Need opinions on SP4 15 enclosure plans

[Shake'n'Bake 0]

So, I'm waiting on my loaded dual 2-ohm SP4 15" driver. I've been paying around with designs using Torres box calculator and Winisd and I'm hoping I've got something usable.

 

After playing with a mock-up box (reinforced poster-board + hot glue did the trick), I figured out that the biggest size I can fit comes up to kinda disappointing dimensions:

 

Outer dimensions - 16" tall X 26.75" wide X 23" deep

Inner port dimensions - 14.75" X 3", 27.5" long for an estimated tuning of 32hz after driver/Plexiglas (details later)/bracing displacement

Net volume comes up to a whopping  3.42 cubic feet, with 44.25 square inches of port. 

This is with all 3/4" MDF as well as an extra layer to the baffle.

 

I'll be running the driver on my Rockford T1500.1BDCP, rated at 1,925 watts RMS at 14.4 volts. Electrical-wise, my system held very steadily at 14 volts or so (measured at the front battery) during metering with termlab on another driver (RE SXX 15d2). I've done the big-3 wiring upgrade, have 1/0 lines running from my front stock battery to a XS Power D1200 in the trunk, I'm just lacking a new alternator, which isn't readily available for my car. I do hope to eventually upgrade to a more powerful amp + add batteries to support it at a much later date.

 

I will be listening to mostly dubstep, Decaf songs, and a bit of music by Bassnectar and similar artists. I want this setup to be fairly musical, and I don't plan on competing, but I still want it to SLAM on the lows. I originally wanted 30hz tuning, but I don't think space will allow, unless this driver can perform nearly as well in 3 cubes as it can at 3.5...

 

Aesthetically, I plan on doing a lot more than the last box I made (big dual 12" with Line-X coating). I think I'm going with black auto-carpet wrapped all around, I'm going to spray the interior with black Plasti-dip to cover up silicone/sealants and give extra air/water-tightness + for looks. I plan on having a 10" tall X 13" wide X 1/2" thick Plexiglas  window centered with the driver and facing into the car, complete with two multi-color LED strips spanning the top and bottom of the window to light it and the driver. LED system, complete with 2 wireless key-chain remotes will arrive in time for the build too!

 

 

My biggest concerns: will this baby perform well in this size box? And will it have enough port area?

I appreciate any thoughts and advice!

 

Screen cap of Torres Tuning Calc: http://s21.postimg.org/f8ejkyks7/SP415_Enclosure.png

Screen cap of WinISD: http://s12.postimg.org/r7xmnrckt/SP432hz.png

 

This will be going in the trunk of a 2012 Honda Civic coupe btw.

Edited December 12, 2013 by Shake'n'Bake

[EPerez 236]

It can be put in, but I wouldn't. It is definitely not optimal. Is it possible to switch your order to a 12"?? How long ago did you order. This is why it's best to measure first then buy the sub(s) that fit the space.

[Shake'n'Bake 0]

It can be put in, but I wouldn't. It is definitely not optimal. Is it possible to switch your order to a 12"?? How long ago did you order. This is why it's best to measure first then buy the sub(s) that fit the space.

It's been 15 days since my order, but I'd rather try and work with a 15" than lose the cone area. The recommended ported enclosure size on the Fi website is 3-5 cubic feet, so I figured that I would still get more out of it than the smaller box (smaller than this design) I was running my 15" RE SXX in. If my trunk opening was just a little wider I could do much better...

[EPerez 236]

A smaller sub in an optimal box is almost always better than a larger sub crammed into a small not well designed box. I'd take the smaller sub anyway over the larger sub in that situation.

 

Box size is on the small side, not bad, but the bad part is the lack of port area.

 

Try taking off the rubber surround that goes around the trunk. Also take off the molding around the trunk opening. I actually got inches from doing this.

[Shake'n'Bake 0]

A smaller sub in an optimal box is almost always better than a larger sub crammed into a small not well designed box. I'd take the smaller sub anyway over the larger sub in that situation.

 

Box size is on the small side, not bad, but the bad part is the lack of port area.

 

Try taking off the rubber surround that goes around the trunk. Also take off the molding around the trunk opening. I actually got inches from doing this.

As far as port area goes, what would you say the optimum amount would be for this particular driver? If tuning a little higher and increasing the width of the port would help a lot then I would consider doing so, just so it could still safely handle mid-to-upper 20's range.

And I already pulled out the rubber seal and molding from the opening, Honda really hates bassheads apparently, cause it didn't do much... 

[EPerez 236]

I would say a minimum of 60in2 of port area with 70-80in2 of port area being where we would like it.

[swift 501]

If its built right you should be fine with that enclosure. Not perfect but it should sound just fine. I have my 15in FI Q in a 3.6cu box with 43 sqin of port and it slams and sounds great. A SP4 sounded killer in my box when I tried my friends.

 

My single 3yr old Q on a BC2000 does a 147@ 40hz and still does a 140 @25hz. And I bet money it would be even louder with a SP4 in it. Different vehicle but still.

[Shake'n'Bake 0]

I would say a minimum of 60in2 of port area with 70-80in2 of port area being where we would like it.

 

I'm re-working the numbers a bit, and I might just drop the enclosure in without the sides, then slap them on to gain another 1.5" in width. I'm really not sure how fun wrapping the thing with auto carpet would be while in the trunk though... lol!

 

If its built right you should be fine with that enclosure. Not perfect but it should sound just fine. I have my 15in FI Q in a 3.6cu box with 43 sqin of port and it slams and sounds great. A SP4 sounded killer in my box when I tried my friends.

 

My single 3yr old Q on a BC2000 does a 147@ 40hz and still does a 140 @25hz. And I bet money it would be even louder with a SP4 in it. Different vehicle but still.

 

Comforting to hear for sure! What was your enclosure tuned at?

 

I may just stick with my current design since my trunk isn't the best for volume, and I don't know that I could pull off carpeting it inside the trunk... If I can manage to have it sound awesome and just be missing perfection by a little bit then I'll be happy, and I'll just plan on my next vehicle having a better trunk... Even if it merely crushes my RE SXX performance I'll be pleased, because it was already pretty fun. 

[swift 501]

Mine is tuned at 29hz.

I forgot to mention that I also built a enclosure for a Altima my friend has, it's 3.3cu tuned at 33hz and he is running a SP4 on 1200watts and it sounds incredible. It has around 45sqin of port.

Edited December 12, 2013 by swift

[Shake'n'Bake 0]

Mine is tuned at 29hz.

I forgot to mention that I also built a enclosure for a Altima my friend has, it's 3.3cu tuned at 33hz and he is running a SP4 on 1200watts and it sounds incredible. It has around 45sqin of port.

Hmm... Well I'm not so worried about it performing then. lol

Just leaving room for improvement down the road! Haha

[swift 501]

It was built for a Q and once he upgraded to the SP4 it sounded good enough no rebuild was necessary

[swift 501]

This is his setup I did

[Shake'n'Bake 0]

This is his setup I did

 

 Nice and clean! Can't wait till Sunday when I can build mine! Though I probably won't have my SP4 till the 22nd...