Yes, you can set up a speaker with a crossover based on theoretical values that will ensure you won't burn your tweeter or midrange drivers and you may sit back and think this is a great speaker - and maybe it is - but in most cases you wouldn't like it any more if you saw the measuring performance.
The crossover is the heart of the speaker and can be made in numerous ways and to a great extent determines the behaviour of the drivers.
Only minor changes can turn a great speaker into mediocrity and visa versa.
Here's some crossover calculators:
http://ccs.exl.info/calc_cr.htmlAlso, i cannot enough recommend reading the articles written by John Atkinson at Stereophile:
http://www.stereophile.com/searchresults/i...er+measurements