Cause of "moving air"

[zerosktr111 1]

So, what is the cause of "moving air"? There are two possibilities in my mind that I think would create this. #1. Air Displacement from the motion of the moving cone of the subwoofer. #2. Actual pressure (sound waves) moving the air inside of the car.

In scenario #1 the key to moving the most air would be to have the most cone area, the most excursion of the subwoofers and to have a sealed box (ports have an opening in them so technically a port would help the equalization of air pressure inside of the car) This would also explain why Randy Kubek pretty much has a mobile wind tunnel because he has always ran sealed boxes. (

for reference) In scenario#2, there is much less needed strategy to move air because all you need is a certain DB level at a very low frequency. The main thing you would need to do is get a huge LOW tuned ported box and let the hairtricks begin.

Sorry if I have come off really dumb but I am new to car audio and I was just wondering what the true cause of moving air was.

[Adrian_D 520]

You move air by....displacing it.

Comparing a sealed box to a ported box, the excursion will be greated above the tuning of the ported box for the same power level.

So for ultimate in hair tricks, lots of cone area and sealed boxes is what I would do.

[bassahaulic 155]

Sealed boxes are best for hair tricks? I am now in deep confusion and need to sleep this off.

[SpeakerBoy 64]

i Thought that the reason ported boxes moved more (h)air, is because in calculating the enclosure and all that jazz (in a comp vehicle) you build the box to make the front wave, and the back wave hit, at a certain point, at the same time. Am i right?

Edited November 5, 2009 by DeepSubBoy

[mjmarovi 8]

well I was just finishing my longer detailed explanation, but now i'm pissed cause my laptop decided to go back a page, therefore losing everything i just typed.

maybe I will re-post at another time, but right now I am far too f****** pissed to do it.

anyway air movement is caused by the difference in air pressure. sure cone movement and displacement can make a big difference here, but if that was the sole reasoning then a 15" cheap sub on 500 watts with 40 mm of xmax would move more air than a Fi BTL 15 with 28mm of xmax. same size woofer making larger movement would displace more air, but it doesn't create nearly the same pressure.

this is also the reasoning for why there isn't much air movement when vehicle is all sealed up, because the pressure is constant.

[TheSundownFire 0]

So basically youre saying that since the air in the rear is pressurized it moves to areas of low pressure ie the doors or windows because that is what the tendency of gases and fluids is?