I can simulate separate enclosures or Keele's speakers. I need to have all dimensions, shading values, etc...Generally(but not allways...), my results are quite near from Don Keele's (or Doug Button) published results.
I commited the software, it is not available yet (there is no closed-form solutions for finite arrays, so you have to use BEM/FEM methods which are far from real-time contrary to my software which does real time auralization)
No, I don't use FEM/BEM at all : those methods couldn't calculate responses in real time (by real time, I mean ie to be able to move listening point while playing sound through simulated array).
I don't use any Green function. The simulated acoustic radiation is a brute force approach based on Huygens-Fresnel decomposition of sources and real-time superposition of all radiations at listener place.
I can add diffraction effects but it adds tenths or hundreds of virtual sources per cabinet depending on cabinet dimensions. I can do it for small arrays but for arrays of 10 or more loudspeakers, adding it to all the virtual sources of each loudspeakers, it may run to CPU limits avoiding real time simulation.
I can add diffraction effects but it adds tenths or hundreds of virtual sources per cabinet depending on cabinet dimensions. I can do it for small arrays but for arrays of 10 or more loudspeakers, adding it to all the virtual sources of each loudspeakers, it may run to CPU limits avoiding real time simulation.
Why not do it here ?
Design #1 uses 8 P7's per side. Each driver in a sealed rectangular MDF enclosure 5/8"(.016m) thick.
Internal measurements on this common enclosure is 9 1/4"(.235m) length, 4 1/2"(.114m) height and 4 1/2" width. Very minimal internal stuffing.
Here is the best pic I have of this setup. Please ignore the tweeter in the middle. I estimate the angle about 15degrees between each enclosure.
Internal measurements on this common enclosure is 9 1/4"(.235m) length, 4 1/2"(.114m) height and 4 1/2" width. Very minimal internal stuffing.
Here is the best pic I have of this setup. Please ignore the tweeter in the middle. I estimate the angle about 15degrees between each enclosure.
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Design #2 uses 12 P7's per side.
Each driver in a sealed PVC enclosure. Some stuffing, loosely packed. I choose it because of the rounded cylinders 2nd best diffraction characteristics. 2nd only to the sphere enclosure.
Front and rear PVC endcaps are rounded internally and externally. Volume is estimated @.1cuft(2.8l). Internal dimensions are approx: 7"(.18m) length x 5.5"(.14m)
Each driver in a sealed PVC enclosure. Some stuffing, loosely packed. I choose it because of the rounded cylinders 2nd best diffraction characteristics. 2nd only to the sphere enclosure.
Front and rear PVC endcaps are rounded internally and externally. Volume is estimated @.1cuft(2.8l). Internal dimensions are approx: 7"(.18m) length x 5.5"(.14m)
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Consider this a shootout between cylinders vs. rectangles in a configurable line array. I need some help because while transitioning from 8 rectangles per side to 12 cylinders per side (and changing from carpet to vinyl flooring simultaneously), the sound difference is quite different. I'm not what sure to blame, so need some help 
8 New P7 drivers do have about 50hrs break in with still no appreciable difference in sound.
Thx to jlo for tackling this! And everyone else for tolerating my condtition.
8 New P7 drivers do have about 50hrs break in with still no appreciable difference in sound.Thx to jlo for tackling this! And everyone else for tolerating my condtition.
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.....the sound difference is quite different. I'm not what sure to blame, so need some help
Looking at your pictures it seems the 8 drivers per side system have subwoofer support and the 12 drivers per side system run full range, that difference can have big influence for many reasons.
If hope is they change by time as reported by many MA fans and the change is always reported the lucky way that they get better and better with particular change and not the other way around, then suggest try make some research into subject and measure impedance and response over time because there is also the possibility that one just got used to new sound stage rather that they change much, say this because been using brand myself in past and don't agree the hype other than be gentle to them the first week or so because manufacture tell us and recommend it.
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While that may be true, comparing a new driver to a broken in one shows that the drivers are improving. Which one would expect given that the spider designer has specified tha the spider needs time to break-in/loosen up not to mention the surround and cone settling in.
dave
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