Port length... just curious... question first: How critical is the port length when dealing with a 5.25 cubic foot box for a Dayton 15" HO driver?
I was doing a little playing today in WinISD and concluded that port length isn't as critical as I thought.
For example: I'm not sure EXACTLY what my box dimensions are because I put in a lot of miscellaneous bracing and estimated the equivalent volume that the speaker itself is displacing at about 1/2 a cubic foot. So if I ESTIMATE a volume of 5.4 cubes, and look at the port length, it goes down to a minimum port length of like 24" depending on where I tune. At 5 cubic feet, it goes up to a maximum port length of about 32" depending on where I tune. Assuming I'm around 5.25 cubic feet of air space, the transfer function magnitude, rear port air velocity, and port gain look reasonable at anywhere from 26"-30" long. Shorter actually looks a little better on the transfer function but worse on port air velocity.
So am I correct that an inch or two difference in port length isn't going to make much of a difference in the sound of the sub? Which is more important, keeping the port velocity as low as possible (reducing port gain) or keeping the transfer function magnitude looking good?
Thanks in advance!!!!