Camp,
It hasn't escaped me. Most even have crossovers higher than 80Hz. Some have 90Hz and some have 100Hz, some even higher. How many can you think of that have lower than 80 besides Outlaw?
Jeff,
When the THX standard crossover point is 80Hz, what good will a speaker do that goes down to 40Hz? I'll tell you... it will "TRY" to produce frequencies that the subwoofer is suposed to and screw it all up with distorted, muffled, muddy bass that should be the job of the sub anyway...