If you're running deck power to your fronts and your front speakers come with a crossover (Infinity Kappa 62.5i) as well as your H/U, where do you crossover? Do you run full range from the deck and allow the external crossovers supplied with the speakers do their job, or do you set the high pass filter at the deck as well? Now, this hypothetical set-up is without a separate sub at the moment.

What's the best scenario for the cleanest sound?

 

You will want the full range signal to go to the crossover supplied with the speakers. The external crossover (came with the speaker) will take the incomming signal and divide it to the tweeter and woofer. If you crossedover the signal right from the deck, there would be no separation for the high and low freq. to go to the tweeter and woofer respectivly.