well i went to local car audio shop and they measured out my trunk today and see what they could make... the guy told me if i wanted spl and some sq i should go ported tuned around 40 hz... i was thinking 40z?!?! wow... he says if i tune it around 34-36 hz it will not sound as loud as 40hz... he says that 40hz is good mix of both or something... what should i do? tell him i want it tuned lower or what?... - is it ok if its tuned at 40?...
For twelves and SQL, with more emphasis on SQ, 32-35hz is about right for most people's tastes. If you wanted more SPL while sounding halfway decent, 40 would cut it, but you'll lose low end (which is what Avalanches are better for anyway). Avalanches, Brahmas, and the XXX tend to be a bit muddy above 60hz, you'd be limiting your bandwidth by a good amount with a 40hz tune. Those subs in particular do better with a low tune, I'd personally take the SPL tradeoff and go 32hz at highest, but likely in the 20s for my tastes.