Car Subwoofers

[Lucky]

I've got 1 12" sub in a bandpass box in my trunk...should the sub (and ports) be against the trunkwall facing me or the other way around, with the plexy (and ports) facing the rear of the car?


edit:

HERE is a diagram of what I want to do. Currently the amps are just mouted to the sub (bad, I know) and the box isn't bolted. I'd like to added the MDF stretching across from side to side to seal off the area behind for three reasons:

1. Contain rattles
2. Looks
3. The practicality of being able to use my trunk more efficiently.

A front view would look like this

anyone have any thought about this or which way my sub should face?

 

[Spoooon]

Try both ways and see what sounds better. I ended up facing mine to the rear. In my old car, I had a 15 that sounded best facing the front of the car.

 

[tigerbait]

I've always had better performance with the sub facing the rear. Try it and see.

 

[Lucky]

?

 

[Spac3d]

I am not sure about bandbass boxes, but usually subwoofers are louder when they face the rear of the car (read, facing the bumper). They do loose some quality, but it is the best of both worlds. If you face it forwards, it will sound clearer but you will loose a lot of loundess. People seem to keep tht box about a foot from the the rear of the trunk with whe sub facing the rear. Face it differnet directions and keep it the direction that sounds the best to you.

Are you saying you want to make an amp rack? Before you do all of that, I would say bolt your sub box down. If you are going to build anything, do use 3/4" MDF. I don't really understand the diagram you drew, I'm sorry. You want to mount the amps to the MDF that is connected to the rear of the seat? If you want to control the rattles, you are going to need to use some sort of damepning material, dynamatt, rammatt, brown bread, etc. That will really kill the rattles and make your system sound much better.

Spac3d

 

[Doodoo]

Spac3d has it right about the sub...if it faces toward the rear..it usually sounds louder, but if it faces foward it'll usually sound better. 1/4" mdf would be fine for sealing off the area behind the sub. Your diagram shows the amps being mounted behind the sub...only thing with that is it might be hard to adjust the settings with them back there....also might have some overheating problems...but i doubt it though.

 

[Lucky]

Are you saying you want to make an amp rack? Before you do all of that, I would say bolt your sub box down. If you are going to build anything, do use 3/4" MDF. I don't really understand the diagram you drew, I'm sorry. You want to mount the amps to the MDF that is connected to the rear of the seat? If you want to control the rattles, you are going to need to use some sort of damepning material, dynamatt, rammatt, brown bread, etc. That will really kill the rattles and make your system sound much better.

All the MDF is going to be used for, is as doodoo says, for sealing off the area behind the sub. . I want, basically, a false trunk back from which my sub box would hide behind and which my amps and CD changer would mount to. From what I've read, if I seal the air good enough it should prevent parts of the trunk that are in front of the sealed area from rattling. Yes, I'd still some use some dampening material. I would have access to the controls as my rear seats folds down.

If you dotn understand the diagrams, the first one is as if you are looking down at a cutaway of the trunk. The second would be as if you are looking eye level at it from the trunk opening.

Point taken on bolting the sub box down. From what I understand you are saying, it will be louder if I point it towards the rear but be a bit tighter and better sounding if I face it towards the front of the car. Correct? Of course that may not matter If I put in the sealed amp rack (if you want to call it that).

 

[Spoooon]

Well, with a bandpass box it won't really ever sound as clear or as tight as a sub in a sealed box. However, since you are building a false wall, I think you have no choice but to face it to the front of your car. By front, I mean the ports.

edit: What do you have in your car? Brands and wattage and so forth. Whenever you get around to getting this thing built, take pics.

edit2: Where are the ports on your box? On the top or the back?

 

[StattlichPassat]

I've gotten the best responce out of a JL Audio 10W-0 (10") in a bandpass box with the sub facing up towards the roof and the port facing the front of the car. Just play around with the placement- it will sound like crap or gold in various locations and positions.

 

[Lucky]

Originally posted by: Spoooon
Well, with a bandpass box it won't really ever sound as clear or as tight as a sub in a sealed box. However, since you are building a false wall, I think you have no choice but to face it to the front of your car. By front, I mean the ports.

edit: What do you have in your car? Brands and wattage and so forth. Whenever you get around to getting this thing built, take pics.

edit2: Where are the ports on your box? On the top or the back?

Hmm...I think the ports are on top, let me go check. Yep, on top.

The setup is nothing spectacular, but I think decent. Mostly sony xplod stuff (please, no crapping.) the 4 channel amp is 60x4 and the sub amp is a 2x100 bridged to drive 200x1. Qlogic bandpass box, I think.

I'm off to home depot to buy the MDF....I'll see what I can come up with.

 

[Spoooon]

If the ports are on top, I would have the front of the box (plexi) facing the front of the car.

 

[glen]

Let's see if I can make any sense out of this.

The direction doesn't matter, unless it is crossed over poorly and high frequency (directional) sounds are leaking.

What matters is the center of movement relative to the nearest walls.

You want the center of the speaker movement as close as possible to the corner as this will minimize destructive interference. Nousaine - 1985 AES if you want the paper.

It is possible you could get the drivers close enough to a wall that you create turbulence, which would be bad. Ideally get one of the walls of the enclosure flush with one of the trunk walls and don?t directly obstruct the ports.

 

[Lucky]

Hmm...I think I'm understanding you but if I keep the ports facing up (towards the sky) then they will be 1-2" from the roof of the trunk. That seems like its obstructing the port like glenn said. So would it be better to have the ports face sideways? Or perhaps lay the box on its back and have the ports facing the front of the car?

Thanks for the help guys, I appreciate it.

 

[Lucky]

got 90% of it done....hooked it up and touched power with ground and I blew the fuse on my amp. Will have to wait until tommorow until I can run to best buy and get a new one before I can post pictures. Also, anyone have any idea where I get the generic trunk carpet? YOu know, flexible dark grey....????