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hey guys, i'm getting ready to build a ported box for my sub and trying to make a false floor, does it matter where the port is in the box? i was thinking of having the sub in the same place it is now, but make the new box deeper, and have the port firing towards the front of the car.
here's a pic of what i have now

now, i'm thinking of the port being about in between where the amps are now, but firing out of the side of the box that will be facing the front of the car, if that makes sense. will thnat affect the sound or does the port need to be in a certain place on the box?

 
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port placement won't affect the sound of the box, port SIZE will.

 
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You'll want the port facing the same direction as the speaker.

The reason for this is a lot of math involved with waves cancelling, being out of phase, etc. Ideally you want the sound waves from the port to reinforce the sound waves from the speaker--that is to say they're in phase (giving you +3db at the tuned freq of the port).

There's a couple of crazy audiophile sites I've found that discuss this stuff in extreme detail...I'll see if I can't link some later on.

 
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No offense, but until you prove what your saying i believe mega, he's never been wrong.

 
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What he's saying makes sense, listen to him

 
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while that is true the 3db gain is only at the tuning frequency of the port which is usually very low since you dont want the speaker reproducing sound lower than the tuning freq. When a speaker in a ported box produces sound below the tuning frequency the box unloads and the sub behaves as its in a sealed box with a big hole.


Certain box designs specifically have the port on the opposite side of the speaker, it doesnt really make that much of a difference

 
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Yes. Optimally you're supposed to run a filter 10Hz below the port tune freq so that the sub isn't trying to reproduce those freqs...

Ah, the joys of sub building...

 
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thanks for the responses guys but i ended up abandoning the ported box, I cut the peices and set them into my trunk to see how much room i'd have and realized i would have a trunk anymore, i'd go from storing about 10-15 dead hookers in my trunk to like 3-4 max. I can't deal with that small of trunk, so i ended up building a 1.256ft^3 sealed box for it, it sounds soooooo much better than my old false floor, and is much more sealed too. I thought my old one was sealed, but this one when i push on the woofer, it wont move. I love it, now i just need to carpet, secure the box, and put my spare back in....I'm at work (on break) and on my lunch I'll go out to my car and get pics.

 
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looking forward to seeing the pics, good thing about the "storage" situation

 
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yea, i tried to take pics but it was too dark and my camera sucks almost as much as the hookers, so i'll try and take some tomorrow, or just wait til i get it carpeted and such

 
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well, you know that thread about the stupidest thing you've ever done? Yea wish i could find it...long story short,
Drinking+crappy carpet(that i could find the screw holes through and stripped out all the holes)+slippery screwdriver=ruined box and a puntured sub i am so pissed and was last nigth so i drank more. good news is i bought a Kappa Perfect 12 and I'm going to build a ported enclosure for that one cuz i have about a week to plan and design it all...bring me to my next question, I have a 800w Pioneer amp, that should be plenty to power that sub right?

 
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that sucks man. Drinking and tools never end well.

that amp should be fine.

 
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next question (I'm completely redoing everything in my trunk), does the box depth matter? as long as it's the correct volume the depth doesn't matter does it? BTW iI'm giving it 1 inch between the back of the woofer andf the back of the box.

 
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nah depth doesnt really matter, as long as the speaker fits in and seals it'll be fine.

 
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you do indeed want to give the woofer's pole vent some space so it can cool. Remember, even the most efficient woofers in the world never achieve 10% efficiency, so of the 800 watts you send a woofer, at least 750 go directly to heat...

Side Note:

thats just funny to me.... not an insult to you mr hurtz, its just funny to leave for a year and come back to this =)

 
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would be great if a normal speaker ever came close to 10% efficency, you'd think someone out there would have managed to figure it out by now.

 
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ever hear of a woofer called the phoenix gold cyclone?

they used servo motors to move a fan like thing to create the same effect. that guy there reached 10% efficiency, but it was limited to 50 hz

now to figure ou something that can do that at 3 khz

 
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i saw a demo of that while i was at mobile dynamics, talk about weird