"Crossover Design for New Project"

[GM]

Horizontal woofs would "flip" the directivity, necesitating a different XO point (among other things), one that would defeat much of the reason for using a 288.

Defeat ???

GM

[bfish]

Yeah, the power-hog aspect of parallel woofs is exactly why I suggested impedance matching the pairs.

4 box MTM meant a box for each 416. I figured whether or not you boxed the 511s in the middle was an aesthetic matter.

By "defeating" the reason for a 288, I had in mind the 288 advantage of being able to lower the XO point, which seems to conflict with a directivity match for horizontal woofs. IOW, if you're crossing much higher than 500Hz, why not take advantage of the extra BW a small format offers and fuggetabout the PITA tweets?

However, I hadn't considered corners. When the room placement limits everything to 90 degrees, horizontal/low XO makes sense.

[GM]

4 box MTM meant a box for each 416. I figured whether or not you boxed the 511s in the middle was an aesthetic matter.

By "defeating" the reason for a 288, I had in mind the 288 advantage of being able to lower the XO point, which seems to conflict with a directivity match for horizontal woofs. IOW, if you're crossing much higher than 500Hz, why not take advantage of the extra BW a small format offers and fuggetabout the PITA tweets?

However, I hadn't considered corners. When the room placement limits everything to 90 degrees, horizontal/low XO makes sense.

Ah! I was viewing it as a single speaker system. Well, there's sonic reasons for boxing in the horn if XOing down near/at the horn's lower usable limit.

Hmm, long ago I worked out 'close enough' (for me anyway) polar matching XOs and came to the conclusion that dual horizontally opposed 15" drivers were a better match to a 511/500 Hz than vertically same as the 9844 Vs Malibu for the 811/800 Hz. IOW, all else equal, going 'wide' dictates a lower XO point which brings us back to our point of why 'waste' a 288 on a higher XO point in a non-prosound app unless you have a low enough efficiency LF system that you risk over-driving it below the XO point?

Actually, assuming the speaker is designed to fit the corner, letting it do the pattern control negates the horizontally opposed driver layout's 'virtual corner' advantage, but there's still the acoustic center differences that makes it the 'no brainer' choice for me if space permits.

GM

[bfish]

...long ago I worked out 'close enough' (for me anyway) polar matching XOs and came to the conclusion that dual horizontally opposed 15" drivers were a better match to a 511/500 Hz than vertically...

Based only on the DI plot for vertical 15s below, it appears the opposite to me. At 500Hz, the woofs are at 60 degrees (vertically, which becomes horizontal if you flip them)...

IOW, all else equal, going 'wide' dictates a lower XO point...
GM

I'm not getting it. Not trying to be obstinate, just trying to understand.

[GM]

Understood, when I saw that plot I could see it coming round the bend........... Frankly, I think the plot is another of those many marketing errors we found/joked about some years ago, but will take another look at it when I'm not so preoccupied.

GM

[bfish]

Understood, when I saw that plot I could see it coming round the bend........... Frankly, I think the plot is another of those many marketing errors we found/joked about some years ago, but will take another look at it when I'm not so preoccupied.

GM

Lacking a comparable, I'm inclined to agree, except for the fact that it's fairly well in line with what (little) I know of line array theory.

[bfish]

Lacking a comparable...

OK, the 9845 (dual horizontal 416s, 500Hz) DI plot throws a wrench in the works;

http://alteclansingunofficial.nlenet...rs/TL_201A.pdf

(skip to PDF page 18)

[Panomaniac]

Agreed. Not an easy build, but should be a great corner set-up.
As you know I'm a fan of the Onken box, which was derived from the Jensen Ultraflex.

From the Altec plots I see the 511 averaging about 75 deg. horizontal toward the bottom end. A single woofer or 2 stacked should be close to that in the 500-700Hz range, right? Of course it will widen out to 360 at some point, unless it's in a corner.