Does Port Diameter Matter?

[Jonahdude 10+ year member]

Say you have identical boxes, one with a 2" port at the proper length to tune to 35hz and another with a 4" port tuned to 35hz. Would either box offer more SPL?

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[tRiGgEr 5,000+ posts]

No - just less port noise and resistance which could result in a little increase in spl but not noticable.

 

[Jonahdude 10+ year member]

So I might as well go with a single 2" diameter port that's 1.5" long, to tune to 35hz? That just doesn't seem right for some reason, I always see people use bigger ports. 2.35 net internal volume, I used this calculator:

http://www.the12volt.com/caraudio/boxcalcs.asp

 

[tRiGgEr 5,000+ posts]

So I might as well go with a single 2" diameter port that's 1.5" long, to tune to 35hz? That just doesn't seem right for some reason, I always see people use bigger ports. 2.35 net internal volume, I used this calculator:
http://www.the12volt.com/caraudio/boxcalcs.asp

No. What is the size of your box, after speaker displacement. What speaker are you running, What kind of power will you be running.

 

[Jonahdude 10+ year member]

I'm building two indentical boxes, one on each side of the trunk. After displacement, the volume is 2.35 ft^3 each box. I haven't built the boxes yet, but that's the plan. External dimensions are going to be 13x13x35. I'm running 3 MTX Terminator 8" subs in each box, and they're going to get around 100w RMS each.

 

[tRiGgEr 5,000+ posts]

A port 11.5 x 2 x 18.5 would work with that box. tuned around 35hz

 

[Jonahdude 10+ year member]

How would I make it?

 

[tRiGgEr 5,000+ posts]

How would I make it?

With wood??????????????????????????????????

Ok your going to use one side of the box as a side of the port. Just build the port on the side. Have it bend in to the box at the corner. And keep the port area constant all the way threw.

 

[Jonahdude 10+ year member]

I can't picture what it is you're talking about... do you have a picture of something similiar?

 

[Jonahdude 10+ year member]

bumped ttt

 

[BASS OUTLAW 10+ year member]

well i didnt challenge in an SPL comp b4 , but i ve seen many SPL ports, it always got larger area.

 

[Jonahdude 10+ year member]

Well I'm not really trying to make an SPL box, I know I asked which one would have more SPL but I actually want more SQ than SPL.

 

[Jonahdude 10+ year member]

I want it to have more SPL than a sealed box, but not lose sound quality, if that's possible.

 

[jemorgan85 10+ year member]

No - just less port noise and resistance which could result in a little increase in spl but not noticable.

So you are telling us that less effective port radiating area would not be a big deal.....?

You ever competed before?

 

[DBfan187 5,000+ posts]

So you are telling us that less effective port radiating area would not be a big deal.....?
You ever competed before?

damn, you beat me!//content.invisioncic.com/y282845/emoticons/up2something.gif.dd110ecf3ae4b76050d87598f2f8de7c.gif
more port area=louder resulting in longer lengths in ports.