Hello,

I was wondering about adding a shallow mount sub in my car due to not wanting to sacrifice my trunk space. I searched about this subject but couldn't find any definite answers regarding these subs. Some say they are all good, some say they are crap.

Does anyone have any input on this? I know that truck guys use this due to limited space and they like them. I would have the sub mounted right behind the ski hole so it would go right into the cabin.

just any input on this would be appreciated

 

I did something similar to this in my old car. I mounted an 8" sub over the ski hole facing inside cabin of the car. The trunk alone seemed to be enough of an "enclosure" to give the perfect amount of base to suit me. It was very easy to do, just took a piece of wood cut out the hole for the sub and mounted the piece of wood over the ski hole. Could be a pain though if you have kids that could pull down the arm rest and mess with the sub. just my .02

 

I want point out that its not just the shallow shape of the sub, but also the ideal airspace requirements you want to pay attention to. Surprisingly, many shallow subs require huge airspace, which doesn't help.

Off the top of my head, the new Alpine Type R shallow, the Exile Audio 10 (got one, love it), there might be a few basic brands like Polk MM, or Kicker that would work. The new Fi Audio SSD is coming out, it is going to be a neo-magnet motor sub and might be pretty shallow. Looking forward to trying that. Just another thing to remember is that the sub wiring into the ski pass isn't actually going to sound much different than the sub being somewhere else in the trunk. Bass drivers pressurize the entire cabin in general. Ideally if you could take the factory sub out of the rear deck and then build a box that fires backward into the trunk,..this should give you the strongest bass response. It is also quite easy to build!

 

Yea I was thinking of doing this as well, infinite baffle. But the sub needs to be specifically designed for this set up in order for it to work well. And those are not that easy to come by and they are also pricey because I am in Canada and I would most probably have to get them from some site from US. And no I don't have kids so that's not a problem.

I was thinking that mounting it there wouldn't cause as much of a trunk rattle as it would be mounted right in the back there. Also mounting it in the back deck and building a box there, how small would the box have to be to fit there. I am not sure how that would look or how it can be done. I know that shallow mount subs would have to have adequate airspace, but the box can be made thinner but wider. For mounting a 12" rockford fosgate shallow sub, it would be 19.5" x 17.7" x 8" thick. 8" is nothing, nice and flat.

 

I highly encourage you to do some testing with a basic box then. Face it forward, backward, etc. Play the same song, take notes on what you hear.

My educated estimate is that the rear-firing sub will sound better.

 

which way the sub faces isn't even issue here. I was just wondering on opinions on shallow mount subs. I am just looking for some more bass and some more kick as stock sub sucks. Not looking for anything too crazy, like redoing my whole sound system.

 

IDK about that, it all goes together. Stock sub location is one thing, an custom box is another. BTW, here's some canadian websites

http://www.creativesound.ca/index.html

http://www.solen.ca/pub/index.php

Those two companies sell great home theater gear and that works just fine in home too, if you know what you are looking for.

 

If you want some suggestions on shallow mounts go to google. Actually do some research

 

^^^that was helpful.
patient: "I have chest pains"
emt: hands patient a textbook on the body's cardiovascular system.

I've been interested too because I'd like to regain my trunk space but when I DO want it, I think I'll miss the power of 2 12's!

J.

 

someone snap a pic of what the stock sub location looks like for me. Is it the same as Gen2 or are we talking a whole new ballgame?

BTW, take look at Bing's work on the 3rd gen. Obviously that's how you do it (when you want to go all-out.)

 

If space is a concern, go IB. We can easily put 2 12's there.

 

We normally install a Clarion 10 flat piston sub in the stock location & build a small box underneath it and put more power to it. It's really impressive!

 

I was strongly considering doing this when I saw niebur3's build thread. But considering that I would need to sound deaden the whole trunk, seal the cabin from the trunk, and actually get subs that work well in that enclosure, makes it a much much more expensive project than what I hoped to do. Also I am in Canada and it's hard to get a full range of subs up here so I would have to order stuff from US and shipping and duties are insane. ex. IDQ12 159$ shipped in US. To get it to me final price 320$. You see the difference there.

I have to take all this into consideration because I don't have unlimited funds for this.

 

thanks but I did do some research. There are people that like it and some that don't. Like I said, truck guys like it, because they really have no choice. So I am asking about running one in a box, in my trunk. Would it be a good idea or not.

Other threads on this forum about shallow mount subs are all about replacing the stock sub, and mounting the shallow one in the same spot. Which I am not interested in.

 

Someone already suggested this but I am having a hard time picturing it. I couldn't find any pics of this either (didn't look hard enough I guess). What I hate about the sub mounted in the stock location is the rattle I get from the back deck cover. And I think that no matter what I do, I will always get that rattle from it so I am skeptical about mounting the sub in that place.

 

Yeah about Image Dynamics... they are done for.

Like I showed Myron there are two Canadian-specific sites that will rock your socks, man. CSS is awesome stuff, and Solen has EVERYTHING.

 

Only other way to save space is build a fiberglass corner pocket(pricey) or go with a small 8" in a 4th order and fire it thru the ski pass.

=(

 

I think I am gonna stick to the shallow mount sub, 8" thick box, mounted behind the ski hole. Attached to the trunk floor and the extra piece of MDF that's gonna be kind of like an infinite baffle setup, except with a box behind it. Then attach the amp to the mdf as well if there is room and make a fake back cover so when you look in the trunk, you don't see any of this. Well that's the idea for now but I am not gonna do this right away so plans might change

 

IF you are doing that make VERY sure the sub is blocked off to the ski-pass only, else the space you leave in between will set up a series of cancellation nodes that will severely screw up the frequency response.

OR, you could listen to me a for a second and pull the stock sub , and install the box backwards into the trunk. This would let the trunk load the sub instead of cancel it, and this effect would be improved if the sub were corner-loaded if possible.

Again, can someone show me a pic of the stock subwoofer IB opening?


IB is IB, and sealed is sealed. But room nodes are a big issue and there's a reason home theater subs don't sit in the middle of the room.

 

I have seen some members do this kind of setup, where they mount the sub facing the ski hole and I didn't read anything about them having problems. I am a noob at this and I am learning.

 

Well I'm not a noob by any stretch, and I can tell you that if you have a subwoofer, you have to think like a subwoofer. It doesn't produce high frequencies, it compresses air like a pump. So what you want to do is get the air pump to not cancel itself out as much as possible. That's why subs are usually in a box, so the rear wave doesn't collide with the front wave and create cancellation. The lower the frequency, the longer the wave, and the more important this all becomes. IB subs (ones that mount without a box) need their front wave and back wave to stay separate, else cancellation rears its head.

Putting a sub into the trunk, so long as the factory sub or at least some openings in the deck are available, will let the sub compress the air in the cabin just like the air in the trunk. If the trunk is completely sealed off like some cars are with their gas tank behind the seat, then you could run into issues. Because I've not seen the 3rd gen trunk up close and personal, I am assuming this is what it looks like:



If so, just remove the stock sub, put some grille cloth in the hole to keep light intrusion down, and install a sub box in the trunk preferably in a corner or at least firing backward.

Yes, you should invest in a little bit of deadening material, because resonance will be an issue anytime you are compressing the air in the car. Yes, that means the top deck should be deadened a bit. A few quick high quality tiles (read: not asphalt-based junk) of the SDS product, Second Skin, Raammat BXTII, etc. etc., and you're good. You can also add a little anti-rattle foam (like weatherstripping materials) in between squeaky items, which is just improving what the factory failed to do.

BTW, you will find that if you can somehow get the subwoofer very near the back of the trunk firing backward (which is inefficient for storage in the trunk but I am just making a point), you will find the output is most likely the strongest. There is a bit of physics that goes on in all of this, and it turns out that the least bit of cancellation occurs when the subwoofer has a very early reflection off the rear of the car, and then the pressure wave makes it through the car.

If you feel like proving some of this on your own, not only do I encourage it but I also think it would help end the debate relative to this exact vehicle. You see, there is a countless lineup of articles online complete with SPL testing, to prove the theory I outlined above. But actually, each car is different so quite literally your results may vary. Only by doing a live test with an SPL meter, some sine wave tracks, and a piece of graph paper can you prove it for this car.

To test, what you would do is build a simple box (or buy a pre-made) and stick a subwoofer in it. Then go out to an open area like a quiet field, run some long speaker wire from your amp to your subwoofer box outside of the car, and get about the same distance away from the sub as you would be in a car with a simple SPL meter. Play at a known volume that is not going to kill the amp or the sub, and track on a graph paper or some form of record-keeper the SPL level for a number of given track frequencies. Typically 20hz, 25hz, 30hz, 35hz, 40hz, 45hz, 50hz, 60hz, 70hz, 80hz, 90hz, 100hz, 120hz, and maybe a little above. The graph or table you draft out in this open area can be considered your "anechoic" or non-cabin gain subwoofer output. Now, simply take the subwoofer and put it in the trunk, get your meter in the car close to where you'd consider your ears to be, and test out all sorts of positions and locations. Sweep through your tracks and mark the SPL of each frequency just like before. Keep in mind that open or closed windows will affect the response! So pick which way you prefer to drive as your primary, and measure that way. You will find that relative to the outside curve, the inside curve will be MUCH louder. That's cabin gain, the effect of the sub inside an enclosed space. Again, that's physics for you, it is constructive interference working to your benefit. From there, the dips in response relative to the loudest result overall is the effect of cancellation interference, which will likely be the strongest in the lower frequencies with the box facing forward, and the least-noticeable with the subwoofer box in the rear-most portion of the trunk facing backward.

Also through this testing (which should only take an hour or so, despite the effort it seems like while typing this all out to you), you will find the resonant points of your vehicle. These resonances will be at a harmonic (a fraction of the original frequency) and will be noticeable at specific frequencies at different parts in the car. If you note where they are happening perhaps on an outline of the car, you can later add deadening and anti-rattle materials exactly where you need to in strategic places to stop the resonances that matter.

I hope this helps and I hope others later on read this thread, because I'm not doing that again. LOL.

 

Noob, you are not.
But I agree...I messed around with my 12's for a while...tried ported, facing forward and back, then back to sealed box. DEFINITELY got the best response from both of them sealed facing back (garbage audiobahn subs)...
Left them that way. I wish I knew enough to eliminate the box altogether and have a sub in the stock location that I could turn up and FEEL. But like you said, it's about moving air...and you just can't move the same air with a small bike pump as you can with a standing one.

J.

 

Oh I've got an idea for your stock sub location if you can snap a shot of its underside. A plenum of 2 Acoustic Elegance IB subs in a V or l l configuration http://aespeakers.com/news.php?start=0&news_id=26
Or just one in a stepped plenum

The stock opening will serve both subs, and the trunk will need to be well sealed off (which shouldn't be hard.) The plenum will allow the subs to hang off the deck, which should be reinforced a bit w/ some strong ply and of course deadening/sealing materials. Full trunk space achieved (less the sub(s) poking out a bit.

I need a shot of the underside of the trunk spot with the sub to make this a reality.

 

Do a 8" JL W1
Small sub for what you need and in the right box I've heard one of these pound.
Also not an expensive sub and easy to get a hold of for you.

 

these subs take month upon months to get after ordering. In the 3G section there is a thread about a guy waiting on his IB15s for a very long time.

 

I was thinking more of a 10" at least, 400-600watt in that range somewhere.

 

Na uh. Jl's lower line sucks ass.

Only 2 8's i'd get are the tc epic & the sundown sa-8

 

Yeah I know, I was part of the wait as well. But John's got his stuff together now (it was a wait for parts, not a wait to get in line.)

Besides, the new IB sub I linked you to won't take very long.


Man you really gotta learn to trust me.

 

haha no man I am learning a lot as you seem to know your stuff. But you have to take into consideration that I would be paying close to 400$ for that sub if not more. Just for the sub. I'm in Canada ey haha. And for my needs that's way more then I can afford or wanna spend.

 

That 400 is worth it.

 

This isn't shallow, but it IS Canadian, and it is awesome

http://www.creativesound.ca/details.php?model=SDX10

 

Maybe so but I feel like I am getting scammed paying 100-150$ for shipping and duties. If I run into some used ones or some that are in Canada already, that would be great. But this way I don't think so.

 

I was actually checking out that site and stuff they had.

 

IMO one of those in a simple, well made box facing backward should be TITS.

 

That css is awesome for the price.

xbl + triple shorting rings(i think) so sq should be top notch

 

Small box friendly as well!, or you can pony up some space and go ported. Its a great sub from what I hear. And its Canadian, eh?

 

So what kind of an amp would I have to run with this sub? I asked them for an opinion on resistance, watt.. and they just said this is not a sub for a car and if you run it in the car ask for opinions on forums if it'll work and with what amp. And I can't find anyone running this amp in the car (well at least google search didn't give me much)

 

for 1, 300-400 @ 4 ohms
for 2, 700-800 @ 2 ohms

 

thanks that's perfect info, plain and simple

 

Your crunch amp will be just fine btw.