My question is how do i match Amps to speakers in terms of RMS value, is it better to run higher RMS or to underpower your speakers and run with lower RMS. I am currently running PDX-f4 that gives out 100W per channel and i was thinking of upgrading to PDX-F6 that gives out 150W per channel..would this decision be SAFE??!

I am running the following :

(front) focal krx2 - Max. power 200W

- Nom. power 100W (2 way component kit)

(behind) Focal 165 cvx - Max. power 140W

- Nom. power 70W ( 2 way co-axial kit)

Amplifier- Alpine PDX-F4

100 watts x 4 chan @ 2 ohms, Total RMS: 400 watts, Signal-to-Noise Ratio: 76dBA,

Alpine PDX-F6

150 watts RMS x 4 at 4 ohms (150 watts RMS x 4 at 2 ohms)