optimal "musical" port area for SP4?

[ncc74656]

what is the optimal squared port area for a SP4 18 assuming ill be running RMS to start with and perhaps a bit greater than RMS down the line so 3000-4000W ish. tuned to 33hz and wanting quality and volume to be balanced out. slot port

[DylanBunch]

Maybe 80-90 port area at 14 port per foot. Probably a good start

[ncc74656]

thanks for the input. ive had some suggestions at 150-167 and some as low as 80. it seems however the general thought is some where in the 80-100 square inch range so thats what ill run with for now and try to narrow that down.

how does the area per cubic foot play into the equation? i was told that the square area of the port is what really matters and that the cubic area per foot is a useless number.

[Nikitaaa]

I would do something like 12 per for a musical box

[scoobywrx05]

I see so many of these"how much port area" questions its funny. Allot of people use the so many sqin per cube method. It's a general measurement that works ok. But it's like saying a 18 inch sub with a 32mm xmax is gonna take the same port area as another 18 inch sub with a 19mm xmax in the same box tuned to the same frequency.

[Max1636]

I had my box designed by PWK Designs, I'd recommend him, takes the hassle out of designing it yourself and you know it will be right the first time and your getting the most out of the woofer.

[Joe X]

what is the optimal squared port area for a SP4 18 assuming ill be running RMS to start with and perhaps a bit greater than RMS down the line so 3000-4000W ish. tuned to 33hz and wanting quality and volume to be balanced out. slot port

You can't balance frequency response just by changing port area.

[ncc74656]

i understand that xmax and vas and other specs play into the port area required for the sub. I used a website that listed me needing a 167 minimum port area but it is using 70%BL to determine that, what ever that means. i have been told that i need to base my port area off of more than just that spec so im trying to determine exactly how to do that. perhaps the question i should ask is what would be an optimal velocity for the port air? this website asks for more specs so id assume its more accurate thant he first one i tried:

http://www.bitpusher.in/?p=portarea

if frequency response does not play into the port area why do people say my "musical" ability of the box will be crap if i have to much port? is that not effecting frequency?

[Emmet]

I had my box designed by PWK Designs, I'd recommend him, takes the hassle out of designing it yourself and you know it will be right the first time and your getting the most out of the woofer.

Just to add to that, I've heard more people say you shouldn't go to PWK than people say you should.

Apparently when his designs are not that great he just says it's because it's built for a flat response not peak output.

RAM designs on the other hand...

[ncc74656]

my last box i had designed and build by an expert and it did not turn out great. this time round im going to be building it myself and making sure i know exactly whats going on with the box before i do anything so that i know what im getting. the further i go through life the less i trust anyone else to do anything for me.

im playing with WinISD right now and not getting much of any kind of result as far as graphs go. i must be doing something wrong but im following the tutorials to the letter.