Port Q that will stump the pros *PICS*

[j3bus2k3 5,000+ posts]

Just like your screenname entails...your as crazy, and dumb as mickey rooney...

 

[PowerNaudio 10+ year member]

both enclosure will work the same exact way, the last enclosure you posted will have a lower tuning freq because of the increase Vb. why dont you just build the port to go the full hight of the enclosure?

 

[mokedaddy 5,000+ posts]

To answer your question, yes it will change the airflow. The real question is how much and if it would be worth it to have to make the box that much larger to account for the 'spacers' and my guess would say prolly not. But only testing will tell you for sure. But one thing proven over and over is that you will usually be louder in a common chambered box with one large port.

 

[rooneypower 10+ year member]

so that means put the spacers in the box. Why i said it will look cool is cause in about 10 mins i will be completly done with the plans and you can see why i put the ports in the middle

 

[Blove1991 10+ year member]

If your about looks then build it and be happy with the sound and dont worry bout extra space.....if you want sound build a full lenth port.....

 

[mrray13 10+ year member]

IME, it wouldn't be a noticeable difference with the dead air spacers or not. someone mentioned it earlier, build it the wat that gives the proper airspace/tuning, and run with it. i wouldn;t go through the trouble of blocking in the "dead space" . a mic might tell the difference, but i seriously doubt you will.

wheeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee //content.invisioncic.com/y282845/emoticons/peace.gif.2db28b618ed8d1964ebbe2f5021d2c39.gif

 

[expo5.0 10+ year member]

i don't see it making any difference-

 

[PV Audio 5,000+ posts]

Looking sick and being functional usually don't go hand in hand. Go with what jizmface said and just make it a full height single port.

 

[W8 a minute 10+ year member]

IMHO single ports offset to one side with 2 subs looks like buttcrack. I understand that sharing one chamber "couples" the subs output to some degree but I'm not willing to sacrifice the look of the finished product for that small amount of gain. Every time I see a vehicle like that it looks like someone threw some old prosound/DJ equipment in their trunk and called it a day. Again, just my opinion and it probably doesn't mean jack to anyone else. LOL

 

[rooneypower 10+ year member]

W8 a minute.....

Its 1 PORT for each sub. There is a piece of 3/4" birch wood(using birch ply) seperating both ports.

Im not that dumb to make one port.....

This is why i am putting them in the center of the box...This is wut im gonna build. Just finished the details of the box. I think it looks pritty cool.//content.invisioncic.com/y282845/emoticons/eek.gif.771b7a90cf45cabdc554ff1121c21c4a.gif

A flared port w/ two 3/4" birch boards on the front

 

[Trixter 10+ year member]

i think powernaudio hit it on the head. it will just be easier to build the one without the spacers...dead air...or whatever you call it. as long as the volume is the same in both plans, and the port area and length, then they will sound the same.

still how did you get 1050 for the sq"????? they don't look 42" tall...

 

[helotaxi 5,000+ posts]

There's no "dead air" unless you have it significantly blocked off from the rest of the air in the enclosure. Unless your port is too small area wise there shouldn't be a ton of air "flowing" through the port. It is a transfer of pressure not a conduit for the transfer of air. With a setup that has no port noise the air velocity in the port is usually low enough that air at the inner port opening does not have the time during a half cycle to make it to the outer port opening. Thus he port output is nothing more than a pressure wave traveling down the port. The air volume in the box determines the pressure required to get the port pressurized and the air above and below the port in your design is just as much a contributor to the volume/tuning and any other air in the enclosure.

 

[singlefordrange 10+ year member]

go with the plan that doesn't have bracing under the port which causes your "dead air space" or air space not being used...get a little bit more volume...it should make your tuning go up slightly though....if i am not mistaken...

 

[rooneypower 10+ year member]

ok i guess ill go with the regular port and no spacer above and below the port.

Some people asked how i got the #'s for the port area.

Well if i am right(i think i am) you take your port w=3" H=12.5" D=28"

So 3 X 12.5 X 28= 1050"

Correct???

 

[rpfuror 10+ year member]

Here are a couple answers.

You statement above is incorrect.. you just calculate the H x W, which gives you 37.5 sq/in.

I agree with what PV Audio said (can't believe I'm saying that //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif)

To look cool you’re going to sacrifice something. In this case you are going to add unnecessary turbulence into the design.

You also stated “Im not that dumb to make one port.....”, there is absolutely nothing wrong with making one port for the entire box as long as the design is good.