Directivity of side by side woofers

Here is how to improve such system polars and directivity control (at least in the sim) as well as macho points, use three woofers! The middle one seems to even out some of the lobing around 1kHZ (if it mattered anyway) while increased c-c of the outer drives get directivity control down low.

That would make six woofers for a stereo system, should be plenty :D
 

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Here are measured plots for a JBL 4838 twin 15 Cinema enclosure. They are used with the woofers in a vertical placement. For a horizontal array just use the vertical polar's. You can clearly see issues but these are typically used with a horn dropped on top. Have to wonder just how audible the notches are in actual use.

I have heard several systems using these boxes and as ugly as it may look they sounded just fine.

Everest is a 2 1/2 way.

Rob :)
 

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^ if you checkout post #37 attachment the toe out setup seem to combine into nice wave front at least up to the ~700Hz test. The intensity seems to be quite uniform with wide dispersion. The toe in setup makes more distinct main lobe so narrower pattern overal. But jeah even the sims have lots of simplification baked in so :) I think I've seen examples done both ways, from memory the toe in situation is quite rare though. Some high end products seem to have it (on the vertical axis). Most if not all big monitors using 15" side by side have them flat or toed out? In fact it is quite hard to google up images of these dual woofer systems, there is much more stacked vertically than in the horizontal configuration.

Here is someone building augsburger type thing, with toed in woofers. Some measurements of dual woofer setup in post #49, images and what not later in the thread.
Old School Studio Monitor Build | Page 3 | AVS Forum

Surely a system like this is cool looking but not sure if it is something one would want or need for sound quality. If they were good, they'd be everywhere instead of stacked drivers?:)

I think both inward and outward angling has merit since they have both been used in studio monitors. It probably works well if the crossover frequency and angle are in 'sync'.

Your simulations make it alot easier to understand how this works, impressive stuff :up: