The Alpine and HK systems seem to be similar since they are amplified. Low level signals come out of the head unit and the dash signals have an electronic crossover that filter out the low frequencies (aka high pass filter aka bass blocker). No physical bass blocker is needed for either of these "premium audio" systems.
The base 6 speaker audio is amplified in the head unit so high level signals go straight to the speakers (through the ANC unit under the driver's seat...which is not an amplifier for the base audio). There is no electronic "massaging" of the frequency band prior to going to the speaker so the full range is sent to the dash speakers. There is a capacitor soldered onto one of the terminals of the dash speaker that confirms this.
I'm not sure if you've read this thread but it is all explained in there:
Do you feel the JL are somewhere between the infinity and Faital?
5thgenrams.com
One of the posters mentioned installing the faital PROs without bass blockers initially but went back and installed them and was happier with the sound.
I installed the 8 ohm faital PRO 3FE22 speakes with bass blockers and am really happy with the choice. With my current EQ settings I can crank up the volume to distortion on the door speakers and the dash speakers are still clear.