Bass sound windows up/down

rats no edit...I ment to put that the volume is .75 per side as each sub has it's own chamber.

I get the same thing. i have build many different size boxes, ported sealed. it comes down to frequency waves. when your window is up the waves are bouncing of your windsheild and the drop is canceling new waves a bit. but when the windows are open the waves are free and clear to escape they are not trapped. so there is no cancelation and you decrease the pressure that the subs create in the cabin by opening the windows so with windows up you are allowing a free and clear path for sound to travel instead of being bounced off your windsheild traveling in the opposite direction as new sound waves are traveling canceling out certain levels. and such.Jon

Installer/Help Technician

---coral springs florida---

mecp certification is not always needed. I have it and it has not helped me out at all. my experience out shines it.

Hey thanks for the quick reply! So is there anything that can be done about this? I've heard/seen this before but never to this extreem. I can literally hear and feel like I just upped the power by about 2-3 times more when I open the door as opposed to just windows down or especially windows up.

I can't guarantee this will help but you could try positioning/facing your sub different ways to see if it helps with the cancelling.

From my experience it differs from vehicle to vehicle. This "anomly" you are describing most often occurs in SUVs and Hatchbacks where there is no trunk wall to block the waves. I personally dont notice a huge difference when I roll down the windows in my sedan.

Thanks for the replies guys. The vehicle in question is a 68 VW Beetle. They are in the package tray ( in the back below the rear window) firing forward. The way I designed the box (quick throw together) they can't fire down. I MIGHT be able to turn it to fire them up or face them to the rear. I might try that and see how much of a differance it makes. I was just wondering if the volume inside would make a differance as far as window up or down.