If you go with plate speakers most of them come with crossovers built in. Bass blockers are just a little coil of wire that you put in your speaker wire which filters out the low frequencies so your smaller door speakers dont distort from bass.

2000 SVT Black/Tan #1633/2150 (a few mods) Alpine: CDA-9835, MRV-F540, MRD-M550 PG: TANTRUM-X 6.5 COMP all around. Some people wear Superman pajamas. Superman wears Chuck Norris pajamas. CEL currently: Off