No No, just did a super spontaneous fast sweep in the situation i have at the time, my daughter and 4 of her friends was in the way and was making the bed near the speakers. ( between speakers and listeningpoint, in the feld if you say so)
Mic maby 25 grades at left side of center Left speaker so no L and L or LR measure, just a bad L ( but sound is still so good ) when you listening "from the side"
Hope i have "the power" to do some more mesaurements even if im so happy with the total sound from listeningpoint
It´s real interesting to se a curve after you know you really like the sound.
What about placing the cardioid woofers on the side? Thats what I tried to sim in vituixcad. I liked the pattern better than a rear facing woofer, but I couldn't see how to view 180degrees from the listening point. I don't think Vituix can do it.
This ripole thing has got my interest... I've got about +/-3db Trend line from 70hz down to 20hz now. Nasty sharp null at 80hz but it was there before I removed the rear panel. Its hard to say that anything more than the fuller FR is improving my experience. Ill have to a/b with its twin thats still sealed. I think that an active set up will have the potential to be more potent in effect because of the fine tuning of phase... I wonder if this directivity is the reason behind it...
Directivity of the loudspeaker directly affects the modal behavior of the room. Directivity is sometimes a reflection of money spent, and size. "Dips and peaks are at same position and as severe as before." - That's incorrect, I just changed my modal character by taking off the rear panel, creating a dipole polar radiation, the Modal behavior at the listening position, changed significantly, Sincerely Directivity. Size affects directivity, money will pay for larger horns, waveguides, drivers, large baffles, dsp and additional woofers, for active cardioid, possibly flush mounting into the wall....
No, we can also, do things to lessen the rooms involvement, it is something that will cost more time/money usually, due to more parts, ie waveguide, horn, cardioid, larger baffles, larger drivers, etc, all things that Increase directivity, and lessen the rooms involvement. The whole principle of multisub is independent of the room, it increases SQ by improving model performance, and it cost more money. Sitting Closer is free.
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I don't know about showing off, I look for critique. Also, I the honesty, as in sharing info freely, which I've shared multiple REW files in the past of my horn and what not. Funny enough, people are not always as interested, I think we are the nerds or something lol
On that note. The waterfall is my new favorite view. If you get the chance, share some of those views. When I get a chance I will take and share measurements displaying my FR as I move away from the speaker.
Hi, you are working with the room
The room is still there and the modes due to its dimensions are the same they've always been, they are not affected by speaker directivity, only moving walls or building new ones would change it. However you are right that changing speaker pattern will change outcome everything else kept the same. You still probably want to move and rotate the speaker around to find best spot that works with the room best.Monopole on a big baffles, yeah affects things when size is comparable to wavelength. Since "problems" are room sized wavelengths we need room sized solution to really affect it. Anything smaller has less and less effect on the outcome. Lowest mode wavelength in a room is twice the longest dimension. If it is 5m then 10m is wavelength of most problematic dip if you happen to sit at it. Physical object that has any effect on sound propagation needs to be something like tenth of wavelength, square meter, but the influence on 10m wavelength sound would still be much. Sure, for 1m long wavelength effect of it would very great. Build another wall and you've just changed things. Or use two (any size) monopoles spread 5m apart and the system size is now half wavelength and you'd gain some control over the issue.
Dipole and cardioid work probably great when you have enough Sd available so that enough system SPL capability is still there, and you sure do
A Double Bass Array is also a good solution for minimizing the room's influence. It requires a lot of EQ tweaking, but the result can be very impressing.
https://www.diyaudio.com/community/...ssibly-affordable.392381/page-12#post-7202266
https://www.diyaudio.com/community/...ssibly-affordable.392381/page-12#post-7202266
https://www.diyaudio.com/community/...d-and-possibly-affordable.392381/post-7202266
This link works for StigErik's post for those with non-standard posts per page settings like myself. You'll always get the correct link at the post number.
This link works for StigErik's post for those with non-standard posts per page settings like myself. You'll always get the correct link at the post number.
looks very impressive! What is the issue with the EQ tweaking? Couldn't you have used software to do the eqing for you?
What exactly are the principles of a DBA might be a good question. This isn't just simply multisub, this is using rear subs to cancel out and add where necessary ? The only knowledge I have of DBA consist having a symmetric positioning, front vs rear, and then the woofers are time aligned to the same position in space where the listener is, aka, sweet spot. I read about this a long time ago, so I could be mistaken.
Hmm quick read through, TLDR;
"Many different multi-sub approaches could now be tried out but let us focus on the so-called Double Bass Array method. Here, the strategy basically is to turn the room into a tube. Tube acoustics is a little more involved than room acoustics (and a good topic if you want to really understand room acoustics better), but there is one major thing to understand: “The plane wave will always propagate”. Tube modes differ from room modes in that the former type really exist at all frequencies at once and will either propagate if excited above an associated modal frequency or die out as an evanescent wave below it. The only wave that will always propagate is the plane wave, and one way to achieve a propagating plane wave is to excite both the front wall and the rear wall in a pistonic-like fashion as shown in the animation below."
This was animated, but this is the following post to give context; "The subs on the second wall are supposed to "remove that wall" so theres no reflection? So there active absorbers"
And the response; "Yes they effectively works as an absorbing layer. The rear wall has a specialised displacement that follows the displacement that the travelling wave has and would have were the room infinitely long. But an out of phase sub next to one of the subs will be a very different situation where you create a dipole. The point of the DBA is to create the travelling wave in a confined space.
The wave only travels in one direction and so no modes are excited in the idealised tube situation. Looking at higher frequencies you will see that a finite number of subs will not be enough and modal behaviour will become more important, but you will be crossing over to your mains anyway."
Imagine combining this with Active cardioid mains!!.... I think the question is, regarding the Set up of this type of DBA (because think there are multi DBA approaches) couldn;t something like ACourate or Audiolense create the filters pretty easily?
"Many different multi-sub approaches could now be tried out but let us focus on the so-called Double Bass Array method. Here, the strategy basically is to turn the room into a tube. Tube acoustics is a little more involved than room acoustics (and a good topic if you want to really understand room acoustics better), but there is one major thing to understand: “The plane wave will always propagate”. Tube modes differ from room modes in that the former type really exist at all frequencies at once and will either propagate if excited above an associated modal frequency or die out as an evanescent wave below it. The only wave that will always propagate is the plane wave, and one way to achieve a propagating plane wave is to excite both the front wall and the rear wall in a pistonic-like fashion as shown in the animation below."
This was animated, but this is the following post to give context; "The subs on the second wall are supposed to "remove that wall" so theres no reflection? So there active absorbers"
And the response; "Yes they effectively works as an absorbing layer. The rear wall has a specialised displacement that follows the displacement that the travelling wave has and would have were the room infinitely long. But an out of phase sub next to one of the subs will be a very different situation where you create a dipole. The point of the DBA is to create the travelling wave in a confined space.
The wave only travels in one direction and so no modes are excited in the idealised tube situation. Looking at higher frequencies you will see that a finite number of subs will not be enough and modal behaviour will become more important, but you will be crossing over to your mains anyway."
Imagine combining this with Active cardioid mains!!.... I think the question is, regarding the Set up of this type of DBA (because think there are multi DBA approaches) couldn;t something like ACourate or Audiolense create the filters pretty easily?
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Made a couple of measurements tonight, and I have a 15 dB dip between 160 - 500 hz (which feels weird)
And i must go to the bottom with it, maby start over with midrangedriver measurement without xover at the actual baffle in the room.
Did some near field measurements on 1 of the woofers also at different volumes.
My back hurts like hell now after crawling around.
And i must go to the bottom with it, maby start over with midrangedriver measurement without xover at the actual baffle in the room.
Did some near field measurements on 1 of the woofers also at different volumes.
My back hurts like hell now after crawling around.
