based on dimensions, we're talking 69L with port dimensions of 2.6in wide, 15in tall, 14.5in deep.
winISD shows for a 69L box not including the port, the port comes out to be tuned to 45hz
winISD show a massive peak at 65hz of like 5-6db
My question is, does the sub start to unload under the peak of 65hz or still under the tuning frequency of 45hz?
I think I got the subsonic filter at about 30hz.