Those sure are green! (see the last page).
I've often thought about a similar rig, but am pretty happy now with the bass using only a 416 per side.
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Those sure are green! (see the last page).
I've often thought about a similar rig, but am pretty happy now with the bass using only a 416 per side.
Yeah, the 'blind leading the blind' to my way of thinking............. Anyway, for those that believe a vent of any tuning is superior performing to a properly designed/implemented (mid) woofer/compression horn A7 conversion, then to allow it 'to be all it can be' at least use multiple passive radiators [PRs] same as Olson did on his LC-9A 'A7' variant to tune it except mount them on opposing sides to ~ cancel out their high excursion rocking vibrations.
GM
Yeah, I like green but I don't think I could take those for long.
My guess is that the section of the box used is too small for the 18". But that's just a guess. It still ought to add some good grunt.
Dunno, don't care, it's the concept they're trashing that I take exception to........
GM
Bfish, tell us more.
The best part of an 825/828 box is the front horn. From there it goes downhill. The output starts to roll off aound 180Hz where the horn unloads. Doesn't matter if you tune the reflex to 60, 40, 20, or even 10, the reflex output is way less than the horn, and being forced to play that low with little acoustic load soon compromises an underhung 15 with excursion limits.
Dividing the box fixes those issues. There's less than 2 cu/ft for the 15 (assuming full-width baffle sealing off flare volume), which, when fine-tuned, matches the reactive load of the horn, raises Fb, limits the 15 to just what it does best (in this app), and lets it do a lot more of it. The ~7.6 cu/ft left below just happens to be "perfect" for a 2245 (and several other 18s). Biamp the combo and bring the LF up to where it needs to be; at the same output level as the front horn. No brainer.
I'm using 2 each simply because I had them, but have no room for the 4 external 7ft boxes they'd be ideal in. Sure, they won't be flat to 27 Hz in that volume like one would (BR), but they will be sealed so I can EQ it flat wherever they are. I just hope they can keep up...
The project went on hold some time ago because I got frustrated being unable to get a satisfactory oak finish on the extra layer of ply I skinned them with (can't veneer with the 3/4 round edges and rounded corners). Screw that. Now I'm just p'd off enough to paint over the stain and get them in action before I get too old & frail to move them around.