I've been really looking hard at buying the Diamond Audio S600S 6.5 components. My question is: The specs say 170 watts RMS and 340 peak. The amp I'll be using is a memphis MCA3004 which is only 75x4 RMS. Is this lack of RMS power going to affect the SQ of these components?
No, because if you are applying 75 watts per channel of clean power to a decent well installed component set, the volume will far surpass the range where SQ is the primary consideration. At high volume levels, our ears go into protective mode. Sound quality is appreciated at moderate volume when your ears aren't closing up to protect the eardrum.
The 170 watt RMS rating for the speakers indicates that they have been tested to achieve sound production at a lower freq than the typical mids-to-sub crossover point of 80 Hz (lower freqs take a substantially greater amount of power). That doesn't mean that they sound good at 50 Hz, though; the sub is supposed to sound good producing that freq range. Just a few watts is all that is needed for maximum SQ.
Listen to speakers first; consider their ratings as an afterthought. The 170 watt rating may be a clue that they will blend well with the sub by having a strong bass region, but listen to a few setups at the stereo shop before deciding.
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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.
Thanks for the reply. I did listen to the Diamond Audio 661a 6.5's that a friend has on a rubicon 604. He was putting 80 watts per channel on those and they sounded SWEET, but he was only running one pair of 6.5 compenents. I'll be running 2 sets (crew cab truck). That should be plenty enough loud and clear. I was thinking I would be safe and I would have "enough amp" for those as long as I stayed away from clipping.