[dynamowhum]

I have done a quick search and have not found this idea posted. Is it possible to make a seating platform for my couch into a subwoofer? If I where to make a platform 4'X8'X1' that would roughly be 32 ft^3- bracing and porting. Would this work or is it to shallow? I could bump the area under the couch another 4" or so if that would help. I am starting to think this would be do able that way. Talk about a real whoopee cushion.

 

[Mike P.]

" ScruffyHT" was talking about it with 4 CSS SD12 subs. His thread is here:

http://www.hometheatershack.com/forums/diy-subwoofers-sealed-ported/17922-opinions-needed.html

Driver size will determine the height of the riser if front or rear firing. There's the option of up firing but driver protection becomes an issue. Do you have a sub driver in mind?

 

[dynamowhum]

Yes I was going up firing. I was planning on doing the Fi 18Q. I did a cost breakdown on this last night and decided not to do it. I guess I will just put another IB in the back of the theater to go along with the one I have upfront. Sorry to have taken your time.

 

[Mike P.]

Not a problem. What are you powering the Q18's with?

 

[dynamowhum]

The old standard ep2500

 

[SteveCallas]

I really don't think you should go up firing with a Q18 and only 12" of height on this riser. You're going to have only a couple inches clearance underneath the driver - all the rear waves are going to reflect off the floor at nearly full intensity. Litle clearance also means that the warm air coming out of the driver vent can build up, and since warm air rises, with an up firing driver, heat disspation isn't going to be very good.

Multiple 12" drivers mounted front firing sound like the better approach.

 

[mayhem13]

That sounds like a folded horn with Peerless XLS 10" drivers to me.....One hellof a riser!

I have 4 10" surplus NHT subs with a low fs (21.5) that have 12.5mm excursion and love big boxes. Here's a sim ported and tuned to 17hz in 23 cuft....not bad for 4 10's with 100w each eh?

I was running these in pairs in 5.5cuft each tuned to 21hz in endtables until my neighbors came knocking and really pissed me off. They've since been replaced with dual 18's sealed. Here's one of the table subs before replacement.

The drivers are available and in like new condition if you're interested.