This is a project I've wanting to tackle for some time. I now have a pretty decent room to set up a nice little theatre that would require a riser for the rear seating. So why not a pair of subs in the riser?!
The gear and projector will be at the closet end and the 2 mirrored 58"X60" horns will be in front of the gear. This end of the room is earth/rock filled, this is why the walls are thicker. The sub's internal baffles will 11" high giving me an overall riser height of about 12.5". I want to make it in two sections for portability, I expect to move in a few years.
Why not 60"X60" boxes? the room is about 2.5 inches shy of 10 feet wide and besides, I've learned not to trust the squareness and flatness of typical construction! A bit of trim will fix the gaps.
I have a preliminary sketch attached, also specs for the drivers I would like to use. I have a HSU sub plate amp and I expect to run the 8 ohm drivers in parallel.
The cone area would seem to dictate a throat size of 5"X11" .
From here my plans get more sketchy, I'm thinking these drivers would work fine in the approximate 9 cubic foot volume sketched. The horn length is about 12 feet (very approximate) a length, I recall reading somewhere, that would allow bass to extend to around 25 hz.
Well that's my crazy loosey goosey plans so far. 🙂hypno2:^
)
Clearly I need help and would welcome input and ideas from you Horn Experts!
Thanks!!!
The gear and projector will be at the closet end and the 2 mirrored 58"X60" horns will be in front of the gear. This end of the room is earth/rock filled, this is why the walls are thicker. The sub's internal baffles will 11" high giving me an overall riser height of about 12.5". I want to make it in two sections for portability, I expect to move in a few years.
Why not 60"X60" boxes? the room is about 2.5 inches shy of 10 feet wide and besides, I've learned not to trust the squareness and flatness of typical construction! A bit of trim will fix the gaps.
I have a preliminary sketch attached, also specs for the drivers I would like to use. I have a HSU sub plate amp and I expect to run the 8 ohm drivers in parallel.
The cone area would seem to dictate a throat size of 5"X11" .
From here my plans get more sketchy, I'm thinking these drivers would work fine in the approximate 9 cubic foot volume sketched. The horn length is about 12 feet (very approximate) a length, I recall reading somewhere, that would allow bass to extend to around 25 hz.
Well that's my crazy loosey goosey plans so far. 🙂hypno2:^
) Clearly I need help and would welcome input and ideas from you Horn Experts!
Thanks!!!
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I am not sure why you want the complexity of a horn in such a small space, as you are already considering expensive drivers you could achieve the same SPL using sealed enclosures and more power without the low frequency cutoff limitation! please correct me if i am wrong ?
I have to make a riser anyway and thought I may as well try a project that's interested me for a while. There is a volume of almost 600 cubic litres available per sub, which I think should provide some creative options. I'm totally open to thoughts on my scheme and alternate ideas. I don't need this sub's range to reach higher than 70 hz either.
Grok,
Sounds like you have room for a variation of the "Kraken" tapped horn which uses 2 12" jbl car woofers. Also give a look at Tom Danleys "Spud" tapped horn design. Both are tried and true designs. Good luck.
Sounds like you have room for a variation of the "Kraken" tapped horn which uses 2 12" jbl car woofers. Also give a look at Tom Danleys "Spud" tapped horn design. Both are tried and true designs. Good luck.
Sorry I was talking about the low frequency cutoff of the horn. Sounds like you love woodwork, go for it 🙂 BTW I have one of those JBL car woofers with an Xmax 15mm and wow does it wack out the SPL below 30hZ in a big sealed box, so two horn loaded with a long horn would be real impressive, make sure the rear chamber is big enough to get them up to xmax though or you loose the advantage (mine is ~50Litres for 1 driver).
John
No worries John.
In my simplistic mind, I'm thinking sub with horn amplification. 😀
After a lot of wading through the threads the "Kraken" design does seem to hold some promise.
I would really like to utilise as much of the of the cubic footage as I can, I believe it holds some serious potential for a sub.
Hi Mark, thanks for chiming in. I am considering all ideas. I want to maximize the usage of the riser space, any sketched ideas are welcome. I think many people could use a sub/riser for home theatre use. Particularly one that is moveable from house to house.
The TH-SPUD is designed as a low profile subwoofer riser. Plenty of information is available to DIY one that is very similar.
Danley's is 11 x 48 x 45 but it wouldn't be terribly difficult to make one bigger if your size requirements are fixed. You could achieve even more gain with a bigger box.
This is what the internals look like.
Danley's is 11 x 48 x 45 but it wouldn't be terribly difficult to make one bigger if your size requirements are fixed. You could achieve even more gain with a bigger box.
This is what the internals look like.
The TH-SPUD is designed as a low profile subwoofer riser. Plenty of information is available to DIY one that is very similar.
Danley's is 11 x 48 x 45 but it wouldn't be terribly difficult to make one bigger if your size requirements are fixed. You could achieve even more gain with a bigger box.
This is what the internals look like.
Very Cool! a couple of those could support a Sofa!
Yep, it was actually conceived as a couch riser sub from whence the 'couch potato' = SPUD was born: CouchSubHatchPanelConcept_0001.jpg Photo by mynym | Photobucket
Later, they enlarged it to use dual 12" with a ~11 Hz low corner and offered as a kit for awhile: Danley DTS-10 "Super Spud" DIY kit - AVS Forum | Home Theater Discussions And Reviews
GM
Some good ideas!
I can't imagine why anyone would go to the trouble of making a riser for their home theatre and NOT build a sub into it!😀
I can't imagine why anyone would go to the trouble of making a riser for their home theatre and NOT build a sub into it!😀
Hmm, for HT, 80 Hz is the norm and since THs are typically [2] octave alignments, then ~20 Hz is the lower limit unless you use fairly expensive drivers that will allow ~14 Hz/[2.5] octaves.
A FLH OTOH is only limited by its path-length, driver specs and total net volume [Vb], so you can either go low [and for HT this means < 10 Hz nowadays] or higher cut-off and louder.
The room's gain will begin around 35 Hz, so only needs a mouth big enough to support this low in half [2pi] space [~5972"^2], but can be tuned much lower. With only an 11" high x 16 ft/192" width mouth though [~2112"^2], ~59 Hz is it, so not doable without significant EQ even if you manage to get some quarter [1pi] space loading too and of course since it will be up front, room modes will chop up its response pretty bad.
Mark Kravchenko has done at least one way more undersized FLH than I have [its simmed response looks like a variable frequency warble tone 😉], so maybe he will elaborate on what all it takes to make it perform well in the allotted space.
Still, all things considered, [multiple] driver IB [sealed] seems the way to go to get both high SQ and the very low usable corner frequency required for more n' more movies and make some smaller subs to place around the room to help smooth out the room's response, including at least one up a side wall to deal with the vertical room modes that's not considered in this otherwise excellent research: http://www.harman.com/EN-US/OurCompany/Innovation/Documents/White Papers/multsubs.pdf
GM
...........or fake front stages; all that work just for looks, what a waste! Then there's all those beautiful columns along the walls that could be subs or at least multiple surrounds.
GM
I see my name being used in vain once again!
Hey there Greg.
Yes I have built quite a few undersized subs. But the warble tone that they sim out to is not that offensive in the real world use.
The fact being that every driver in a practical space has the same warbling output when at your listening position.
The kick in the pants situation when designing a riser is the desired height limits.
I haven't done a design for that because it is so individual to the location.
But if I had a buck for every time I was asked I's be able to buy a decent burger meal.
Mmmm. Burger. ( Lunch time )
I might make a universal type 4 x 4 design that could work. Standard maximum step height is 7 inches or 178 mm. That could be used as a basis to design something that could be used in many applications.
And I have an 8 inch driver that is almost ready for the big bad world that would be just the ticket. Hmmm more thinking required here.
Hey there Greg.
Yes I have built quite a few undersized subs. But the warble tone that they sim out to is not that offensive in the real world use.
The fact being that every driver in a practical space has the same warbling output when at your listening position.
The kick in the pants situation when designing a riser is the desired height limits.
I haven't done a design for that because it is so individual to the location.
But if I had a buck for every time I was asked I's be able to buy a decent burger meal.
Mmmm. Burger. ( Lunch time )
I might make a universal type 4 x 4 design that could work. Standard maximum step height is 7 inches or 178 mm. That could be used as a basis to design something that could be used in many applications.
And I have an 8 inch driver that is almost ready for the big bad world that would be just the ticket. Hmmm more thinking required here.
7 inches? I think closer to 10 or 11 inches, screen height makes a difference.
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