another freakin amp question

[WSUDrummer]

ok if I have an amp that doesnt have a crossover built in, but a cd player that has high pass filter controls can I use that to control the frequencies for the front and rear speakers? I guess basically what im asking is when I hook the amp up to the speakers and hu will I still have control of the high pass filter function in the head unit or do I need to buy a crossover?

The hu is a pioneer DEH-P4800MP, the amp will be a JBL LC-A304, and the speakers are 2 pair of infinity reference 6x8

 

[toypaseo]

According to the manual, http://akamaipix.crutchfield.com/Manuals/130/130DEHP480.PDF , you can use the built-in crossover.