hometheater/game room subwoofer

[mwerling1212 1]

I am wanting to build a new sub for my room. It will consist of a Soundsplinter RL-P 18 on a 500 watt Oaudio plate amp. I have the 18 already, but i still need to buy the plate amp.

My question is about the enclosure and placement of the enclosure. The box specs on the Soundsplinter website say 12.8 cubes tuned to 18hz. I want to put the sub under my desk, but im not sure were to put the sub /port. ill try and post a picture of the desk and were it is compared to the rest of my system.

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theres the desk i want to put it under

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theres the desk to the left, and my couch to the right. then directly to the right is were my tv/reciever and towers are.

The max dimensions under the desk is length=54 height=25.25 depth=22.5. I plugged some numbers into winisd but im not sure what all the graphs mean.

Thanks for the help!

Edited November 19, 2009 by mwerling1212

[patented17 21]

In my apartment, I got my Evo sub in the back right corner of the room. In a 4.0cu^ft @ 25hz, it seems to workout fine, but our living room is almost a perfect square. You can always just make the box and try different placements.

[mwerling1212 1]

Well i wanted to put it behind my couch, but the box will be way to big. Its pretty much either under the desk and thats it. my room is very small.

[patented17 21]

Well if it fits, then try it. I was just thinking if you were to use the desk, it would be kind of hard.

[mwerling1212 1]

It should be alright in there. i put a little ten in there to see were the nulls and sweet spots were, and it sounded ok from were i sit. I still dont know were i should put the sub and port, and how much port area i should use though.

[slim2fattycake 85]

How big is the room? I think that with it being place against a wall, you will get more bass output. If you have a smaller built sub and box try putting it under the table and switch directions and then getting an spl meter (radio shack meter, that is all you need for this and it is about 20 dollars I think) if you want more output for the power. Test and see with the meter at your sitting area which orientation is the loudest. Also, what game system, media device, peripheral devices, etc? Comeon details man. lol. That sub and that tuning with that size box is going to be beast especially if that room is as small as I think it looks like.

O and I checked your numbers under the table and it looks like you have about 17 cubes to work with before sub, port, and bracing displacement. info on your port size?

[mwerling1212 1]

Sorry i forgot some of the details! lol. My room is 13ft by 11ft. I have a Harman Kardon AVR 247 that will be here tomorrow, polk monitor 50 floorstanders, CS1 center, and R15 rears. My gaming system is a ps3. I modeled a box on the re audio box calculator with a 3 by 23.5in. port with is about 70 sq in. of port. the length of the port is 34 inches. I heard that the re calculator isnt accurate, but thats the only one i know how to use. Is 70 sq in. enough?

[slim2fattycake 85]

I guess you will be watching blueray too right? I don't know if its a user error or not but this doesn't sound good, http://reviews.cnet.com/av-receivers/harman-kardon-avr-247/4864-6466_7-32445662-1.html?ord=creationDate+desc&tag=txt;uo

[mwerling1212 1]

oooo man! i didnt see that one! i thought i did my research! lol. but i think ill just use my hdmi for video only and plug it from my ps3 directly into my tv, and use an optical cable i have for audio. Im not too concerned about having supreme HD though. My Tv is only a 720p Emerson and i wont be upgrading for awhile.

[KU40 173]

I would probably downfire the sub and port. IMO, box positioned in a corner is ideal, but against any wall is next best (front wall with the TV is best, then side walls, and back well least favorite).

[///M5 2,833]

I'd probably build a coffee table, but only since it will be hard to do much else. A sonotube in the corner would be fine as well.

[topgun 262]

Remember that if you do build a coffee table for a speaker box that it needs to be braced to hell to prevent unwanted vibrations.

[///M5 2,833]

True, but that sub deserves a braced like hell box.

[topgun 262]

True, but that sub deserves a braced like hell box.

Agreed. I don't think most people realized the amount of bracing needed to not feel vibrations when you put your feet on it though... Maybe they do but don't want to put that kind of time into the build though.

[mwerling1212 1]

I cant do a sonotube or a table, my room is just not big enough. I orginally wanted to build a sonotube but the tubes diameter is too large to put any were without its being in the way. is there any problems with it being under the desk firing out along with the port? I cant downfire it either because i dont have enough airspace for it. I can get around 13-13.5 cubes excluding bracing and woofer displacment. Would it really make a difference if it is a little less than 12.8 cubes? Im going to window brace it. If it being too small is a problem, would adding stuffing or pillows help?

[///M5 2,833]

You are going to need a couple cubic feet for bracing if you want to do this right.

[KU40 173]

I cant do a sonotube or a table, my room is just not big enough. I orginally wanted to build a sonotube but the tubes diameter is too large to put any were without its being in the way. is there any problems with it being under the desk firing out along with the port? I cant downfire it either because i dont have enough airspace for it. I can get around 13-13.5 cubes excluding bracing and woofer displacment. Would it really make a difference if it is a little less than 12.8 cubes? Im going to window brace it. If it being too small is a problem, would adding stuffing or pillows help?

I don't understand how airspace fits into not being able to downfire it? Or is your concern with the room needed under the box between it and the floor if downfiring?

[satwilson 1]

I cant do a sonotube or a table, my room is just not big enough. I orginally wanted to build a sonotube but the tubes diameter is too large to put any were without its being in the way. is there any problems with it being under the desk firing out along with the port? I cant downfire it either because i dont have enough airspace for it. I can get around 13-13.5 cubes excluding bracing and woofer displacment. Would it really make a difference if it is a little less than 12.8 cubes? Im going to window brace it. If it being too small is a problem, would adding stuffing or pillows help?

I don't understand how airspace fits into not being able to downfire it? Or is your concern with the room needed under the box between it and the floor if downfiring?

You guys are all nuts, in a room that size a ported 18" woofer will be way overkill, and the size of the enclosure impossible to use. Put that speaker in a sealed enclosure and hope it doesn't overpower/rattle/buzz that small room to death. I am assuming you will use a plate amp that has the power that driver needs. A sealed enclosure will be alot smaller. OldSchoolSQ

[slim2fattycake 85]

Well 1, he is using a 500 watt amp which is half the power handling of that sub, and 2, its called a gain knob. You don't have to have it up much. A more efficient box allows him to be able to turn it up when he wants or turn it down.

[satwilson 1]

Well 1, he is using a 500 watt amp which is half the power handling of that sub, and 2, its called a gain knob. You don't have to have it up much. A more efficient box allows him to be able to turn it up when he wants or turn it down.

3) I have 2 12" SSDs in a sealed box in a 12x15 room and can't run them at full power without rattling everything in the room, the floor in the second story, stuff in the adjoining room, etc. I assume an 18" in a ported box, in a smaller room..............more than he needs? And he is having trouble finding room for a ported box................why drive yourself crazy finding room for a larger more efficient box that won't fit in your room and you don't need the added efficiency hmmmmmm? Edited November 21, 2009 by OldSchoolSQ

[mwerling1212 1]

to ku40, the top of the desk is the limit for my height of the box, so if i made it down firing, i would need to subtract some for the space needed under the driver, making the box smaller.

to m5, would pillows or stuffing help since the bracing will take up a couple cubes?

to oldschool, I know it is a little overkill but i already have the woofer from my car, and thought that i could get a 12.8 cube box under my desk. I might consider a sealed box, but if i can build a ported box it would be that much better.

thanks for all of the input guys.

Edited November 21, 2009 by mwerling1212

[KU40 173]

I would say just try building a ported box as large as you can, even if it doesn't get up to the recommended 12.8 cubes. You still may like the sound of it. Plus if you don't, it should be easy to just chop the box in half and make it sealed.

[mwerling1212 1]

good idea ku. Thats what i will do. thanks

[///M5 2,833]

Don't compromise on the space. If you have to, buy a 15" instead.

[KU40 173]

Don't compromise on the space. If you have to, buy a 15" instead.

Or do that. That thought slipped my mind.