Port area

[hatedonmostly 5,000+ posts]

I'm about to build a new box, and I'm wondering about port area. I know the general rule is 12-16 cubes.

The box I'm designing has 15.5 sq. in. per cube. I figured that a larger port would be good because I listen to a lot of slowed music that will move more air, and this would reduce the chance of port noise.

After doing some research I've found that too much port area can be a bad thing. I've read that on the low notes, it will make my subs free air and loss of cone control is more likely, and that it will make my box more peaky.

I'm more of an SQ guy, and I don't want a huge peak or any excursion issues, as I listen to a lot of slowed music. Would 15.5 sq. in. per cube be too much, or would it be fine because it's not overly large?

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[fasfocus00 5,000+ posts]

I'm about to build a new box, and I'm wondering about port area. I know the general rule is 12-16 cubes.
The box I'm designing has 15.5 sq. in. per cube. I figured that a larger port would be good because I listen to a lot of slowed music that will move more air, and this would reduce the chance of port noise.

After doing some research I've found that too much port area can be a bad thing. I've read that on the low notes, it will make my subs free air and loss of cone control is more likely, and that it will make my box more peaky.

I'm more of an SQ guy, and I don't want a huge peak or any excursion issues, as I listen to a lot of slowed music. Would 15.5 sq. in. per cube be too much, or would it be fine because it's not overly large?

are you implying that slowed music increases dbz?

you should be fine.

 

[FIMPALASS 10+ year member]

What sub you running and how much power?

 

[hatedonmostly 5,000+ posts]

Two Sundown SA-12s in 3.5 cubes tuned to 33 with 1200 watts.

 

[RAM_Designs 5,000+ posts]

15.5in^2 per ft^3 is a little on the big side. The bigger the port the more quickly the response will drop off below tuning, and the bigger peak you'll have as well(obviously, because it'll be a larger radiating surface). Because of this I stick with ~12in^2 per ft^3 for my daily setups that I actually care about SQ with.

Now if I just want to have a loud groundpounder, tuning around 32-33hz with 15-16in^2 of port per ft^3 works great. But for daily I do upper 20's tune with ~12in^2 per ft^3. Granted, this is all sub dependent, and I pick subs that work well with the kind of tuning that I like, and that give me the response I'm looking for.