There is an odd space in my music room. It measures 2ft wide, 2.5ft deep, and ~7ft tall. It is the yellow square in the top left corner in the attached drawing.
There doesn't seem to be a good use for that space. Then I started to wonder, if it is a good idea to frame it up into a subwoofer enclosure? I have a spare PA amp which could serve as the power source for the subwoofer.
I'm not sure where to start on the calculations. The online calculators I found all seem to start with a chosen driver, and then tune the volume and port size etc to maximize the output. I want to do the opposite: start with a fixed volume, and try to find the right driver (or drivers), and port size (if ported).
Any tip on where to start? Thanks!
There doesn't seem to be a good use for that space. Then I started to wonder, if it is a good idea to frame it up into a subwoofer enclosure? I have a spare PA amp which could serve as the power source for the subwoofer.
I'm not sure where to start on the calculations. The online calculators I found all seem to start with a chosen driver, and then tune the volume and port size etc to maximize the output. I want to do the opposite: start with a fixed volume, and try to find the right driver (or drivers), and port size (if ported).
Any tip on where to start? Thanks!
Attachments
~35 ft^3 in the corner is a good start on a [multi]driver sealed sub with preferably [4] or more drivers depending on size spread to create a floor-ceiling 'infinite' array. Since it's a full corner, vented normally isn't desirable unless it's in the form of a folded corner horn such as the big Klipsch and even it only goes down to ~35 Hz.
One potential problem is room width, speaker placement, so what are the room dims, speaker, seating locations and speaker performance specs? With the sub off in the corner, the distance to the far speaker may push the XO point really low. A much better layout would be to put the speakers along the walls with the seating lined up with the corner sub in the middle. This solves a lot of room interaction issues as a perk.
Anyway, got to nail down all these peripherals along with what this is for, power options, desired performance goals, any WAF, budget/whatever limitations before we can choose drivers.
GM
One potential problem is room width, speaker placement, so what are the room dims, speaker, seating locations and speaker performance specs? With the sub off in the corner, the distance to the far speaker may push the XO point really low. A much better layout would be to put the speakers along the walls with the seating lined up with the corner sub in the middle. This solves a lot of room interaction issues as a perk.
Anyway, got to nail down all these peripherals along with what this is for, power options, desired performance goals, any WAF, budget/whatever limitations before we can choose drivers.
GM
The main speakers are Kilpsch Corwall III; they have 102db sensitivity, and go down to 34hz. I mainly want to get a subwoofer for movies; not really a big fan of bass-heavy music. WAF is not an issue; this little corner space is tucked out of sight; a dark mesh grill will hide it well.
The room is rather long, at ~33ft; the front half is ~14ft wide; the rear half is ~25ft wide; the seat is ~12ft away from the front wall where the speakers are. Due to the presence of a fireplace, a couple of doors, 3 windows, the TV, and other things, the speakers need to stay where they are.
The spare PA amp is rated for 800 watts into 8ohm and 1100 watts into 4ohm. I figure that's probably enough power.
As for budget, I figure $500-$1000 in parts? None of the faces are showing, so I don't need the prettier grade of plywood; there is no need for sanding or finishing either. I have wood working tools, glue, nails, screws, etc.
Honestly I think it might be cheaper and easier to just buy a ready-made powered subwoofer. But I like to tinker
The room is rather long, at ~33ft; the front half is ~14ft wide; the rear half is ~25ft wide; the seat is ~12ft away from the front wall where the speakers are. Due to the presence of a fireplace, a couple of doors, 3 windows, the TV, and other things, the speakers need to stay where they are.
The spare PA amp is rated for 800 watts into 8ohm and 1100 watts into 4ohm. I figure that's probably enough power.
As for budget, I figure $500-$1000 in parts? None of the faces are showing, so I don't need the prettier grade of plywood; there is no need for sanding or finishing either. I have wood working tools, glue, nails, screws, etc.
Honestly I think it might be cheaper and easier to just buy a ready-made powered subwoofer. But I like to tinker
OK, thanks! Was hoping others would chime in, but......... anyway, a bit short on time ATM, though budget should be plenty and multiple sub drivers in a sealed array is the way to go since you have such efficient speakers. Room gain won't help much since the 1st mode is ~565/33 = ~17 Hz plus room expands, so will drop a bit due to 'slap echo' decay, especially if you can make the 25 ft wall a huge bass trap of sorts or at least very diffusive.
GM
GM
Honestly I think it might be cheaper and easier to just buy a ready-made powered subwoofer. But I like to tinker
Not necessarily based on performance/$$; four of these on paper are going to 'blow the doors off' anything you can buy OTC for $1k, not to mention the cool factor of having a corner full of huge sub woofers: Dayton Audio PA465S-8 18" Pro Subwoofer 4" VC 8 Ohm
They make so much SPL in a corner to ~match the Cornwalls that normally will be idling along in a sealed alignment, so plenty of dynamic headroom for EQing to 'taste': > ~110 dB/10 Hz/70 W, ramping up to > ~130 dB/25 - 175 Hz.
If you willing to accept a bit more distortion due to quadrupling the power to ~300 W, though still low enough for the preferred 6 dB crest factor, then you can still come fairly close to meeting the 115 dB/[1 m] Vs listening position THX reference [what most folks settle for] with just two.
Your main construction 'problem' is sufficiently bracing, sound damping the closet, baffle.
GM
In a house long ago, I had a very similar space which once was the front door and so it was framed in brick. I made a very heavy panel and installed 9 smallish subs, facing front and back. Luckily right near my satellites. Super bass.
With 35 cu feet, makes a nice sealed box. There is no useful analysis of sealed box enclosures since there is only one parameter: volume. The bigger the better.
I suppose the walls of your space are drywall. I wouldn't even sweat strengthening them since you'll prolly be benefitting from a nice compromise of sealed, IB, dipole, and leaky sealed. I bet that notion really appalls some people.
But is "PA" amp is code for distorted sound? Often is. Power requirements in this forum are often greatly exaggerated.
Be sure to come back to the forum with measurements of your results.
B.
With 35 cu feet, makes a nice sealed box. There is no useful analysis of sealed box enclosures since there is only one parameter: volume. The bigger the better.
I suppose the walls of your space are drywall. I wouldn't even sweat strengthening them since you'll prolly be benefitting from a nice compromise of sealed, IB, dipole, and leaky sealed. I bet that notion really appalls some people.
But is "PA" amp is code for distorted sound? Often is. Power requirements in this forum are often greatly exaggerated.
Be sure to come back to the forum with measurements of your results.
B.
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Thanks for all the suggestions and insight!
I'm going to start with building a much smaller sealed box with a single 18" woofer. See where it goes, then decides whether to turn that space into one killer subwoofer array, or a boring shelf, lol.
The PA amp is a Crown XLS 402; I don't know how much distortion it has; never had the opportunity to crank it up. Now I use an integrated tube amp to drive the Cornwalls, so the Crown is just sitting on a shelf doing nothing!
Re drywall: interestingly, one of the wall is cinder blocks, the opposing wall appears to be poured concrete covered by drywall; only the back wall is traditional framing.
I'm going to start with building a much smaller sealed box with a single 18" woofer. See where it goes, then decides whether to turn that space into one killer subwoofer array, or a boring shelf, lol.
The PA amp is a Crown XLS 402; I don't know how much distortion it has; never had the opportunity to crank it up. Now I use an integrated tube amp to drive the Cornwalls, so the Crown is just sitting on a shelf doing nothing!
Re drywall: interestingly, one of the wall is cinder blocks, the opposing wall appears to be poured concrete covered by drywall; only the back wall is traditional framing.
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