turbo_flipper

I'm about to pruchase a sub, box and amp, and I'm thinking about going with a prefab box. I've seen boxes that look like they're designed for the sub to be firing towards the rear seats and other boxes designed so that the sub is firing towards the back of the trunk. Do I need to take this into consideration, or will the sub sound equally strong and accurate with the sub firing towards the back or twoards the seats. Thanks

Ne0h

Alright here's my take on all of that, I've heard people debate both sides of it but here's my 2 cents.

Sound waves have certain wavelengths at certain frequencies. Anywho the distance that a sound appears "loudest" is proportionate to its frequency. Basically the higher the frequency, the closer the distance to the source it achieves it's "loudest" sound.

Magic formula is:
Speed of Sound / frequency = Distance of Wavelength.

With this in mind, lets say you tune the box to like 50hz. 1125ft/s / 50 dictates that a 50hz waveform has a 22.5 ft wavelength. That means for the sound to appear at its "loudest", you need to be 22.5 ft away from it.

Now onto firing position of the box, if the box is tuned to 50hz...and facing backwards...that means the sound has MORE distance to travel before hitting you (aka reflect off of trunk etc etc). Which MAKES it sound louder. You fire it into the cabin, it has less distance to travel, making it softer. BTW, some of the sound intensity will be lost as resistance off of the trunk panels, etc etc..

An 80hz waveform has a 14.0625ft wavelength...ever measure about how far it is from your trunk to your drivers seat? =).

In short, how you fire it depends on what frequency the box is tuned at, and the distance it is away from from listener.

...I always hated physics...

Hope that helps...

jbenedict

... while I totally agree with Ne0h's comments, the question remains: sq or spl?

Firing the sub towards the back will result in greater spl, as will firing it up at the back window ( a +3db gain ), but so will having a ported box vs sealed

Firing a sub towards the back seat will result in better sq. Having a sealed box will also benefit sq.

Merkin

just get a sealed and point it to the rear

turbo_flipper

I'm going for sound quality, but I still want to hear the bass...if I go for a high quality 12" sub firing in a sealed box toward the cabin, will that give me enough volume to go with the stock non-bose system in my 2002 A4? Thanks again

jbenedict

I can see your stock system having trouble keeping up with the sub