bottom mounted speaker box

what are the pros and cons of this type of box .. i was looking to get one because my current box rattles the **** out of the plastic on the inside of the hatch.

You mean a down-firing configuration ? Given the same power and same sub I don't think just switching to a down-firing box will stop something from rattling .

Yeah regardless of if it is facing the hatch or not its going to rattle.

Just find a way to fasten the hatch down tighter.

oh, ok .. then whats the point of a box like this? when i pointed my speakers toward the front of the car the plastic doesnt rattle, the hatch itself does but im not worried about this because i cant hear it when i am in the car.

Sound deadening your hatch would seem a lot more productive and easier.

that does make sense .. but dont you deaden the actual metal? what could i use to make the plastic from rattling?

Try using some dynamat-like product applied to the back (or any unseen portion) of whatever panel is rattling to weigh it down . Or, if its not a panel vibrating but two different pieces rubbing together, get some gasketing material or some weatherproofing stuff from your local hardware store and put it between the two pieces to keep them from rubbin' .

corvettecrazy wrote:

Sound deadening your hatch would seem a lot more productive and easier.

Close, but deadening isn't for these types of vibrations. You want an open celled acoustical foam. There are like 100 different products for it, but it should not be heavy, rather it should be like what Cooper mentioned, consistency of weather strips for your house.

You could probably just buy a roll of door weathering and just like the panels as needed for the desired effect, but this of course won't be as effective as sheet would be.

typically you dont see a downfiring subwoofer configuration in a car, thats more for home audio, just another style of bass production. My take on downfiring subs in a home is to create a less punchy, more felt type bass. Bass ingeneral is supposed to be omnidirectional and you arent supposed to know where its comming from, dowfiring seems to o this well. I prefer front firing in a home setting.

As for your situation, dynamat, secondskin, cascade sound deadening will be your friend. Tar paper and stuff found in home depot is heavy, adds a lot of weight and doesnt do a very good job. The goal is to find a product to help absorb the vibrations and turn it into heat energy, which is how the vibrations are dissipated. Put some of the sound deadener on the plastic and that will stop it from rattling.

SuBXeRo wrote:

typically you dont see a downfiring subwoofer configuration in a car, thats more for home audio, just another style of bass production. My take on downfiring subs in a home is to create a less punchy, more felt type bass. Bass ingeneral is supposed to be omnidirectional and you arent supposed to know where its comming from, dowfiring seems to o this well. I prefer front firing in a home setting.

Down firing has nothing to do with the bass being omnidirectional. The length of the low frequency sound waves is why it's omnidirectional. The wave lengths are so large in comparison to the distance between your ears that your brain can not triangulate the location.

Down firing subs in home audio is popular because it creates more bass. It increases the radiation impedance which in turn increases the efficiency (almost the same concept as placing a subwoofer in the corner). Generally, it creates more peaks because you are exciting the room modes more and they are louder than everything else. For the everyday person, they aren't looking for flat response from there subwoofer. They just want louder and the downfiring gives this to them.

There's no need to have a downfiring sub in a car because the wavelengths are HUGE in comparison to the inside of the vehicle. The size of the "room" is VERY small and the radiation impedance is already pretty high. There will be little to no gain from a downfiring sub.

i didnt say downfiring causes an omnidirectional bass.

SuBXeRo wrote:

Bass ingeneral is supposed to be omnidirectional and you arent supposed to know where its comming from, dowfiring seems to o this well.

Sounds to me like you said it plays some sort of roll.

SuBXeRo wrote:

As for your situation, dynamat, secondskin, cascade sound deadening will be your friend. Tar paper and stuff found in home depot is heavy, adds a lot of weight and doesnt do a very good job. The goal is to find a product to help absorb the vibrations and turn it into heat energy, which is how the vibrations are dissipated. Put some of the sound deadener on the plastic and that will stop it from rattling.

Once again, you don't want deadener, you want a dampener.