# Bass in a van?



## shwicked (Mar 28, 2009)

I have been using a 2001 VW Caddy Van as my daily drive for the last couple of years, I am a courier so I spend a lot of time in it. I have therefore put a bit of money into the sound system.

Mids and tweets are great, consisting of a pair of Focal Polyglass 6.5" powered by a Genesis Series 3 Four channel.

My problem is bass, I have tried various SQ subs in sealed boxes, a JL 10 was my first, then a JL 12 running bridged from channels 3+4 on the Four Channel, but neither of these gave the desired result. Just recently I purchased a Kicker 12L72 in a custom ported 2.5Cuft box powered by a Genesis Miniblock @ 1ohm. But still dissapointing results. 

So I'm mucking around with different positions for the sub thinking this maybe the answer and realised that when the back doors of the van are open, the sound is great, lots of depth. Also I found that when the sub is in the cabin say on the passenger seat the sound is also very good. But when the sub is in the back, close the doors and the bass literally vanishes from the cabin.

My issue is that I cannot drive around with either my sub on my passenger seat or with my back doors open, I have tried putting a bazooka tube behind the passenger seat in the cabin, this also sounds OK but it does not produce the depth that I am looking for.

So my questions are, why is the bass not coming through to the cabin when the doors are closed and what setup do I need to work around this?

Your help is greatly appreciated.


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## Candisa (Sep 15, 2007)

Is there a wall between the cockpit and cargo-space or are you willing to install one if there isn't any?

If so, get a good IB subwoofer. My girlfriend has a Dayton IB385-8 subwoofer, she actually wanted 2 of them, but we couldn't find a second one. 
If you can find some place where they still have them (PartsExpress.com has them, but importing to Belgium costs taxes and Intertechnik.de doesn't have them anymore), these would be one of the best options in a van. (Please let us know if you find a place in the EU that still has them...)

Isabelle


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## Volenti (Feb 17, 2010)

Ok, assuming you have the sub enclosure in the usual position in the caro area up against the cargo barrier you're probably getting a lot of cancellation, that's why it sounds better with the cargo doors open.

The solution is either move the existing enclosure all the way to the back of the van so the sub loads against the rear doors (It will most likely be in the way there though, but will suffice to check the result)

Then if you're happy with how it sounds in that position, make/have made a custom enclosure along one wall with the driver+port as close to the back of the van as possible.


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## shwicked (Mar 28, 2009)

There is a thin plastic bulkhead, half mesh half solid but is easily removed. 

After reading up about free air setups it seems like a bit of a minefield to find the right sub, especially that can handle reasonable amounts of power and especially sourcing one from outside of the US! There are all sorts of recommendations about subs that use the boot as the enclosure but not the cargo space of a van. Do you know what sort of specs I need to look at i.e. Vas etc

Is your girlfriends sub in the bulkhead of a van?

Thanks for your help


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## 60ndown (Feb 8, 2007)

are you subs crossed over about 60 hz?

can you do time alignment on the sub?

and exactly where your box is located makes a huge difference.,

Aiming your subwoofer box


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## shwicked (Mar 28, 2009)

Very interesting article about box positioning, I never knew it would make such a difference. It would be a pain for getting stuff in and out of the back of the van if I had to have the sub right at the back by the doors.

Yes the sub is crossed about 60hz.

How would I go about time alignment?

Thanks for your help


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## Candisa (Sep 15, 2007)

Power handling doesn't matter in a sub or in any other speaker. It's the air it can move that counts. A Dayton IB385-8 sub handles only 100-150W before reaching x-max, but with a 15" cone moving 28mm back to front (14mm one-way), you'll get loads of bass, especially in the small cockpit of a Caddy.

Xenia hasn't used the IB sub in the van, because she only bought it a couple of months ago and already sells it again to buy a regular car, but she was planning to mount 2 of those (she likes reggae music) in a home made solid MDF wall between the cargo-space and the cockpit.

Any subwoofer with a Qts of .6-.8 can be used in an IB setup, even if they're not sold as "free-air" or "IB" subwoofers.

greetings,
Isabelle


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## 60ndown (Feb 8, 2007)

shwicked said:


> Very interesting article about box positioning, I never knew it would make such a difference. It would be a pain for getting stuff in and out of the back of the van if I had to have the sub right at the back by the doors.
> 
> Yes the sub is crossed about 60hz.
> 
> ...


i drive a van and have a 15" sub and 1500 watts, with the sub at the very back/rear of the van i get tons of great bass, move the box up to the middle and i get none.even with the sub aimed directly at me in the drivers seat i dont get much.

you have 2 options,

1. put the sub at the very rear of your van, enjoy great bass and deal with loading unloading issues (maybe stand the box on end so its only 15 inches wide?)

2.build some complicated sub design that in the end MIGHT NOT WORK.


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## 94VG30DE (Nov 28, 2007)

How about just switching the phase on the sub? Just swap the wires powering the sub, and see if that helps. That would have been my first step, but I don't see it mentioned.


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## MiniVanMan (Jun 28, 2005)

Nobody is going to state the obvious??? 

Vans are BIG. You don't get the cabin gain from a van that you do a car. Solution? Go big, and aim the sub toward the front of the vehicle. 

You can't rely on cabin gain to get you the bottom end that you could in a sedan or hatch with a 10" or 12" subwoofer. You need a subwoofer capable of a flat response well below 30 hz. Then you port for a flat response down to 25-30 hz. If you go sealed, you'll need an even bigger sub. 

Just one of the issues with working with a van. 

Big sub, ported enclosure. You ain't getting away with some stealth little 10" in a small sealed enclosure.

For example, let's take two fairly identical subs. The Dayton RS 10" and 12". In my minivan, I had two RS12HOs running off of 1400 watts. Chad has one RS10HO running off of about 200-300 watts (I think, may be less actually). Both enclosures are ported. Mine to 26 hz, and his to just around 30 hz. Both built for a relatively flat response. 

Mine are there, but would absolutely be smoked by the output of Chad's one 10" running off of about 1/5th of the power. It's pretty pathetic.

So, OP, you need a stout 15-18 subwoofer with some juice going to it.


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## 60ndown (Feb 8, 2007)

MiniVanMan said:


> aim the sub toward the front of the vehicle.


wrong.

try turning your subs around, you might compete with chad


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## PorkCereal (Nov 24, 2009)

What about downfiring a larger ported box (port forward maybe)behind the seats? It will allow you do load it agains the floor right behind you and you can make the box durable enough so you can still load the van. Maybe coated in bedliner.


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## 60ndown (Feb 8, 2007)

PorkCereal said:


> What about downfiring a larger ported box (port forward maybe)behind the seats? It will allow you do load it agains the floor right behind you and you can make the box durable enough so you can still load the van. Maybe coated in bedliner.


ive tried it and many other variations, 

none are nearly as good as the box at the very back


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## Candisa (Sep 15, 2007)

The reason why a subwooferbox in a van is difficult is because of cancellation.
Say you have a subwoofer enclosure, playing towards the front. 
You not only get the tones coming directly from the woofer, but also the tones that went to the back first and then reflected off the rear doors. With a bit of bad luck, those reflections are between 90 and 270 degrees out of phase --> cancellation!

This is why a subwoofer at the back of a van works (not enough distance to turn the phase of the indirect waves enough to cause cancellation) and why the sub sounds better with the rear doors open (bye bye out-of-phase reflections).
Since a subwooferbox at the back of the van probably isn't very practical if you really *use* the van, and for obvious reasons, you can't always drive around with the back doors open, putting a wall between the cockpit and cargo space with an IB woofer in it is the solution I recommend.
First of all, you won't have those nasty -possibly out-of-phase- reflections coming from the back, since you have a wall preventing that, and...
You make the listening cabin a lot smaller, raising the cabin gain a LOT!

Isabelle


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## MiniVanMan (Jun 28, 2005)

60ndown said:


> wrong.
> 
> try turning your subs around, you might compete with chad


Yeah, you know, because I've never tried that. 

I've only been driving vans with subwoofers in them for 7 years. WTF could I possibly know?


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## shwicked (Mar 28, 2009)

What about what Isabelle suggested? Has anybody tried that route, sounds good in principle, the Dayton subs seem good value, have good write ups and I get all my load space back.

I have tried upping the power, the miniblock is putting out 600wrms, this really should be enough.

I will try re-positioning the sub at the back of the van and firing it towards the rear this evening and let you know.

I feel the key is in what Minivan was saying about cabin gain, it feels as though I am getting cabin gain in reverse with the sub being in a large area and me being in the smaller cabin area of the van(if you look at a 2001 caddy you'll see what I mean) and what Isabelle was saying may fix this.

Thanks everyone.


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## PorkCereal (Nov 24, 2009)

Custom build fiberglass enclousers into the rear doors?


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## shwicked (Mar 28, 2009)

Just read Isabelles last post. I think I am going to go down the IB sub route. I know there are lots of threads on IB subs but while we're here, any suggestions on a good IB sub, seems the Daytons might be quite expensive to import to the UK 

Thanks


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## MiniVanMan (Jun 28, 2005)

shwicked said:


> Just read Isabelles last post. I think I am going to go down the IB sub route. I know there are lots of threads on IB subs but while we're here, any suggestions on a good IB sub, seems the Daytons might be quite expensive to import to the UK
> 
> Thanks


Yeah, that's the best route. Issue is you have a wall between you and the back of the van. If that's not a problem, then great, go with that solution.

When I was saying point the sub forward, I forgot to mention you need the sub in the forward section of the van as well. All of that solved with a wall. 

Here's an option. I guess it really comes down to shipping. 

DIYCable.com : Intro » Home » Exodus Subwoofers »


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## 60ndown (Feb 8, 2007)

placing box in rear of vehicle = 10 minutes and $0.

building a wall that will not flex or leak = days of labour and $$$$$ materials

your choice.


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## Candisa (Sep 15, 2007)

I talked about it with Xenia, she isn't willing to sell her Dayton IB385-8, she'll use it herself in her "new" car.
That Exodus has a lot of x-max and a perfect Qts for IB, so that would be a great option and not that much more expensive compared to the Dayton if you have to import from the US anyways...

Isabelle


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## 60ndown (Feb 8, 2007)

MiniVanMan said:


> Yeah, you know, because I've never tried that.
> 
> I've only been driving vans with subwoofers in them for 7 years. WTF could I possibly know?



you said recently that you do almost all of your listening *parked* 

its easy to get enough bass to satisfy when parked.

im guessing this courier might like some strong bass when he's actually driving ....


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## Volenti (Feb 17, 2010)

If you are contemplating building a solid wall to allow the use of an infinite baffle sub, and are already happy with the space your current enclosure takes up in it's current position, why not combine the two, "wall the van" like is typical of SPL vehicles, only with an enclosure set up for SQ (or using your current one, if both sub and ports are on the same face).


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## MiniVanMan (Jun 28, 2005)

60ndown said:


> you said recently that you do almost all of your listening *parked*
> 
> its easy to get enough bass to satisfy when parked.
> 
> im guessing this courier might like some strong bass when he's actually driving ....


What drugs are you on? $500.00 if you can show me where I say I do almost all of my listening parked.

The only time I do my listening parked is when I'm in a traffic jam. 

Just shut up now. You're coming across more retarded than usual.


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## Candisa (Sep 15, 2007)

Volenti said:


> If you are contemplating building a solid wall to allow the use of an infinite baffle sub, and are already happy with the space your current enclosure takes up in it's current position, why not combine the two, "wall the van" like is typical of SPL vehicles, only with an enclosure set up for SQ (or using your current one, if both sub and ports are on the same face).


That's a fantastic idea if you don't want to be limited in your choice of subwoofers by the Qts parameter


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## ryan s (Dec 19, 2006)

How full does the van get? In an IB config, the parameters will change depending on the stuff in the back.

Wall it off (if you don't mind a wall), throw in a couple 15s, add a few hundred watts, good to go. The Caddy is pretty small but it's still a van. Even with it half full, you should still get decent performance, I'd think.



MiniVanMan said:


> What drugs are you on? $500.00 if you can show me where I say I do almost all of my listening parked.
> 
> The only time I do my listening parked is when I'm in a traffic jam.
> 
> Just shut up now. You're coming across more retarded than usual.


:laugh:


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## shwicked (Mar 28, 2009)

Good idea Volenti, however the Caddy isn't massive. With my current box I can remove it completely if I need to put a pallet in the back, if I wall it off another metre back to accommodate a sub box that seriously compromises my load capacity. Permanently mounting a sub in the bulkhead will only lose 8-9 inches depending on the depth of the speaker, OK it won't be as SQ but I think this is the best of both worlds. There must be a good IB sub that's easily available to the UK market. Just looking at a 15" FI.


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## ryan s (Dec 19, 2006)

That's the advantage to a "wall" or a "baffle"...it's just...a wall of wood :laugh:

IB is "as SQ" as any other sub enclosure  Cone area is what you need...the more, the better.


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## Greg S (Oct 21, 2009)

Is it possible to mount a sub between the front seats, or possibly do a couple shallow mount subs behind the seat in a fiberglass enclosure? This way you get the advantage of having all of your cargo room and the sound you get with the sub on your passenger seat. I've had great luck with a pair of 8s sealed between the seat in my minivan, but I think I have more room between my seats than you do.


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## bobduch (Jul 22, 2005)

Many years ago I put a 12" sub in a sealed box and recessed the box into the rear door of a friends van (Chevy Astro van with "barn" doors). Only stuck out 5.5" from the rear door. Worked pretty well.

In my Honda van the Velo is between the front seats.


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