Where to place ports?

[mazeroth]

Got the panels all cut for my line arrays. Using 10 Dayton RS 5" drivers per side, with 5 per section. Going with a single 2.875" port per section but was wondering where the best place to put the port would be? Each section is 21" in height, with 5.5" internal width and 9.5" internal depth. Should I put the port dead in the center, or at one end? I have no clue

Also, how much polyfil would you put in each section, or do you think I should go with some kind of foam? I'm building these on a tight budget so please keep that in mind.

Thanks a million!

[mazeroth]

Just so you guys can see what I'm doing here's a picture I took before finishing the cuts. This shows you, roughly, the size the speakers will be. Middle of the ribbon will be at 40" height, and there will be an 8" compartment at the bottom where the binding posts will be along with the passive x-over. That panel will come off, but the rest will be glued on. Total height = 72 inches. After hearing Dr. Griffin's Needles at the Dayton DiY event in October I had to have a set of line arrays like his. Thought I'd try to design my own

[paulspencer]

Place your port so that they won't space the drivers further apart ie. at the rear (with suitable clearance) or at the bottom. It's not that critical. Make sure they aren't too small so that they have ideally <17m/s velocity in the vent or <34m/s as an absolute max when driven to their limits. Flares also help. It's not just about chuffing, but also about port compression, and getting the best possible performance.

[mazeroth]

WinISD shows a 0.10 port velocity with the ports I'm using. I've read in the past that WinISD isn't super accurate when it comes to port sizes. Do you guys know another program that's easy to use that gives better port sizes?

As far as port placement, they are going on the rear. I just wasn't sure if it was good to place it in the center or if it was good to put the port as far away as I could, as I've seen done in many speakers.

Thanks!