Sub Firing into Rear Seat

[Threehz]

Ok so when I was originally thinking of doing my sub setup I was thinking IB setup, and sticking to that plan with a setup close to bmwman91's...

My rear seat has no fold down center for the ski-pass, so looking inside my trunk, there is the rectangle cutout in the metal for the skipass and then just the foam backing of my rear seats. I'm building a box that will surround that skipass and have my woofer firing straight into it.

Originally this worried me as a woofer or any speaker works by moving air, if it is firing into a wall then it will not be very effective correct? However bmwman91 said that there was no change in sound with ski-pass open or closed and I thought the Lukebox works the exact same way firing into the ski-pass so I assured myself if it is working for all these people, it works.

However I'm still unsure about it.. Can anyone with a setup similar to this tell me how it works out, or can anyone clue me in as to why I'd be wrong to say firing into the back of the seats will be highly ineffective?

Thanks!

[AndrewBird]

Luke box's are built this way, but he also ports into the cabin. He has said that the foam does affect performance, but not by a lot.

I built a box for my Jetta that basically replicates a Luke box and I can hardly tell the difference between having he seat there and not having it there. Bass for me is felt more then heard.

[nrubenstein]

Past a certain volume level, the seat will start making a ton of noise.

[Threehz]

Yes, in fact past a certain volume the woofer will not see any gains because it will be pushing as much air as it can, and will be negatively affecting SQ and possibly hurting the woofer itself...

My "box" is approximately 1.76cuft with a 15" woofer firing into it, now I'm sure there is a way to calculate how much air my woofer will move at "max" volume by using the speaker specs such as Vas.

[nrubenstein]

Yes, in fact past a certain volume the woofer will not see any gains because it will be pushing as much air as it can, and will be negatively affecting SQ and possibly hurting the woofer itself...

My "box" is approximately 1.76cuft with a 15" woofer firing into it, now I'm sure there is a way to calculate how much air my woofer will move at "max" volume by using the speaker specs such as Vas.

A 10" woofer in a Luke box will cause the seat tomake a shit ton of noise at about 30% volume. I certainly wouldn't waste the effort on a 15 unless you are going to suck it up and get a ski pass seat. Or a cloth seat.

[poopin04]

I just bought two 3inch speaker cones from ebay and ported my back seats. I have the vinyl back seat so I didn't mind cutting it, as they're dime a dozen. Since I did this I can honestly say I feel and hear the bass better. If my box was ported I'd imagine it feeling better though.

[Threehz]

A few people on DIYMA have said that it should work fine, I guess it's really just all guessing game until it's done.

After finals next week I'll actually have time to finish it up and test things out.

I figure if it doesn't sound right I'll port the box that's being fired into, up into and out the rear deck. That'll be quite a mess of tuning but may just work out. Worst case is I buy 2 new pieces of MDF and seal the inner 4th of the trunk off kind of like the original plan hmm.

Thanks for all the input guys.

[Wh33lhop]

A 10" woofer in a Luke box will cause the seat tomake a shit ton of noise at about 30% volume. I certainly wouldn't waste the effort on a 15 unless you are going to suck it up and get a ski pass seat. Or a cloth seat.

I haven't experienced this. I've noticed if my seat belt buckles are in their little slots in the seat they will make noise, but the seat itself does not. I have no armrest and no foam cut out, and I play LOUD fairly often.

[AndrewBird]

I bet seat material has a lot to do with it. Leather/vinyl would block a lot more sound then cloth would I bet.

[StereoInstaller1]

Dude, why not get a spare iS rear seat and hack it up? Make a tunnel of MDF, wrap it in vinyl...do something cool and unique, dream it up yourself. You can always port the seat with a pair of 4" ports, that makes a HUGE difference.

[Threehz]

Moneyy...

I already had everything to do my current setup, and audio is at the very bottom of my priority list right now sad as it makes me. Once the holidays are over then I may very well pick up an extra rear seat as they seem to be pretty damn available.

Just wondering how I should best use what I've got :)

[devon.818]

dont reinvent the wheel, listen to luke

[LJ851]

dont reinvent the wheel, listen to luke

Seriously, the man has been around the E30 block a time or two.

[dkbmxer002]

i have a cv4 4 ohm 10 with a kicker dx500 amp in a sealed and stuffed box and it sounds PLENTY loud imo. mine is in a cheap piece of shit box facing the tail lights.

[Jalves619]

I have a black armrest rear seat in Tucson that needs a new home. I'm in Flagstaff at the moment, but I should be coming down after finals week. I also have an extra cloth seat in Flagstaff if you want to try modifying one. Shoot me a PM if you're interested in either.