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jbl_marshall21
08-01-2003, 05:45 PM
ok guys decided just to have one port. 4 inch pvc tuned to 25 hz. 6.33^ft3 before sub displacement. i don't know how much that would be. i just assumed it would make it 6^ft3. so 4x9 is what i came up with. max wattage to each sub would be 380 watts. do u think port noise would be a problem?

ShaunMac
08-01-2003, 06:03 PM
For a ~6 cu ft. box with one 4" round port

I keep getting this:
9" long would tune around 22Hz
6" long would be around 25Hz

Could do two 4" ports at 15" long for 25Hz tuning.
This gives you twice the port area = less chance of noise.

What sub are you using and how many?

jbl_marshall21
08-01-2003, 06:30 PM
2 the 2 pioneers in my sig.

ShaunMac
08-01-2003, 06:43 PM
You might be alright with one 4" port.

Two 4" is a safe bet for less port noise.

How about one 6" round port that's 16" long for 25Hz tuning.
6" port will give you a lot more area than a 4" port.