Best bet with tuning is to work with a good design based around the subs, application, and your desired response. Pulling tuning out of the air will not always net the best overall results.@ double 07 I like the look of these. I have an 01 extended cab f150. I removed the backseats so I have plenty of room. I want a ported box and I would prefer it tuned between 32-36 Hz.