hope one of them is mine!
All the best
Derek.
Ouch - don't mess with a lawyer AND a physics PhD. You are just asking for trouble.
Derek - I get the impression that you are pretty young (compared to me everyone here is probably pretty young.) You have a tendency to make claims without much support. Age tends to correct that all-too-typical problem. My 15 Yr. old son claims all kinds of outrageous things with nothing but a passing idea as to support - "I think this therefor it must be true". It never even enters his mind that someone might question his claims. Pallas is a lawyer and they are trained from the get-go to demand support for everything - what would a trial be without evidence? (Trouble is that jurists don't understand what evidence is - been there!)
Thanks Earl,
I like to think I am still young at heart....But my body ain't believing it!
One of my biggest failings is lack of patience, I hold my hands up...Guilty as charged...I do hope to make it up to you all with a nice Christmas present
Mixing it with Pallas or any one else is good practice for the real world outside the geeky forums....I do learn a lot but just don't admit here...Ooops did I just say that out loud?
No one means any harm really its just we are all passionate about music and want to use our best efforts to further our own beliefs...
Also to build a business out of our passion is great motivation...Most of the guys on the forum would secretly love to be able to commercialise an audio idea and earn a living from it.... Most of us fail but the few talented and lucky enough to succeed keep the dream alive for everyone...
I say good luck to us all and may the best sounding systems rise above the crowd to fame and fortune...Hope one of them is mine!
All the best
Derek.
Just wanted to add my 5c of experience:
Everyone is good at measuring frequency response calling "that's it" when flat, but few pay attention to speed attack, macro and micro dynamics because they are hard to measure and specify in digits.
The best midrange in multi way i got was so far from 8" inch very light cone driver with very strong motor (Troels Gravesen JA8008). I'll be taking this driver with me to active multi-way system even though my choice of drivers is virtually unlimited in this case...Although not very universal or suitable for anything but extended midrange - none of expensive drivers i had could match it's dynamics and attack influencing my choice of drivers from that moment.
Yes and by a lot. Maybe less so than in bass region where i found large, low MMS, high BL drivers to sound superior to any heavy cone drivers with weak motor (unless with servo), but all the same applies to midrange, especially lower region.
Everyone is good at measuring frequency response calling "that's it" when flat, but few pay attention to speed attack, macro and micro dynamics because they are hard to measure and specify in digits.
A 6.5 heavy cone can sound lazy easily. But It totaly depends on cone mass/motor strength/travel distance (displacement).
The best midrange in multi way i got was so far from 8" inch very light cone driver with very strong motor (Troels Gravesen JA8008). I'll be taking this driver with me to active multi-way system even though my choice of drivers is virtually unlimited in this case...Although not very universal or suitable for anything but extended midrange - none of expensive drivers i had could match it's dynamics and attack influencing my choice of drivers from that moment.
Totally agree!
Well said Alexander,
I have had very similar results from experimenting with lots of drivers.
I have spent literally 100's of hours posting and arguing that a low Mms to Bl ratio is the most vital parameter to get right in any cone or dome driver, esp in the 100Hz to 5KHz band.
There are a lot of guys who say the only thing counts is driver inductance and if you lower that with lots of copper you can make a heavy cone with weak motor perform the same as a low mass cone with High Bl....I believe that's utter rubbish!
All the best
Derek.
PS
If you are interested in this subject please search my old posts .....There are lots of details going back about 8 years on this subject.
Some great options for medium and large format drivers that meet this criteria are:
Well said Alexander,
I have had very similar results from experimenting with lots of drivers.
I have spent literally 100's of hours posting and arguing that a low Mms to Bl ratio is the most vital parameter to get right in any cone or dome driver, esp in the 100Hz to 5KHz band.
There are a lot of guys who say the only thing counts is driver inductance and if you lower that with lots of copper you can make a heavy cone with weak motor perform the same as a low mass cone with High Bl....I believe that's utter rubbish!
All the best
Derek.
PS
If you are interested in this subject please search my old posts .....There are lots of details going back about 8 years on this subject.
Some great options for medium and large format drivers that meet this criteria are:
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