new guy here with a Chevy Cruze

[Gnfanatic1 0]

Hey guys, I am looking for ideas/knowledge on setting a IB setup in my cruze. I have not purchased any subs yet. I do not want a box, do not want to break windows. Just want a nice solid punch. I am thinking going to a IB setup so I still have my trunk but not sure where to go for this. Against the seat's or maybe rear deck? Any idea's? Any of you guys have worked on a cruze? I have a zed audio 600 watt mono I would like to use to save money on this build. The rear deck had to empty holes in it (6x9) Not sure if I have room to enlarge the holes to put 8's. Need to measure.

 

thanks!

[daviddto 90]

_{Welcome to SSA !  I will let the guys with more knowledge answer your questions.}

[Sencheezy 689]

[S.DeYoung 967]

You will want more cone area than two 8s for IB. Install a baffle behind the rear seats that fold down. I would try to use the biggest woofers that can physically fit.

[nem 2,019]

Welcome

[jcarter1885 995]

[altoncustomtech 773]

to the forum!

 

I have no experience with the Cruze's but I do have some experience with what you're looking to do.  As Sean (W140) mentioned you'll really want larger drivers (i.e. more cone area) when doing a setup like that.  I just happen to have recently done something very similar with a pair of 8" Dayton woofers in my Olds 88.  While the output is quite fair considering the drivers and power being used many people will find it lacking.  If you're truly not after a ton of output nothing smaller than 10's and 12's would be be the best route to go.  While something bigger like 15's would be best for output, that car is small enough that fitting them side by side behind the back seat might prove to be a problem.  

 

The most important things to remember if you want to do an IB setup is having a solid structure and sealing.  With an IB setup everything, and I mean everything where the subs mount and around that point will need to be braced up so that it's solid.  When the speaker cone moves the motor structure and frame try to move the opposite direction.  It's Newton's third law of motion, "For every action there's an equal and opposite reaction."  If the structure the speaker is mounted to moves then some of the force that should have been transferred to the cone is lost which results in a loss of output, rattles, non-linear response, and all sorts of things that are unwanted in audio.  The larger and more powerful the speaker the stronger that structure needs to be, there's more force involved.  Without an enclosure what the speaker mounts to and everything around is subject to movement and lets face it with today's cars there's just not a lot of really solid structure in the first place anymore.  The more you do to make it strong and unmovable the better off you'll be.  The second point is with sealing the back wave of the speaker from the front one.  When you play a speaker free air you can't hardly hear it (especially lower frequencies) because the sound wave from the front of the speaker and the sound wave from the back of the speaker are opposites.  When they meet they cancel out and you don't hear much.  Without an enclosure in an IB environment it's paramount to have every hole where any sound waves can leak from the trunk, or behind the drivers, sealed so that it can't reach the front side.  Sound deadening and sealing with many different kinds of materials will be absolutely necessary to prevent as much of this as possible.

[Randal Johnson 544]

Welcome. My wife has a Chevy Cruze.

[Gnfanatic1 0]

Thanks guys, I appreciate the help. If I am going to mount it right behind the seats I would perfer a single sub setup (15in) . right in the middle , behind the seats. I have a 600 watt zed audio amp I have the option of using as well. I believe I understand wehat you mean when it comes to reinforcing. I suppose 1.5 inch thick plywood with some additional bracing would be suffice to hold this sub?? Which model SSA SUB should I be looking at for this job? 600 watts, nothing exotic. I will close the 6x9 holes in rear deck with non-cut baffles and use something like dynamatt on the entire rear deck, trunk floor and inner fenders. Anything else??

[altoncustomtech 773]

Sounds like you pretty well have it figured out to me.  Everything you mentioned is correct and necessary to make a go of using an IB sub setup.  Don't skip over the small holes though.  Covering the big ones like the 6x9 holes is definitely very important but even the small ones will degrade performance if they're not covered as well.  If you were really wanting an SSA sub I think the closest one to fit the bill for you is the GCON.  Fi has a line called the IB3's that are purposely built for IB use and they come in a 15" size.  

[Gnfanatic1 0]

Sounds like you pretty well have it figured out to me.  Everything you mentioned is correct and necessary to make a go of using an IB sub setup.  Don't skip over the small holes though.  Covering the big ones like the 6x9 holes is definitely very important but even the small ones will degrade performance if they're not covered as well.  If you were really wanting an SSA sub I think the closest one to fit the bill for you is the GCON.  Fi has a line called the IB3's that are purposely built for IB use and they come in a 15" size.  

 

Stupid question, but arent some of the holes there to allow doors and trunk lid to close properly? So there is no air lock of some sort????

[altoncustomtech 773]

lol, and welcome to the wonderful world of car audio compromise.  I've personally never owned a vehicle that sealed good enough in the first place for that to happen, but technically yes that's what some of that is for.  It allows air to be displaced from the cabin to the trunk or vise versa to facilitate easier closing of the doors, trunk lid, etc., or so I've read.  

 

Personally I'd seal the ever loving hell out of it and then if closing things was any sort of problem.  If it was then I would systematically start with the smallest holes first, one at a time, and modify the seal so that it can pass some air, the smaller amount the better.  Then recheck how everything closes and if need be do another until things closed better without degrading the sound any more than necessary.

 

I didn't bother going too crazy sealing the trunk/rear deck of the Olds because, well, it's a 22 year old car.  It's just not worth putting that much work into it.  Because I chose not to make a great seal the bass below about 45hz and somewhere in the midbass region (from a little testing and guesstimation between 150-200hz) suffers.  Below 45hz is no big deal, I keep it high pass crossed at 50hz anyway because I don't expect these little 8's to have a great amount of authority down deep in an IB configuration.  But the dip in the midbass region hurts it a little.  Not enough to make it obnoxiously annoying or to go through a great deal more work and money to improve it but I know it's there and what's causing it.  It's a compromise I'm comfortable making.  Everything we do in the hobby has pros and cons and we must decide what compromises we can live with and which ones we can't.

[Gnfanatic1 0]

So guys we all agree on the Gcon line for IB setup??? 15" with 600 watts going to it, 4 ohm.

[THX_Elite 26]

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