Little help with port length
 

So I've been working out a design for a Sundown NS-12.
Anywho, I'm looking at doing 1.75ft^3 @ 36Hz.
I've worked out having that a 3"x14.5" port area I need a length of 45.82"
WTF, seriously?
I have more volume in the port than the enclosure
Do I have this right? or am I doing something wrong?

I don't usually make "smaller boxes" for single drivers.

Thanks

It's due to the LARGE port area/low tuning ratio. Having almost 25"sq of port area per 1cu ft is alot, combined with the low tuning frequency. I actually got a lil over 46" but yep, thats what your looking at.

It would decrease drastically if you went with a 14.5 x 2.25" port. Then your only looking at about 34" long for 36hz. That will still give you about 18.6" of port area per cube. :dunno: 32.625"sq for 1.75cubes.

It's up to you. :smilie_da

A smaller box with a large port and low tuning will be longer then on a larger box. Its not to big though, i have 100 sq.in. of port for 2.6 cubes.

True, but your likely tuned much higher. Or have a pretty large enclosure. I don't have a problem with that much port area, actually I wish I could go bigger. Something about the feeling of air moving past you... mmmm I was just giving him an option to get what he wants just in a smaller package seeing as he was a little set back by the extra area the port was going to use. If he wanted to shorten the port length he'd have to go with a smaller port area, or a larger enclosure.

No my box is tuned at 36 hz, but it is a very large enclosure. Its just under 6 cu.ft gross. But i do agree with you, If SS went with smaller port area he could still keep his box small with not having to put so much port. What r your goals with this sub? Sound SPL both? Have you thought of using aeroports?

Thanks guys.
I'm looking for something that will do well with music, yet get me 140+.
I know its possible, I've done it before different sub and amp.
But I was kind of shocked with the extra length of the port.
I have thought of aeroports, but I'll need to bend it (them)
The box is going to be rather shallow, i need to conserve some space for my
little man's stuff.

you need more cubic footage.
and are you planning on using a slot port or aero port

How much more do you think I'll need?
And either or really doesn't matter. Both will end up needing to be bent.

2 cubic feet after all displacements.

3" aeroport and a 3" wide slot port are two different things

Well i know sundown says they like small boxes for the 12s. 1.5 after displacements. I have seen big numbers in real small boxes with those subs, but lots of power how much power are you using?