I hate to rain on your parade, but having the full range drivers side by side is not the best way to do it. If I remember correctly, someone else did a focused array like you but with 2 nsb drivers wide. He preferred 1 driver wide.
Don't get me wrong, cone area is a good thing. I've wanted to make something like this but never had. It has 16 x 4" drivers and a woofer/sub (crossed I'm not sure where) per side, and it probably has baffle step compensation also. 16 x 4" has close to the same area as an 18".
Norman
Don't get me wrong, cone area is a good thing. I've wanted to make something like this but never had. It has 16 x 4" drivers and a woofer/sub (crossed I'm not sure where) per side, and it probably has baffle step compensation also. 16 x 4" has close to the same area as an 18".
Norman
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uh, yea, that's way different than a focused array (that I recommend so long as there is only one, I mean ONE listener). To me, the keele array would be full of smear, even more than a line array, but I think he is more concerned with directivity and room acoustics. Even panel speakers (to me) makes a guitar seem like it is 6' tall. But Keele uses bessel wiring (lessening the volume of the speakers further from you = less combing = more highs than a flat array).
On a focused array, all the drivers are working all the time. You truly pick up volume, dynamics, and bass compared to a single driver. I recommend it as a way to get more out of a full range driver (adding to excellent intelligibility, point source, less phase shift than most crossovers, and a lack of different materials (tweet to woofer)). With my 4 x 4", I picked up a tremendous amount of backround information watching thx-1138. Someday I may build a big one (like the copernicus 2 in the picture), but my system changes often, and I've been in a home theater mood lately.
Cone area is another stickler for an array. Say I find some really good 4" drivers for $40 each. 4 of them have the same area as an 8", but now with a budget of $160 for an 8", that opens a bit of options with a much less complicated box to build and wiring (especially as you get lots of drivers).
But I certainly cannot argue with the man's accomplishments. That thing is certainly another way for someone to get to audio nirvana.
Norman
On a focused array, all the drivers are working all the time. You truly pick up volume, dynamics, and bass compared to a single driver. I recommend it as a way to get more out of a full range driver (adding to excellent intelligibility, point source, less phase shift than most crossovers, and a lack of different materials (tweet to woofer)). With my 4 x 4", I picked up a tremendous amount of backround information watching thx-1138. Someday I may build a big one (like the copernicus 2 in the picture), but my system changes often, and I've been in a home theater mood lately.
Cone area is another stickler for an array. Say I find some really good 4" drivers for $40 each. 4 of them have the same area as an 8", but now with a budget of $160 for an 8", that opens a bit of options with a much less complicated box to build and wiring (especially as you get lots of drivers).
But I certainly cannot argue with the man's accomplishments. That thing is certainly another way for someone to get to audio nirvana.
Norman
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I hate to rain on your parade, but having the full range drivers side by side is not the best way to do it. If I remember correctly, someone else did a focused array like you but with 2 nsb drivers wide. He preferred 1 driver wide.
Don't get me wrong, cone area is a good thing. I've wanted to make something like this but never had. It has 16 x 4" drivers and a woofer/sub (crossed I'm not sure where) per side, and it probably has baffle step compensation also. 16 x 4" has close to the same area as an 18".
Norman
They are not side by side Norman.
The outer top 8 drivers on each side are the ones using race, those are actively crossed to the inner two rows and the last bottom 5 on the outer sides. I have two Dayton amps going in the box at the bottom, along with the mini-ambio.
I will eq the (top 8) outer drivers that are running RACE to achieve a 2nd order slope (LR) at the drvers fs. Mini ambio has 4 bands peq.
The rest of the drivers will be run off the second amp.
These Dayton amps have a 3rd order low pass....
So if I set the crossover on the amp at say 50 hz, that should get me a -6 at 40 hz because the 3rd order low pass will actually be a 2nd order low pass because the drivers are gaining 6db an octave as they are approaching the dipole (baffle step) if you will.
So, I'm guessing the crossover will end up around 150 hz (LR 2nd order) for both high and low pass. But we will see how that pans out in testing.
The good thing about this configuration is that I can set the low pass on the amp at 50 hz for extension or set it at 100 hz (which will give me a -6 db around 80 hz) for dynamics.
I have an 18" sub coming in the mail for my dipole H frame sub.
That one is going to be called (the singularity)
See the theme I'm going for?
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Well the arc is set to focus at 9 ft, 2.743 meters for you.
So, maybe 8 ft is better for a few inches of vertical movement.
Comb filtering will be above 20 kHz at that angle.
But I'm thinking (through my own observations with my dipole full rangers)
That, it should be set up 9 ft from the back wall, and having the ears at 1 or 1/2 ft away from the wall to have the reflections act as a 2nd ambiopole behind you.....to push pinna cues out to the sides.
Norman Bates wrote :
Keele has done maybe the best study about the Bessel arrays, but what you describe here is more a power tapering, frequency independent Legendre shading as he names it.
The Bessel is the best known and the easiest to approximate, but there are others sequences arrangements as Barker, Quadratic Phase Array, binary maximally-flat, Huffman...
Ok this is just a detail of the story. I have very good hope that MT can get good results from his concept, but maybe not straightforward. He has many mapping possibilities to try independently of the mini ambio settings, it's a wide field of experiments.
The only limitation I can see for the sake of research is that he has been choosing "only" 4 vertical rows of drivers, opting for 5 would have give the opportunity of further development.
Keele has done maybe the best study about the Bessel arrays, but what you describe here is more a power tapering, frequency independent Legendre shading as he names it.
The Bessel is the best known and the easiest to approximate, but there are others sequences arrangements as Barker, Quadratic Phase Array, binary maximally-flat, Huffman...
Ok this is just a detail of the story. I have very good hope that MT can get good results from his concept, but maybe not straightforward. He has many mapping possibilities to try independently of the mini ambio settings, it's a wide field of experiments.
The only limitation I can see for the sake of research is that he has been choosing "only" 4 vertical rows of drivers, opting for 5 would have give the opportunity of further development.
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It's not, not at all - as surprising as that may seem. I heard it from 5cm to ~30m and it's cohesive. The concept works better than any other line array I've heard.
Well, I really don't know what this means.
Mid-side matrix like pro-logic?
Anyway, I can always build another one!
I don't know much about designing algorithms for digital filters, so if you have some thoughts on those, feel free to explain further.
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Only the top 8 of the outer sides use RACE
2 series 4 parallel = 4 ohms
I can choose to wire the rest for mono or stereo
36 drivers
Mono will be 6 series 6 parallel = 8 ohms
Stereo 3 series 6 parallel = 4 ohms
Thanx Poldus,
I'm wrapping the whole baffle and support rails in grill cloth so it will look like it's slicing through the box.
I'm using 2 of these amps...
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=300-812
2 series 4 parallel = 4 ohms
I can choose to wire the rest for mono or stereo
36 drivers
Mono will be 6 series 6 parallel = 8 ohms
Stereo 3 series 6 parallel = 4 ohms
Thanx Poldus,
I'm wrapping the whole baffle and support rails in grill cloth so it will look like it's slicing through the box.
I'm using 2 of these amps...
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=300-812
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