Dukk

Dude, you seriously need to forget the 16sqin per cuft thing and stick to designing a box based on the TS parameters and not coincidence.

Lord Huggington

iTrader: (1)

Why doesn't Fi recommend based on TS?

Does it not mean that for any air space 145.x is recommended, and that's just the minimum? 24" per for 6 cubes just seems like too much.

I want the best performance from this, and all I have to go by are Fi's recommendations.

Does minimum area mean that to get all the x-max out of it, it has to be that?

veeman

iTrader: (3)

here's an one i did on winisd using fi t/s specs and your dimensions. As it turns out the port area is right at 16 inches square/net cubic feet. Box is 38 x 20.5 x 29.5, port is 18.5 x 6.5 x 30.5 using 1' mdf, and below 20m/s velocity at 2000 watts(technically you should be below 17 m/s, but 20 has worked flawlessly for me so far), at 17m/s the port would have to be 18.5 x 8.0 x 38.5 for the same tune and Vb (makes port area 19-20 inches cubed/ft cubed which is technically below 5% of the speed of sound). The front baffle is 2" thick, and it's tuned to 33 hz. Net Vb is 7.5 cubes. Here are the charts for spl, group delay, excursion and port velocity at 2000 watts:

Lord Huggington

iTrader: (1)

These must require huge boxes...

With a port 8 x 18.5, the tune needs to be 34.46 hz to be at the minimum area.

34.46 hz with a 20" port length requires 11.18 cubes.

Lord Huggington

iTrader: (1)

Thanks. I was told to not go over 20" port length and I was going to use 29", so I had to make the box huge for the same tune.

Carstereos calculator says for 33hz the minimum vent area needs to be 141.73"..... so what's 120.25 going to do?

veeman

iTrader: (3)

yep, unfortunately, there are always compromises...especially in a vehicle. Anyway, looks like you're design will be solid regardless of the compromise, so i wouldn't get too bogged down with over thinking it.