It can't hurt to see how they sound off the HU before you go out and buy an amp. Keep in mind your HU is 50x4 but that is max power, not RMS. Even if you get an amp that is say 50 or 75 watts RMSx4 it should be a great improvement. Just make sure to pay carefull attention to the power ratings of the amp you buy. It could say 1000 watts max power on the front and when you break it down it's rms ratings are nowhere close, and those are the numbers that are important.
