the numbers you get from a tech shet are so its safe.... companies wont give you what it will be loudest at, cause they don't want a warrenty issue... the guys on here.. i think prolly know as much if not more that the guys at the company, cause all they do is look up the info on a tech sheet, the guys on here and tested tried and tuned, and know what works best. I must say thank you to a few people on here for a lot of info I have used. talk to foreverbumpin, he seems to know his junk. 2.6ish you say for a 12" sounds about right depends on the box design and power, but i would try it, shit my box is like 4.96 for my mojo 12"