Oh, I see - I didn't know the abbreviation 
LFE project will be another thread, but I've been leaning towards building a lilmike "lilwrecker"... there's not much "little" about it! I have not looked into the BFM designs much, maybe scanned a few ideas months ago when I started digging into this project as a whole.
Another thing I forgot to mention about the sealed box for the PA460 is that 3/4" plywood does not seem to be enough... I did more bracing in this box than I did for the ported, and there is still quite a bit of vibration on the outside when you crank it up. I may be losing some quality of bass there, and might be introducing some noise from the panels vibrating as well. So, thicker plywood next time, or maybe double 3/4" panels all around? This stuff gets heavy! Also of note is that the 3/4 OSB seems quite a bit stronger in this regard.. Despite being splintery awful stuff to work with at times, it seems to be a better material for bass heavy speakers (though it's heavy as hell too), especially if you were going to veneer or carpet the box anyway.
LFE project will be another thread, but I've been leaning towards building a lilmike "lilwrecker"... there's not much "little" about it! I have not looked into the BFM designs much, maybe scanned a few ideas months ago when I started digging into this project as a whole.
Another thing I forgot to mention about the sealed box for the PA460 is that 3/4" plywood does not seem to be enough... I did more bracing in this box than I did for the ported, and there is still quite a bit of vibration on the outside when you crank it up. I may be losing some quality of bass there, and might be introducing some noise from the panels vibrating as well. So, thicker plywood next time, or maybe double 3/4" panels all around? This stuff gets heavy! Also of note is that the 3/4 OSB seems quite a bit stronger in this regard.. Despite being splintery awful stuff to work with at times, it seems to be a better material for bass heavy speakers (though it's heavy as hell too), especially if you were going to veneer or carpet the box anyway.
Put heavy weight on top, it may require mass quantities to find the point of diminishing returns and expect needing at least what the speaker weighs: High Efficiency Speaker Asylum
Metal 'cabs' much more: High Efficiency Speaker Asylum
The easiest alternative for the DIYer if not using concrete or similar is to make it so rigid its resonance is well outside the device's passband, so below ~250-500 Hz [depending on who you ask], better to make cabs rigid enough to push it as high as ~ 1 kHz and above it, massive enough to push it down to as low as < ~100 Hz.
GM
to find the point of diminishing returns and expect needing at least what the speaker weighs: High Efficiency Speaker AsylumMetal 'cabs' much more: High Efficiency Speaker Asylum
The easiest alternative for the DIYer if not using concrete or similar is to make it so rigid its resonance is well outside the device's passband, so below ~250-500 Hz [depending on who you ask], better to make cabs rigid enough to push it as high as ~ 1 kHz and above it, massive enough to push it down to as low as < ~100 Hz.
GM
Thanks GM, I had forgotten to try mass loading it. There's one of the 30 lb Fisher tower sitting on top of it, but I suspect the woofer cab weighs around 75-100 lbs with driver. I'll see if I can't dig up a few weight plates, or similar to stack on top.
I was certainly going for rigid construction to not have to deal with the panels flexing, but maybe didn't account for the (presumably) higher cabinet pressures due to it being sealed. Before I mounted the driver, the other 5 sides sounded pretty stiff when whacked with a mallet. I think the OSB may actually be a better material in this regard. At least these are "just" the prototype boxes.
Jesse
I was certainly going for rigid construction to not have to deal with the panels flexing, but maybe didn't account for the (presumably) higher cabinet pressures due to it being sealed. Before I mounted the driver, the other 5 sides sounded pretty stiff when whacked with a mallet. I think the OSB may actually be a better material in this regard. At least these are "just" the prototype boxes.
Jesse
DCX2496 should be here today/tomorrow...
In the mean time I haven't done anything else but listen to the two cabinet designs. I still think the sealed is preferable for most music, but the larger ported box isn't objectionable at all. And the larger ported box is pretty killer for movies, with more output down low.
Running the two cabinets at the same time increases the volume of course, but it seems to increase the "punch" even more. Maybe what I'm calling punch is just room pressurization. I can fade left/right and listen to each box independently, but their total punch together seems to be more than 2x just one of either box. Soundwise, they seem to complement each other pretty well, with overlapping strengths/weaknesses.. If only part of my brain didn't demand L/R symmetry..!
I watched the movie "Bolt" last night and cranked it up to 11, and the LF parts were pretty impressive with just the PA460s (lacking an actual subwoofer). The first 15 minutes or so have some pretty heavy stuff. I suspect the ported box was doing most of the heavy lifting there, as much of it was rumbly/boomy stuff. But also some punchy/fast explosion stuff. It all sounded pretty good, though I suspect I was taxing the woofers pretty hard mechanically - I'll have to try it again with the lights on with no one home to watch the excursion.
Even the wife seemed to enjoy it!
Jesse
In the mean time I haven't done anything else but listen to the two cabinet designs. I still think the sealed is preferable for most music, but the larger ported box isn't objectionable at all. And the larger ported box is pretty killer for movies, with more output down low.
Running the two cabinets at the same time increases the volume of course, but it seems to increase the "punch" even more. Maybe what I'm calling punch is just room pressurization. I can fade left/right and listen to each box independently, but their total punch together seems to be more than 2x just one of either box. Soundwise, they seem to complement each other pretty well, with overlapping strengths/weaknesses.. If only part of my brain didn't demand L/R symmetry..!
I watched the movie "Bolt" last night and cranked it up to 11, and the LF parts were pretty impressive with just the PA460s (lacking an actual subwoofer). The first 15 minutes or so have some pretty heavy stuff. I suspect the ported box was doing most of the heavy lifting there, as much of it was rumbly/boomy stuff. But also some punchy/fast explosion stuff. It all sounded pretty good, though I suspect I was taxing the woofers pretty hard mechanically - I'll have to try it again with the lights on with no one home to watch the excursion.
Even the wife seemed to enjoy it!
Jesse
Summing separate systems is doubling [+3 dB], though room gain can be more, especially since in your case each speaker is located next to a different set of added room cavity resonances and why comparing ported to sealed in your room is somewhat compromised unless you also swap them end to end.
Once the final alignment is chosen you may need to adjust them individually to get as near identical response in mono.
GM
Once the final alignment is chosen you may need to adjust them individually to get as near identical response in mono.
GM
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Update, but not really:
Well, mentally a few weeks later, physically a while longer... I've still been around time to time but just reading. Kids, moved house/shop to new house & building new shop... have not had time for anything!
Finally got things set up in the basement at the new place and wow... I picked the worst room ever to use as a movie/listening room apparently, as the whole lower end of the frequency spectrum gets soaked up by crappy thin paneling on the walls and there seems to be a null spot right where you want to sit. Ugh. It sounds terrible, everything sounds terrible. Now I miss the sound I had in the previous house, which I didn't think was great, but...
The kids knock over or destroy anything I put in the living room with them, so I'm back to square one for a bit - rather not move my stuff up there for them to wreak havoc on.
For now, I may just go back and build a set of ported boxes for some A10.3s, or something similar and small to enjoy tucked away on a shelf somewhere else in the house. In the mean time, finish building my shop, fix a broken track miata, and then finally build the matching pairs to the Fane 12" and 18" Dayton (I never did decide which I liked better for the woofer and have been running left side sealed and right side ported this whole time...) I'll probably just keep building more and trying different drivers, maybe try some horns at some point. Just for fun.
Well, mentally a few weeks later, physically a while longer... I've still been around time to time but just reading. Kids, moved house/shop to new house & building new shop... have not had time for anything!
Finally got things set up in the basement at the new place and wow... I picked the worst room ever to use as a movie/listening room apparently, as the whole lower end of the frequency spectrum gets soaked up by crappy thin paneling on the walls and there seems to be a null spot right where you want to sit. Ugh. It sounds terrible, everything sounds terrible. Now I miss the sound I had in the previous house, which I didn't think was great, but...
The kids knock over or destroy anything I put in the living room with them, so I'm back to square one for a bit - rather not move my stuff up there for them to wreak havoc on.
For now, I may just go back and build a set of ported boxes for some A10.3s, or something similar and small to enjoy tucked away on a shelf somewhere else in the house. In the mean time, finish building my shop, fix a broken track miata, and then finally build the matching pairs to the Fane 12" and 18" Dayton (I never did decide which I liked better for the woofer and have been running left side sealed and right side ported this whole time...) I'll probably just keep building more and trying different drivers, maybe try some horns at some point. Just for fun.
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