Find the longest center to center [ctc] spacing to find the 1 WL XO limit with the understanding that it ideally needs to be a 1/4 WL.
For example: it's 20 cm, then 34400/20 = 1720 Hz 1W or 430 Hz 1/4 WL.
Or if 1800 Hz is the limit, then 34400/1800 = 19.11 cm or 4.78 cm.
Note that normally 1/3 WL is acceptable, most commonly used.
GM
For example: it's 20 cm, then 34400/20 = 1720 Hz 1W or 430 Hz 1/4 WL.
Or if 1800 Hz is the limit, then 34400/1800 = 19.11 cm or 4.78 cm.
Note that normally 1/3 WL is acceptable, most commonly used.
GM
I believe probably in the original equation they assume a point source. At s distance L apart. However in this case I believe it is a full cone I don't think the equation is valid anymore. All the cones are moving together as if it is one big diaphragm, I don't there will be a combing effect...
Need to draw a diagonal line.
Again, I posted: "Or if 1800 Hz is the limit, then 34400/1800 = 19.11 cm or 4.78 cm."
So based on a 4.8 cm ctc spacing, you're limited to two rows of three at ~0.794 WL ctc.
GM
It's valid TTBOMK. They're moving as one down low, but as the frequency increases they become increasingly more independent of each other with obvious combing effect above the ~1 WL point, though this is so dependent on each human's hearing acuity, room, listening distance, etc., like a MTM or line array that it's strictly a guideline.
That said, I've wondered if an average is a better way, i.e. [4.8*9.6]^0.5 = ~6.79" in which case we could just fudge a bit and use 2 rows of four [19.11/4.8 = 3.98].
GM
Alcoholic musings 
referring to a type of array tuning, something you may find of use.
frequency shading - Google Search
GM
referring to a type of array tuning, something you may find of use. frequency shading - Google Search
GM
Multiple drivers create comb filtering. As our ears are in the horizontal plane, we are much more sensitive to comb filtering from multiple sources in the horizontal plane.
If I had to use multiple drivers in a horizontal plane I would do it like Tecton.
Maybe mount he middle driver or middle line of drivers a little bit forward so that the driver frames overlap and CTC distances gets smaller, and this will also influence directivity. (getting wider)
About the tecton array Help Understanding Tekton Tweeter Array Schematic?
If I had to use multiple drivers in a horizontal plane I would do it like Tecton.
Maybe mount he middle driver or middle line of drivers a little bit forward so that the driver frames overlap and CTC distances gets smaller, and this will also influence directivity. (getting wider)
About the tecton array Help Understanding Tekton Tweeter Array Schematic?
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I do use comb filtering as an advantage by putting them in a vertical line to narrow vertical directivity so they match a line tweeter like a ribbon, planar or AMT very well. Big advantage of this design is great horizontal off axis response and minimal floor and ceiling reflections.
Every single driver produces comb filtering relative to its diameter that starts at wavelength equal to its diameter; that is what makes the narrowing directivity for the higher frequencies it produces.
Or that is why smaller drivers have better off axis response for higher frequencies.
Great video about line source and line array speakers: YouTube
Every single driver produces comb filtering relative to its diameter that starts at wavelength equal to its diameter; that is what makes the narrowing directivity for the higher frequencies it produces.
Or that is why smaller drivers have better off axis response for higher frequencies.
Great video about line source and line array speakers: YouTube
No need, it's part of the whole; personally ran out of time to post more re layout.
GM
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