2Slot Port question

[sqlfreak]

Can I use 2slot ports instead of 1slot port?
check it out..

instead of 1 port of 15x4 and 40inch of effective port length, could i do 2 15x2 each side of the box with 20inch of effective port lentgh EACH!?
will it have the same effect as 1slot port?, its for 3.8cu.ft NET(w/sub in the box, for a 15") and want to tune @30hz

[envisionelec]

> Can I use 2slot ports instead of 1slot port?
> check it out..

> instead of 1 port of 15x4 and 40inch of
> effective port length, could i do 2 15x2
> each side of the box with 20inch of
> effective port lentgh EACH!?
> will it have the same effect as 1slot port?,
> its for 3.8cu.ft NET(w/sub in the box, for a
> 15") and want to tune @30hz

Yes, you can do that. They each have to be as long as one, though.

[sqlfreak]

> Yes, you can do that. They each have to be
> as long as one, though.

that means each 15x2 have to be 40inch long or 20inch?

is there a difference with the sound reproduction with a 2slot port?

thx alot for the quick response

[davidyohn]

> Can I use 2slot ports instead of 1slot port?
> check it out..

> instead of 1 port of 15x4 and 40inch of
> effective port length, could i do 2 15x2
> each side of the box with 20inch of
> effective port lentgh EACH!?
> will it have the same effect as 1slot port?,
> its for 3.8cu.ft NET(w/sub in the box, for a
> 15") and want to tune @30hz

1 port 15X4 @ 40 inches = 2 ports 15X2 @ 40 inches. Approx. same tuning would be possible with 1 port 15X2 @ 20 inches, but with more port noise. (Actually, your lengths are too long according to my math. For 30Hz in 3.8 cuft, I get single port results of 15X4 @ 35.4 inches, or 15X2 @ 11.6 inches.

[envisionelec]

> that means each 15x2 have to be 40inch long
> or 20inch?

> is there a difference with the sound
> reproduction with a 2slot port?

> thx alot for the quick response

They each have to be as long as one. What does that tell you?

One is 40" long, right? So two are 40" long EACH.

You're almost as bad as my wife!

It can affect sound quality certain frequencies, but if you keep them symmetrical around the woofer (one on each side, for instance), then it can only sound better. Try to keep the mouth of each of the ports at least 2" away from the woofer face.

[sqlfreak]

> They each have to be as long as one. What
> does that tell you?

> One is 40" long, right? So two are
> 40" long EACH.

> You're almost as bad as my wife!

> It can affect sound quality certain
> frequencies, but if you keep them
> symmetrical around the woofer (one on each
> side, for instance), then it can only sound
> better. Try to keep the mouth of each of the
> ports at least 2" away from the woofer
> face.

but, i dont get it, should'nt it be 40inch each if u add another port of 15x4..?

[sqlfreak]

> but, i dont get it, should'nt it be 40inch
> each if u add another port of 15x4..?

its just ridiculously too long 40inch x2 ..80inch of port length total @ 15x2?? U really sure about that?

[davidyohn]

> its just ridiculously too long 40inch x2
> ..80inch of port length total @ 15x2?? U
> really sure about that?

Yes, that is correct.

[envisionelec]

> its just ridiculously too long 40inch x2
> ..80inch of port length total @ 15x2?? U
> really sure about that?

No.

Two Ports:
Port 1: 15"x2"x40"
Port 2: 15"x2"x40"

One Port:
Port 1: 15"x4"x40"

Clear yet?

[rudyjakubin]

> 1 port 15X4 @ 40 inches = 2 ports 15X2 @ 40
> inches. Approx. same tuning would be
> possible with 1 port 15X2 @ 20 inches, but
> with more port noise. (Actually, your
> lengths are too long according to my math.
> For 30Hz in 3.8 cuft, I get single port
> results of 15X4 @ 35.4 inches, or 15X2 @
> 11.6 inches.

Same as above, but on my speaker instead of a 6 x 6 inch square port I cut in half. Two triangles - one on each side of the box.
Looks neat.
Use WinIsd, great program for doing this;
<A HREF="http://www.linearteam.dk/default.aspx?pageid=winisd">http://www.linearteam.dk/default.aspx?pageid=winisd</A>