On every piece of audio gear I have ever owned or had direct experience with the "peak" ratings (whether that be a wattage output rating on an amplifier or a head unit...which is still talking about the inbuilt amp OR the wattage input capability on a speaker or subwoofer) is good for nothing better than to help some marketing guy to meet his quarterly sales quota.
RMS ratings are much more indicative of actual, real world, usable figures. As previously stated by TeeBone already in this thread, even the RMS numbers will rarely, if ever, actually be met by the average user - especially playing music as opposed to a test tone sine wave.
bdawson tell your friend if he wants to fall for the marketing hype he is more than welcome to - some company's advertising department will have done their job and he (your friend) can have the satisfaction of making someone feel as if they have done what they were hired to do but do not expect any great deal of performance for having fallen for the impression that the amp he just purchased which has 1600 Watts Max Power! garishly emblazoned across the topside of the chassis will EVER give him 1600 usable watts.
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