Featured Port size: manual vs online calculator. Big difference?

Lukasz S.

CarAudio.com Newbie
Built a small box for an 8" sub. Suppose to be ported but the port size in the manual suggests 3.5in 7in length for 52hrtz. Online calculators are very different. Which should I use?

Speaker 8in BOSS cxx8
300w rms 600w max
Ported Box cu ft: .53 as per manual
Manual states port size at 3.5in x7in length

Online calculator shows 3.5x 14in length for 52hrtz

box size is 20x8x9 using 9/16th mdf

Amp: using my old 600w Sony xplod 2ch/mono 250rms
 

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In both scenarios it is 3.5" round. Make it 14" long and shorten it if does not sound to your liking. If it is a new sub, let it break in before modifying that port length.
Good point, reason Im asking is my box is 8x9in with 20 in width if I do 7in I can have port on the front, if any longer, need to have port exit on the side as 14in would be to long given HxD. Wa
 
You can always use an elbow. BTW, what pipe are you using that is 3.5"?
I was going to look at what is available online (pvc or speaker ports)... geez not much for a 3.5in in that length...

Why would manufacturer suggest a port size you can't purchase a port for 😡

K going to have to see what a smaller port or split into 2 ports will be
 
Jmo but that cxx8 is probably going to disappoint, and when the manual recommends .53ft3 with 3.5" round tuned 52hz don't expect low-lows for sure. I'd probably just go with a 3" round at the same length myself. The smaller port area and slightly increased airspace may just tune a bit under 50hz. I'd side port it then make sure the port output is positioned in vehicle where it can load correctly.
 
Jmo but that cxx8 is probably going to disappoint, and when the manual recommends .53ft3 with 3.5" round tuned 52hz don't expect low-lows for sure. I'd probably just go with a 3" round at the same length myself. The smaller port area and slightly increased airspace may just tune a bit under 50hz. I'd side port it then make sure the port output is positioned in vehicle where it can load correctly.
Thx, ill look at the smaller ports. Yes I'm not expecting this 8in to rattle much just fill in some bass from the 6x8s and 6.25 door speakers (went with lower rms rating given no amp for speakers, think the kenwood 6x8s are 35w rms and pioneer 6.25 are 30 or 40) all on a 4x50w deck. Sounds super flat right now when you turn it up

Its going into the back of a c4 corvette. It was this or a bass tube but already had an amp and this combo is more powerful and cheaper vs the bass tubes. Both sub and amp are rated 600w, sub is 300w rms and amp bridged is 250w rms.
 
Can that sub be returned? I feel you can do better..

For example right now on clearance you can get a 10" Illusion audio sub for 59.99 and throw in .70 sealed box and it will out perform a 8" boss sub tuned to 52hz

 
Can that sub be returned? I feel you can do better..

For example right now on clearance you can get a 10" Illusion audio sub for 59.99 and throw in .70 sealed box and it will out perform a 8" boss sub tuned to 52hz

Those are supposed to be really nice subs
 
I've never heard them but have seen some talk about them. From what I gather not a great deal at the OG price of around 400.00 but at the closeout price it's a steal.

I thought about grabbing some for my spare ride.
I ain't heard either but the only bad thing I ever was the original price tag. If I had a use for full size 10 I wouldn't be scared to put out $50 bucks on one though 😂
 
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Lukasz S.

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