Multiple fans = how many db?

[oc jason]

if i use 4 32db fans in a case what db do i have then, i have forgotten the formula, ima use 4 37 cfm 32 db fans in an antec case and wondered how loud tha will be

[RedDeathDrinker]

I've got 3 80mm YS-Tech's at around 30cfm's each.

Jet engines are quieter............(but the case sits at just above eye-level in front of me. It's quieter under the desk...)

[The Overclocker]

i dont know the fromula, but think of it this way, if you add 1 liter of achol that is 60 % to another liter bottle that is 50 % you dont get 110%, you get 55%.
so if all of the fans are the same in theory they should all be the same noise as one