stereo change

hope someone can help with this i have a 2000 w reg dhse with the alpine head unit and harmon kardon speakers i have put a new headunit in but im not getting any sound i think i know what the problem is i think you need to power the harmon kardon amp but i dont know how to please help thanks

In a DHSE you will have amps in each of the doors plus one of the side of the sub woofer.
If you have no sound you need to test each one of the amps.
your car will not have a harmon kardon amp like the Vogues have as yours wont have factory fitted nav.