[quote name='Bill Fitzmaurice' post='526481' date='Jun 28 2009, 04:34 AM']You can get away with it, but you shouldn't. High frequency output from the woofer will have a different phase response than the tweeter, causing destructive interference, and the impedance of the cab above the HF corner frequency will be 4 ohms, not 8. Many cab manufacturers do use a high-pass only, not because it's the right way, but because it's the cheaper way.
BTW, if you're adding a tweeter it should cross no higher than 2kHz with 12s, 2.5 Khz with 10s. Manufacturers usually go much higher, it's true, but as for why they do, see above. [/quote]
Thanks