http://www.v6performance.net/forums/...564&forumid=20

All you're doing is canceling out the rear soundwaves from the drivers. If you have a properly setup system, you can harness the sound coming out of there. That'* how Bass reflex (ported) systems work.

Its just an idea for those who plan on keeping their stock systems and want better SQ

mind I ask if most of us have bose an bose has been doing similar thing whats the difference? :?

With the doors it should help a lot definetly, but it'* just egg crate. Buy one of those eggcrate bed pad thingy'* and cut it up. Cheaper, more etc.

I think this will help with sound, and dynamat will help with sound (not as well, but good) and outside noise.

Ported boxes don't harness the sound coming from the back of the speaker. They sorta do, but theres a different reason for porting.

You don't actually want to hear the sound coming from the back of the speaker. It is a complete opposite to foward firing sound. They will cancel each other out. Thats how those noise canceling headphones work.

Theres 2 basic types of cabinets: Sealed, and Ported

When you have a sealed cabinet and the speaker is not moving there is equal pressure on each side of the cone. But when the speaker moves out there is less preasure behind, and when it returns to normal position there will be a slow breaking effect. This helps reduce distortion in the cone. The speakers simply don't hit as hard.

Now on a Ported cab, the preasure pretty much stays the same if it'* ported right. Different size ports tune the cab slightly giving the speaker different preasure which changes the outcoming sound. If the speaker isnt tuned right when you get a certain distance away you won't hear the note, it'll be mush.

But the big factor in porting is that the speakers move quicker. You'll have faster speakers (good for when you're using big cones) but the only draw back is that they are easier to distort.

They probably got better midrange because the bass resonance from the door is less apparent, bringing out the mids.

ill have to agree with bonnemn on this one, that is precisely why ported boxes get louder but sound like crap out of their tuning freaquency. The back wave does reinforce the front wave in a ported box. When u tune a ported box, u have to time it the backwave to reinforce it at just the right time. What tuning freaquency u want it at determines box size and port length and therefore time. When the air moving from the speaker is in phase with the air moving out of the port u get the optimum sound that it was tuned to. the more u move away from this freaquency the less the 2 sound waves reinforce each other and the more they cancel each other out. as far as a ported box making a speaker move quicker, that is false as well. the resistance of the air in a ported box acts like a spring and makes the speakers move quicker. It also increases power handling because it takes more to move the speaker with less compliant air behind it, however it also decreases sensitivity for obvious reasons

Ported boxes harness the rear sound from a speaker! The proper use of them, and tuning is done with the port length and diameter mainly. If those are correct, it will make the out of phase rear signal, in phase with the front.

Not exactly.

There is less resistance in a ported box than a sealed. The sealed box actually has the spring effect. The preasure is always trying to equalize itself, trying to keep the speaker at center position. So it'* slowing down the action of the speaker, there is a braking effect.

The ported box on the other hand, keeps equal preasure on both sides. When the voice coil moves it has less resistance, therefore moving quicker.

It'* the equivalent of running foward, then running foward with a bungie cord hooked to a tree and you're belt.

Power handling is always dependant on the speaker itself not the cabinet. Voice coils have a certain Resistance and wattage rating. The wattage rating is how much a particular voice coil can work at a concasnt heat. If it can't disapate that heat quick enough, the coil will burn up.

The ported speaker is louder because it does not have extra outside forces acting on the cone. It can simply move more air.

If i took 300 Watt 15 inch speaker and hooked it up to my 300 watt bass amp. Put it in a sealed box, then put it in a ported box. The porting will be louder, but i couldn't put a bigger amp on the speaker. It would burn up the voice coil.

If you don't believe the ported box being faster than a sealed, you can come listen to my bass Rig. I have both kind of cabinets. One that has 8x10'* and one that is a 12 and a 15.
The 8x10 is like 4 2x10'* stacked on top of each other. Each pair is in its own sealed capinet. The 12 and 15 on the other hand share the cabinet and it'* ported.

Even though the 12 and 15 speakers are bigger than the 10'*. The 12 and 15 cab is a quicker responding cab than the 8x10. Though, the 12 15 cab will start to distort earlier than the 8x10.

The 12 15 cab isnt a POS either. It was designed by the guy that made the loud speakers at the Jurrassic Park ride. You're hearing his speakers when you hear the T-Rex walking.

ok let me correct myself here. i meant that the sealed box acts like a spring and can make the speaker move quicker i can see the bs flags already i know. when i typed that respones it was when i had just woken up so it didnt come out sounding like i wanted it to. And a smaller box can increase the power handling of the speaker'* suspension, but ur right the voice coil itself woud be unaffected, besides the heat buildup.