I wouldn't think it would need an amp.
They're separates, rated @ 70 watts. I'm only using the mid driver since they're only in the rear (tweeters would pull the soundstage to the back), powered by the Alpine @ 27 RMS, 60 peak.
My CDT's senitivity are 91 to the MB's 86, so I figured with the radio equaly balanced (or near so), the rear wouldn't detract to much.. (Thinking about it now though if the difference is 86 to 91, is that percieved sound twice as loud? (3dB being double)