Shed some light and knowledge upon me please

[mpunklil 0]

Let me introduce myself first, hi my name is Matt lol. This is going to be a long one, so let me apologize in advance. I started car audio when I was 16 and started teaching myself stuff through Car Audio mag and Crutchfield lol. My first "system" consisted of a Panasonic deck, some kenwood 4x6's in the front, a Profile Baja sub amp, and a Pyle 8" cut into the bottom of a 5 gallon water jug in my prized 79 BMW 320i...Sad huh? I ended up going with four 10" Hollywood Sound Lab Excursions and a US Amps Exterminator 100 I think, dB dragged once and got a best of 124.8 lol. Anyways, I got a job at Circuit City as an installer at 17, learned a lot. Worked for Circuit for about 1 year installing, then Best Buy for 2 years, then BACK to Circuit for another year. I knew my stuff though, and I still do but I'm just behind the game a bit. My last system (2004ish) consisted of a carputer, JBL GTX47, JBL GTP4, three MTX BlueThunder Pro 400x5's, one MTX BlueThunder Pro 300x2, older MTX Thunder pro highs in a 3 way setup for both front and rear, three MTX Blue Thunder 8's, and a Crystal Mobilesound CMPx2 15 in a 2.0cuft sealed box(limited on space). Everything was active crossover, 3 batteries, blah blah blah. All of that in an 89 Bronco II. It was a pretty slick setup in my opinion, definitely not a regular setup from what I was used to seeing in the retail b.s.

Here is where I need some light shed...its been about 5 years since I have built a system for myself. My current vehicle is an 04 Audi S4, stock setup. I am at a total crossroad as to what to buy, but out of being a little to anxious I have already started picking up amps when I get a chance. Currently I'm sitting on three Sony XM-404EQX's, and two Sony XM-2252HX's. Yeah I know, hang me for buying Sony but I know those amps aren't that bad from my personal amateur experience and I love they way they look. I have a kid, I need the trunk space, and the S4 trunk is pretty tiny when you start shoving boxes in it. I originally wanted to shallow mount some 10's, and maybe 12's if I started getting creative. I know its possible, but finding a shallow sub in an infinite baffle setup that is going to sound good just doesnt even seem possible. I noticed FI has an infinite baffle series, but I have no idea how they sound, where I could hear the setup, and if I would even be satisfied with it. If I went with an IB setup, then I also am going to have to start glassing side panel in the trunk to hide the amps...if its gonna be stealth, then do it right. That leads me down the road of a false floor setup. I like this idea, especially if I can stuff an Incriminator DP 18, or even that sweet Incriminator DP 21 BUT, if I got an 18 or 21, then I'm probably going to need to stuff some IB 8's in the rear deck. What effect am I going to have on those 8's in an IB setup, rear of cone facing into the trunk, when I have such a large woofer moving air inside of the trunk? Am I barking up the wrong tree here? Should I cut my losses and just do a simple 6.5" speaker all around, IB 10's in the rear deck, and call it a day? It would certainly save me some weight, but I'm not sure I would be very happy with the final product. If I went with a false floor, the sub needs to be in a sealed enclosure, I really dont feel like dealing with porting a false floor anytime soon lol.

BTW, the main genre's of music I listen to would include groups like DJ Tiesto (techno), Children of Bodom(metal), and NOFX(rock). Yes, I understand that it is an odd mix.

I am very sorry for this lengthy post, but I felt it was needed in order to get some accurate responses and real opinions!

So,

A: Simple setup, and please give suggestions

B: False floor setup, suggestions as well

[emh9009 199]

What are you goals with this new system? Stealth, but great quality of music? or do you want loud? if you post the max dimensions you are willing to give up in your trunk, im sure someone can form a box for you, depending on what size sub you want/space required. i would say keep it simple, that way if you dont like it it will be easier to change. But buy what you know you will enjoy, so that isn't even in question.

[mpunklil 0]

Sq and loud as can be...bottom bass extension not as important as clean hitting bass on a kick drum, but it would be nice. I do not want to throw a box in the trunk as I will have no space for a stroller. I did a real rough calculation, and figured I can build a false floor with around 4cuft. It will require the removal of my spare, and upgrade to runflat tires...which is fine, I plan on doing that anyways. I should mock up a box setup for the rear deck and see what I can achieve, but that is going to require shallow subs. Where can I hear Fi's infinite baffle sub in southern california?

[Dictator1992 6]

Least your closer to the fi Factory then i am (( Sc.........

[eggyhustles 33]

infinite baffle?

[Tirefryr 1,742]

You are getting a little too anxious IMO. Forget the 18 or 21 idea, hell even 15 if you want trunk space.

Pretty much any driver will work in an IB alignment, you just have to make sure you do all your homework and do as much as possible to completely separate the front and rear waves. I think this is your best bet here. I don't know what the deck looks like in that vehicle, but you seem to want something with a little bit of volume, so I would try to fit a pair of 10s or 12 in the deck IB, and work the rest out from there. No need for an enclosure taking up room and gives you many options with amplification. The effeciency and low(er) power handling of the IB system nulls the need for a large sub amp which eases the strain on the electrical system which means less money on wire, batteries, alts, and cooler temps.

It's a no-brainer.

[mpunklil 0]

You are getting a little too anxious IMO. Forget the 18 or 21 idea, hell even 15 if you want trunk space.

Pretty much any driver will work in an IB alignment, you just have to make sure you do all your homework and do as much as possible to completely separate the front and rear waves. I think this is your best bet here. I don't know what the deck looks like in that vehicle, but you seem to want something with a little bit of volume, so I would try to fit a pair of 10s or 12 in the deck IB, and work the rest out from there. No need for an enclosure taking up room and gives you many options with amplification. The effeciency and low(er) power handling of the IB system nulls the need for a large sub amp which eases the strain on the electrical system which means less money on wire, batteries, alts, and cooler temps.

It's a no-brainer.

I'll agree, it would be nice to not have to upgrade to multiple batteries...I might toss a batcap in for the hell of it. Stock alternator pushes 180 amps, but not sure what the draw is on the car. I would assume the vehicle draw has to be a bit beefier in order for Audi to put that big of an alternator...my clamp on meter is at my dad's house currently. Already have some Stinger 1/0, and distrobution blocks. I'm starting to lean more towards infinite baffle now, and isolating the trunk shouldnt be too hard. I already started isolating the stock sub in my desperate attempt for a little more bass lol. Who else has a decent infinite baffle sub other than Fi? I understand any sub could work, but I would prefer a sub that is already designed for such thing in order in order to cover any mistakes I make in calculations

[mpunklil 0]

Oh, shoot me again...im keeping the factory deck. Converting the front and rear line out off of it to RCA using the Soundgate LOC2's. Changing the headunit is not an option for me

[95Honda 486]

Does your S4 have the fold down section in the rear seat for skis and things like that?

I have done IB installs where I built a funnel, well more of a reducer, out of fiberglass that fed the sub straight into that hole. Drop the armrest and, bam.... IB bass out the ass. I think I used a few 12" pioneer IMPP free air (high Q) subs like this... This was about 10 years ago..... Sounded pretty good, really... I wish I had pics.

Nice thing about the German cars is the trunk is sealed off real well and is good for IB.

[mpunklil 0]

95honda, yes it does. Just to clarify, you funneled the back waves of the sub through the ski bag area into the front?

[Tirefryr 1,742]

95honda, yes it does. Just to clarify, you funneled the back waves of the sub through the ski bag area into the front?

You could do it either way.

[mpunklil 0]

Hmmm...well the whole goal in the end is a usable trunk, including folding down the seats. Maybe what I am envisioning from what 95honda said is not what he meant

[mpunklil 0]

Votes are at 50% A, 50% B lol

[Impious 1,476]

Does your S4 have the fold down section in the rear seat for skis and things like that?

I have done IB installs where I built a funnel, well more of a reducer, out of fiberglass that fed the sub straight into that hole. Drop the armrest and, bam.... IB bass out the ass. I think I used a few 12" pioneer IMPP free air (high Q) subs like this... This was about 10 years ago..... Sounded pretty good, really... I wish I had pics.

Nice thing about the German cars is the trunk is sealed off real well and is good for IB.

Something like this?

As to your original question; I agree with the others. For your goals, a nice single or pair of 12's IB would be more than sufficient. Keep it simple. I run a single Shiva-X IB in my vehicle (not the Dcon pictured, that was just for the review) with what I would consider to be great results. And the baffle is painted black now so it looks a lot better

Oh, and I can still fit anything I want in my trunk, which was also my goal.

EDIT: I missed the part where you wanted to keep functionality of the folding rear seats. You could hang the subs from the rear deck firing towards the rear window, just won't have much bass with the seats down.

[mpunklil 0]

Does your S4 have the fold down section in the rear seat for skis and things like that?

I have done IB installs where I built a funnel, well more of a reducer, out of fiberglass that fed the sub straight into that hole. Drop the armrest and, bam.... IB bass out the ass. I think I used a few 12" pioneer IMPP free air (high Q) subs like this... This was about 10 years ago..... Sounded pretty good, really... I wish I had pics.

Nice thing about the German cars is the trunk is sealed off real well and is good for IB.

Something like this?

As to your original question; I agree with the others. For your goals, a nice single or pair of 12's IB would be more than sufficient. Keep it simple. I run a single Shiva-X IB in my vehicle (not the Dcon pictured, that was just for the review) with what I would consider to be great results. And the baffle is painted black now so it looks a lot better

Oh, and I can still fit anything I want in my trunk, which was also my goal.

EDIT: I missed the part where you wanted to keep functionality of the folding rear seats. You could hang the subs from the rear deck firing towards the rear window, just won't have much bass with the seats down.

Wow, I cant believe I couldn't mentally picture that hahahaha, somehow I was envisioning subs mounted on the rear with a fiberglass "funnel" off the back of the subs "porting" into the armrest hole. I have tossed the idea around also of doing a baffle wall against the rear seat, but I think I would be happier knowing I could fold the seat down when I needed to. Also, even if I did a rear deck setup, then Im going to need a board behind the rear seat in order to separate the waves. Probably some 1/2" mdf on the back of the folding seat and sandwich it in between the seat and trunk opening. Those are minor details and requires me to make those decisions once I have decided for sure on infinite baffle.

I was reading this build thread:

Maybe I need to hit the books and read up on why this happens, but can somebody explain to me the impedance rise on an infinite baffle setup and how to avoid it? Or is that non existent and he simply messed up somewhere. Technical explanations are welcome as always

Impious, do you have a pic of your trunk? Thanks!

Edited September 8, 2010 by S4 Matt

[95Honda 486]

Yep, just like the picture.... If you made the baffle thin enough, you could still fold the seats down, you would just have the back of a woofer sticking out...

[effse7en 2]

Yep, just like the picture.... If you made the baffle thin enough, you could still fold the seats down, you would just have the back of a woofer sticking out...

this is what I was thinking as I read this. Just make some sort of large rubber gasket that will seal up against the seat backs when the seats are closed.

Or possibly even mount the sub to the seats, that could possibly work, and then you would still have your full opening when you fold the seats down, you would just have to worry about hitting the magnet.

[mpunklil 0]

Ok I'm more convinced about IB now. I just emailed Fi to see if they have somebody in southern california that could demo the IB3 sub for me