Phoenix Gold Phorum

i've tried it all...
wired the sub out of phase, placed it at at opossite direction so it fires towards the cabin , removed the back seats so the sub fires directly into the passenger cabin, tried reversing the wires again and whatever crossed my mind so far...

but still the bass is much stronger with the doors open or windows downs..
but definitely heavier with the doors open and thats only the driver side ..

why is this guys and is there any way we can fix this ?

Bass performance is stronger the further it travels. Hence the reason most (not all) people aim subs away from the cabin. I believe you are experiencing the same effect. With the door closed the bass has less room to travel. open= more room travel.

my guess would be less wave cancellation

^ +1

i get it now...the open space allows the bass signals to fully develop by travelling further.

cancellation ? guys pls explain..
cancellation because of reflection ?

no more windows up during " bass " sessions...

its due to phase shift due to reflections in the car and also due to
dynamic compression* your compressing the air in your car at different levels and will effect the over all sound. compressing the cabin pressure will have effects on the bass waves in the car and effect the phasing combined with reflections can cause deterioation of sound.

when you roll down the windows it allows the bass to exit the cabin and
relieve some of that compression, also it relieves some of the reflections
on the lower bass.

if you wanna get crazy play with all your windows and see where you can leave them to still get low bass inside, yet keep them most of the way up.

brenzbmr@sb wrote:its due to phase shift due to reflections in the car and also due to
dynamic compression* your compressing the air in your car at different levels and will effect the over all sound. compressing the cabin pressure will have effects on the bass waves in the car and effect the phasing combined with reflections can cause deterioation of sound.

when you roll down the windows it allows the bass to exit the cabin and
relieve some of that compression, also it relieves some of the reflections
on the lower bass.

if you wanna get crazy play with all your windows and see where you can leave them to still get low bass inside, yet keep them most of the way up.

spoken by a true pro

I once heard it was due to Boyles law. So lets all get out our chemistry books class!

Boyles law states PV=K (pressure, volume, constant). Boyle's law is commonly used to predict the result of introducing a change in volume and pressure only. The equation is then changed to (Pafter)(Vafter)=(Pbefore)(Vbefore). With windows closed, your pressure are in the the loaded box and the cabin. When you open the windows, now your pressures are the cabin and the outside world. This change in volume creates the pressures to fluctuate slightly.

Its like going from a ported box to a sealed box. Except you are sitting in the port.

i would say your cab acts like a bandpass enclosure.^^^^^^^^

have you ever wondered why sometimes some cars drive pass your house and it like booming and then it get close and or they stop to say hi and it sounds like utter garbage..

then when they leave it starts booming again...

this is for all of you to figure out....im gonna play with you all today.

lets see the answers.

bdubs767 wrote:

brenzbmr@sb wrote:its due to phase shift due to reflections in the car and also due to
dynamic compression* your compressing the air in your car at different levels and will effect the over all sound. compressing the cabin pressure will have effects on the bass waves in the car and effect the phasing combined with reflections can cause deterioation of sound.

when you roll down the windows it allows the bass to exit the cabin and
relieve some of that compression, also it relieves some of the reflections
on the lower bass.

if you wanna get crazy play with all your windows and see where you can leave them to still get low bass inside, yet keep them most of the way up.

spoken by a true pro

nah, according to all the shops around here im not one, im a hasbeen


so no im not a pro, i just play one on tv.............

Resinate freq of the vehicle has some to do w/it as well.