great clip and good summary of the loudspeakers qualities! I enjoy the BeoLab 90s every day! Only downside: you have to live with some audiophile envy… ;-) Nothing comes close to sound quality and its amazing design! Thanks again, Pascal :-)
Gary Eickmeier says:
Geoff please have your engineers write to me. Please. None of your radiation patterns are correct for the goals that you – that we all seek.
Briefly – if you have heard about the DBX Soundfield One and how it was developed, that is the frontal radiation pattern that you need for good imaging all across the room. The technique is called distance/ intensity trading and it determines the lateral localization part of imaging. Do that with the front drivers.
The part of the radiation pattern that determines depth and spaciousness is the rear half. It needs to be cast to the rear at 30 to 45 degrees to each side to get the delayed lateral reflections moving and to maintain the central imaging in the depth dimension. Furthermore, it needs to be stronger than the frontal radiation to cause a harmless image shift to the rear, to get the imaging outside the actual speakers and make them disappear as obvious sources of the sound. That is what causes transparency of imaging.
You then have a much simpler design that achieves ALL of your objectives that you are trying to handle with hundreds of complications and it does it with one design. The technique, or theory, works best with specular reflectivity from the walls near the speakers, but high end customers would be willing to remodel their audio rooms however necessary to get the most out of the design and it would work quite well in most other rooms as well. The speakers must be positioned 1/4 of the room width in from the side walls and an equal amount out from the front wall to achieve perfectly even imaging all across the front of the room.
Gary Eickmeier
Lakeland, Florida
Mr10percent says:
Gary,
Seems to me you got some great ideas for a world-class loudspeaker system. Why don’t you design, build and market your concept yourself?
I don’t think Bang & Olufsen will be interested in your ideas to be honest. I don’t think they will change their thinking on the BL90 after 12years of development. You are as they say a little late to this party. Maybe Wilson, B&W or Sonus et al may be more interested?
Thanks for your continued enthusiasm in following the information on my website.
As I said before, I think that we have to agree to disagree. The loudspeaker directivity recommendations that you’ve outlined repeatedly in your comments here are in direct contradistinction with the intention and philosophy behind BeoLab 90’s “Narrow” mode. However, as I described in a previous reply, if you prefer to have a higher level of reflected sound from a loudspeaker, this can be currently achieved either by using BeoLab 90’s “Omni” or “Wide” modes – or by using the Beam Rotation feature to direct the main axis of the radiation away from the listening position as a method of adjusting the direct-to-“reverberant” level ratio to suit your preference (I use the word in quotation marks, since a small room can not be said to be truly reverberant).
As I also mentioned before, I suggest that you have a listen to BeoLab 90. I fully expect that the “Narrow” mode will not be to your taste, however, it might be that the other modes are more similar to your preferences.
I would also like to request that we bring this debate/discussion to a close. It seems to me that we opposing viewpoints not only regarding the desirable directivity pattern of a loudspeaker, but methods of its implementation, and I doubt that either of us will convince the other to change his mind.
Great to hear that you’re still happy with your loudspeakers. Thanks very much for the comment! :-)
cheers
– geoff
Gary Eickmeier says:
Geoff – I will let it go if you don’t want to communicate with me in private Email, but I have just one last question. How much of your 12 year project was devoted to the question of what radiation pattern should we want?
To answer your last question: Of course there is no way to tell how many hours of the BeoLab 90 development process were devoted to the design of the various directivity patterns. However, I would estimate that roughly 2 years of the 8-year development process were spent specifically on this. However, that’s just the time spent on the BeoLab 90… The general design of loudspeaker directivity and its implications at the listening positions, not only spatially, but also temporally and timbrally, have been perennial topics of discussion at Bang & Olufsen going back to the 1950’s. A short history of this was exactly the topic of an article that I co-wrote for this book.
The one issue that is not touched on in there, but is also worth noting (and has been discussed at B&O as well as at least one other manufacturer, based on historical AES publications) is the relationship and implications of loudspeaker directivity and noise/distortion. To give just one simple example of this: if you have a loudspeaker driver that behaves pistonically for its linear components, but exhibits “breakup” in higher frequency bands, you can have a situation where the non-linear products are much louder than the linear output in that frequency region when measured off-axis. In other words, the frequency-dependent directivity of a loudspeaker driver’s (unwanted) distortion artefacts is not necessarily the same as it is for its desired output – and this has a potentially worrisome effect on its off-axis response (and therefore the reflected response). Of course, this is further complicated by diffraction caused by the surrounding baffle. But, as I said, this is just one example…
I still owe you the bibliography listing the papers from the Archimedes project – I haven’t forgotten – but this week has been a little busy… sorry I’m late with delivering on that.
Cheers
-geoff
Gary Eickmeier says:
Geoff –
You don’t “owe” me anything but I would appreciate some of the biggest findings of the Archimedes project. Also, when you say you wrote the pertinent article on loudspeaker directivity in the “100 Years” book, which pages would that be? I would download and print them out if I knew.
Gary
David Moran says:
GM, I owe you are report of the BAS BL90 meeting and audition at the local dealer, plus informal measurements. V nice even with a most suboptimal room. But I have misplaced our email re concert A error, so can you kindly resend me your contact info privately? tnx, –David
Gary Eickmeier says:
Geoff, I have now heard the BL90 at your Gulfstream dealer down near Ft Lauderdale. The room was reasonable, better than the one Dave Moran heard them in, and they were positioned well laterally but cold have been pulled out another foot or two from the front wall. In the narrow mode the sound was acceptable but the imaging was not as solid as I am used to. The soundstage was limited to the speaker separation and was good but not live sounding. In the wide mode, I immediately heard the ambience go outside the speakers and the imaging started solidifying up. In the omni mode, it got very interesting, with ambience all across the room width, and individual instrumental images more specific and solid and placed in a 3D space with some depth. I couldn’t play a CD that I brought along because their only source was streaming audio from a digital player and Spotify. Bottom line, the narrow mode was definitely NOT my preferred setting, and the wider it got the better it got. This should be obvious to any listener!
Ivan Bach says:
Hello
I have beolab 5 speaker
I am very satisfied …
but i would like to buy beolab 90
they are a little expensive for me
will there come a loudspeaker between these two
5 and 90 ??? for a reasonable price, in the near future
Beolab 5 costs 21.500 euro
Beolab 90 costs 67.200 euro
Pascal says:
great clip and good summary of the loudspeakers qualities! I enjoy the BeoLab 90s every day! Only downside: you have to live with some audiophile envy… ;-) Nothing comes close to sound quality and its amazing design! Thanks again, Pascal :-)
Gary Eickmeier says:
Geoff please have your engineers write to me. Please. None of your radiation patterns are correct for the goals that you – that we all seek.
Briefly – if you have heard about the DBX Soundfield One and how it was developed, that is the frontal radiation pattern that you need for good imaging all across the room. The technique is called distance/ intensity trading and it determines the lateral localization part of imaging. Do that with the front drivers.
The part of the radiation pattern that determines depth and spaciousness is the rear half. It needs to be cast to the rear at 30 to 45 degrees to each side to get the delayed lateral reflections moving and to maintain the central imaging in the depth dimension. Furthermore, it needs to be stronger than the frontal radiation to cause a harmless image shift to the rear, to get the imaging outside the actual speakers and make them disappear as obvious sources of the sound. That is what causes transparency of imaging.
You then have a much simpler design that achieves ALL of your objectives that you are trying to handle with hundreds of complications and it does it with one design. The technique, or theory, works best with specular reflectivity from the walls near the speakers, but high end customers would be willing to remodel their audio rooms however necessary to get the most out of the design and it would work quite well in most other rooms as well. The speakers must be positioned 1/4 of the room width in from the side walls and an equal amount out from the front wall to achieve perfectly even imaging all across the front of the room.
Gary Eickmeier
Lakeland, Florida
Mr10percent says:
Gary,
Seems to me you got some great ideas for a world-class loudspeaker system. Why don’t you design, build and market your concept yourself?
I don’t think Bang & Olufsen will be interested in your ideas to be honest. I don’t think they will change their thinking on the BL90 after 12years of development. You are as they say a little late to this party. Maybe Wilson, B&W or Sonus et al may be more interested?
geoff says:
Hi Gary,
Thanks for your continued enthusiasm in following the information on my website.
As I said before, I think that we have to agree to disagree. The loudspeaker directivity recommendations that you’ve outlined repeatedly in your comments here are in direct contradistinction with the intention and philosophy behind BeoLab 90’s “Narrow” mode. However, as I described in a previous reply, if you prefer to have a higher level of reflected sound from a loudspeaker, this can be currently achieved either by using BeoLab 90’s “Omni” or “Wide” modes – or by using the Beam Rotation feature to direct the main axis of the radiation away from the listening position as a method of adjusting the direct-to-“reverberant” level ratio to suit your preference (I use the word in quotation marks, since a small room can not be said to be truly reverberant).
As I also mentioned before, I suggest that you have a listen to BeoLab 90. I fully expect that the “Narrow” mode will not be to your taste, however, it might be that the other modes are more similar to your preferences.
I would also like to request that we bring this debate/discussion to a close. It seems to me that we opposing viewpoints not only regarding the desirable directivity pattern of a loudspeaker, but methods of its implementation, and I doubt that either of us will convince the other to change his mind.
Sincerely,
– geoff
geoff says:
Hi Pascal,
Great to hear that you’re still happy with your loudspeakers. Thanks very much for the comment! :-)
cheers
– geoff
Gary Eickmeier says:
Geoff – I will let it go if you don’t want to communicate with me in private Email, but I have just one last question. How much of your 12 year project was devoted to the question of what radiation pattern should we want?
geoff says:
Hi Gary,
Thanks.
To answer your last question: Of course there is no way to tell how many hours of the BeoLab 90 development process were devoted to the design of the various directivity patterns. However, I would estimate that roughly 2 years of the 8-year development process were spent specifically on this. However, that’s just the time spent on the BeoLab 90… The general design of loudspeaker directivity and its implications at the listening positions, not only spatially, but also temporally and timbrally, have been perennial topics of discussion at Bang & Olufsen going back to the 1950’s. A short history of this was exactly the topic of an article that I co-wrote for this book.
The one issue that is not touched on in there, but is also worth noting (and has been discussed at B&O as well as at least one other manufacturer, based on historical AES publications) is the relationship and implications of loudspeaker directivity and noise/distortion. To give just one simple example of this: if you have a loudspeaker driver that behaves pistonically for its linear components, but exhibits “breakup” in higher frequency bands, you can have a situation where the non-linear products are much louder than the linear output in that frequency region when measured off-axis. In other words, the frequency-dependent directivity of a loudspeaker driver’s (unwanted) distortion artefacts is not necessarily the same as it is for its desired output – and this has a potentially worrisome effect on its off-axis response (and therefore the reflected response). Of course, this is further complicated by diffraction caused by the surrounding baffle. But, as I said, this is just one example…
I still owe you the bibliography listing the papers from the Archimedes project – I haven’t forgotten – but this week has been a little busy… sorry I’m late with delivering on that.
Cheers
-geoff
Gary Eickmeier says:
Geoff –
You don’t “owe” me anything but I would appreciate some of the biggest findings of the Archimedes project. Also, when you say you wrote the pertinent article on loudspeaker directivity in the “100 Years” book, which pages would that be? I would download and print them out if I knew.
Gary
David Moran says:
GM, I owe you are report of the BAS BL90 meeting and audition at the local dealer, plus informal measurements. V nice even with a most suboptimal room. But I have misplaced our email re concert A error, so can you kindly resend me your contact info privately? tnx, –David
Gary Eickmeier says:
Geoff, I have now heard the BL90 at your Gulfstream dealer down near Ft Lauderdale. The room was reasonable, better than the one Dave Moran heard them in, and they were positioned well laterally but cold have been pulled out another foot or two from the front wall. In the narrow mode the sound was acceptable but the imaging was not as solid as I am used to. The soundstage was limited to the speaker separation and was good but not live sounding. In the wide mode, I immediately heard the ambience go outside the speakers and the imaging started solidifying up. In the omni mode, it got very interesting, with ambience all across the room width, and individual instrumental images more specific and solid and placed in a 3D space with some depth. I couldn’t play a CD that I brought along because their only source was streaming audio from a digital player and Spotify. Bottom line, the narrow mode was definitely NOT my preferred setting, and the wider it got the better it got. This should be obvious to any listener!
Ivan Bach says:
Hello
I have beolab 5 speaker
I am very satisfied …
but i would like to buy beolab 90
they are a little expensive for me
will there come a loudspeaker between these two
5 and 90 ??? for a reasonable price, in the near future
Beolab 5 costs 21.500 euro
Beolab 90 costs 67.200 euro
geoff says:
Hi Ivan,
I’m sorry, but I am only able to discuss the technical aspects of Bang & Olufsen products in the existing portfolio.
Cheers
-geoff