Ok, I have a weird one here. I just installed Boston Acoustic s95 6x9's in the rear of my '06 MC. I have the stock Boost stereo without any type of subwoofer or amplification. With the windows rolled up, the bass is weak to say the least. With the windows all the way down, I get plenty of bass and it sounds really nice. The stock speakers sounded better with the windows up.
Has anyone encountered anything like this?

I'm not expecting thumping bass without a subwoofer, but WTF? Why would this happen??

 

It is all based on the volume of the interior of the car.

I would have expected there to be a small change but the amoutn you seem to be talking about is just not right.

Recomendations:

Check the polarity of the wiring to the speakers. They must both be the same. If this does not rectify the problem then swap the + and - on both the speakers. They may be out of phase with the fronts.
In which case the description above could happen.

Then report back to please. if these do not make a change then that will give me more data to trouble shoot with.

 

all the subs ive had in my MINI, normal box on the back seat firing at the hatch, my wall, etc, all sound louder with the windows down.

sunroof open though = no bass.

 

Thanks for the reply. I will give your recommendations a try. I should be able to get to it tonight. I will definitely let you know the results...

Thanks!

 

Think of your car interior as a bandpass box with sealed subs

sealed to sealed = reduction in bass
sealed to ported (i.e. windows open = more bass
you will find that changing how far the windows are open will alter the sound (aka the tuning of the box)

 

Sorry it took a few days to get back to this thread...

schatzy62, I tried your recommendations and no dice, it still sounds like crap.
D3moN, I sort of figured this is what's going on. The stock speakers with my iPod sounded ten times better. Am I expecting too much from the stock H/U with decent speakers? Should I just throw more bass (subwoofer) at the problem? Although I enjoy driving with the windows down, Fall and Winter in Chicago can be brutal with the windows down!

 

You might be able to "tune" your box to sound better in your car

aka find the resonance value of your car and try to match it by tuning you box and speakers to match that.

http://www.ajdesigner.com/phpsubwoof...quation_fs.php

 

Some people also find that keeping them out of phase is also good depending on the shift just have to play with it really

 

I have a stock H/K system and the bass is more powerful with the windows down or the sunroof opened. The car must be well sealed preventing the required air movement for booming bass when all closed up.
[what d3mon said]

 

It doesn't prevent just changes Think of it this way if you seal a sub box it would be much more sealed than any car and yet can produce wonderful bass. but changing the size of the box changes how much and what kind of sound you get. Well you car is large and changing the volume of the box or type open windows add passengers ... will change the box.