4 x 5” FR� flat array ?

I think, judging from earlier posts Norman made, he likes bass but also likes the (single) full range speaker. I guess this would be a way to get more bass out of it (increased power handling) while retaining some of the single speaker qualities (like it's phase behavior).
However, personally I'd find what I suggested here a bit too limited as well. It actually holds up pretty good if one moves up or down, better that the graphs here depict with the nulls in the polar map. In reality they move (up and down in frequency) with changing the height but don't create a null until we are quite a bit higher (*).

Here's an overlay of -100 up to +100 around the average 1m listening height (in steps of 25mm):


(floor and ceiling reflections are -20dB down in this and earlier graphs)

Pretty excellent behavior for an array with this center to center spacing.
The horizontal window will be determined by the (single) driver's off axis behavior, vertically it could use some EQ as this sim didn't use a real driver on a real baffle but more of an idealized flat measuring driver. But if one is willing to do that, there is some potential here ;). It will suffer way less from floor and ceiling reflections than a single driver speaker and it will have quite a bit more power handling too on the bottom end.

(*) an example at 100mm below the assumed listening axis of 1 m:

See how the nulls have moved, but the output is still within the range of the previous graph.


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ah, yes, thank you.

I see where I was off.

I was thinking that. Even if you are equa-distant to top/bottom drivers, then the center 2 would be closer than ideal causing a bit of cancelation.

Yea, I am cursed.
A full range driver fan that wants pounding bass like my double 15 did(F3=30-750hz).

8" at 36" off floor, not enough bass, 8" on floor, not enough bass, 4 x 9", not enough bass, 12" on floor/wall, not enough bass.

That's why I', liking my 4 x 3.5" array some of the time, and use 12" 2-way (horn tweet) most of the time.
I have been imagining two towers lately.
One consisting of nine 8" bass drivers, next to a column of SB65. Repeat on the other side.
Then, maybe just maybe, making them OB.
Power the bass lines/FR lines with DSP hypers, or two amps, using a miniDSP product, like the SDH.
Should be enough bass... :)
Yes it will.

Itis a featureof things like the microTowers (both bipoles and castle) use drivers firing in different directions which makes them more omnidirectionl and room-filling.

No issues withcombing and can be used for BSC.

Scott, Chris, and i have done a number of such configurations, as with everything, one has to keep in mind the compromises.

1 on front, 1 on back, 1 onfront one on top, 2 on the front, 1 on either side. 4, 1 driver each side. 3 drivers, one forward, 2 on back (at an angle, imagine a trianglular, pentagonal, or hexagonal prism as the box).




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It is, i have done considerable mapping of the possibilities. Documane not finished yet.

Any combination of series/parallel wiring has 2 drivers down 3dB from the driver not in series with any others, so only the output of a pair of drivers (ignoring the amplifier output into the load), but this may prove useful in some situations.