[Guest]

Hello,

I am looking to build a sub enclosure for my 5.1 surround setup I am doing in my living room. Basically I would like it to compliment my Infinity Primus setup so far but I only have about $400-$500 to do so. I was looking at the Shiva-X and a BASH 500 but I got to thinking... I have a few JL Audio 10w3 d4's laying around that I pulled from my truck a few years back. I had 3 of them on a Phoenix Power XS2500 (2ch amp w/ 500w RMS rating at 12v) and loved them immensely. I can always upgrade the sub later if need be but would like to start with something I have on hand if possible. I am used to building small sealed enclosures for car audio setups and especially what I called the 3/2 rule (where you put 3 subs in the same airspace you can build the enclosure for 2 and have proper airspace). It worked wonders on my 3 JL's. Although I would rather build a home theater sub with just one or two as I have a use for the other one in one of my MR2's that will finally be running again soon.

My main question is this... If I were to build an enclosure to fit one of the 10w3's in would it be better to go with a sealed or ported design given the use will be in the home now? Or should I just spend the few extra dollars and get the Shiva-X like I was planning before?

A little background info is this: My room is approx. 18x20 and has a vaulted ceiling that peaks about 10ft. I am trying to compliment my Infinity P362 fronts, PC250 center, and CS60 in-wall rears. We do about 90% tv/movies and about 10% music. If I left out any details that are needed to give an educated guesstimate please let me know.

Thanks in advance!

 

[Mike P.]

A pair of JL Audio 10w3 can be wired for a 4 ohm load, it just a question of seeing how they would model. I'm without modeling software until tomorrow when I get home.

 

[Guest]

I did run the numbers through WinISD and one, two, or three of them did not make much of a difference as far as I could tell. But then again I am not used to that program and probably have not found the intricacies of it. I am more of a bassbox guy but willing to learn. No rush on this as I am not even finished with putting my living room back together. We are installing bamboo floor and a custom built entertainment center.

 

[WmAx]

I would make a separate ported cabinet for each of the sub drivers. This will let you achieve far better bass response in the room, and consistently, with the subs placed strategically throughout. The driver you mention is a fair quality driver. I modeled these using the default data entry in WinIsd Pro for JL Audio 10W3-D4. Based on this, I would use each one for your purpose in a 2.5 net volume ported cabinet with a folded slot port of 3" high x 12" wide x 57" in length. The large cross section of the slot port is critical; it will allow for little to no compression or air turbulence in the lowest octave at and around the port tuning. Most ported cabinets actually have substantial port compression, resulting in substantially lowered output around port tuning. With this cabinet, you will have a very smooth and dampened response, with -3dB at roughl 22Hz. You should use a subsonic filter set at abot 20-22Hz to ensure your driver does not unload and have excursion issues under the port tuning. With three of these placed around the room in the specified cabinet, you should be able to achieve well past reference SPLs with no audible distortion or noise(s). You would not likely ever need to 'upgrade', if you used all three of these as specified, unless you just wanted to for lower extension, say for example, response to 15Hz or something like that.

-Chris

 

[Mike P.]

The JL Audio 10w3 models pretty good for a 10 inch in a ported application. In a 3 cu.ft. box with a tuning of 23 hz, porting is kept simple by using one 4 inch flared port full length, which is 18 inches. Air speed is acceptable at a maximum of 27 m/s with 250 watt input power. Building a pair of these would allow 2 of the subs to run off a 500 watt plate amp at a 4 ohm load. A sub sonic filter would be required at 20 hz with this setup. Below is the SPL graph of a 10w3 with 250 watts and a Shiva-X with 500 watts in the recommended 6.6 cu.ft. tuned to 18 hz.

 

[WmAx]

The JL Audio 10w3 models pretty good for a 10 inch in a ported application. In a 3 cu.ft. box with a tuning of 23 hz, porting is kept simple by using one 4 inch flared port full length, which is 18 inches. Air speed is acceptable at a maximum of 27 m/s with 250 watt input power. Building a pair of these would allow 2 of the subs to run off a 500 watt plate amp at a 4 ohm load. A sub sonic filter would be required at 20 hz with this setup. Below is the SPL graph of a 10w3 with 250 watts and a Shiva-X with 500 watts in the recommended 6.6 cu.ft. tuned to 18 hz.

View attachment 11022

Why use the small 4" port, when a slot port is easily made and in this case can provide for zero port turbulence or compression?

-Chris

 

[Mike P.]

Simply for ease of building. Mounting a full length 4 inch flared port is about as easy as it gets. With a maximum air speed of 27 m/s port turbulence or compression is a non issue in my opinion.

 

[Guest]

Thank you all for the input. I will definatley be going the DIY route now as I had to spend quite a pretty penny on some glue for my bamboo flooring last night. I was looking last night and I really only have enough space to put one sub though. I won't have room for 2 or 3 without the wife going over to the dark side and questioning everything I am doing . I may can swing a Shiva-X and bash 500 though. I just need to look in my finances and see. But I like the way just one Shiva-X models compared to the JL's.

 

[Mike P.]

If the Bash 500 you are considering is from Parts Express, be aware that the factory default for the subsonic filter is around 30 hz. ( which makes absolutely no sense ) You'll have to change 2 resistors to lower the SSF.

 

[Guest]

Thanks for the input. I was looking at this in WinISD and it looks like a single 10w3 d4 with something like a BASH 300 will do decent. I have to stay within my budget constraints and space limitations. Otherwise I would buy 2 of the nice SVS setups! So using what I have on hand I can just purchase a BASH 300 and I have a half sheet of 3/4" MDF to get me started with, just need to buy the port also. Would this port do the trick?: http://www.parts-express.com/pe/showdetl.cfm?Partnumber=268-352

Just don't want to get the wrong stuff. Maybe later I can upgrade to something with more punch. But going from the speakers in my 42" LCD TV to this is already light years different.

Any suggestions on a box design? Downfire, front fire, driver down/port front, etc?

 

[Mike P.]

That's the right port that you linked to. Make the cabinet so it has an internal volume of 3.3 cu.ft. That will give a net volume of 3 cu.ft. after the sub, bracing and port volumes are deducted. Sub orientation is up to you, down firing does offer some protection over front firing.