I have the Rokit 6s with no sub and they sound fantastic. They do drop off in the very low bass region (I am thinking 60Hz or so) but what is there is very clear and punchy. I am looking into getting a sub but I don't need it by any means. I supposed if you're only mixing dubstep with sublow frequencies these monitors could be frustrating but I disagree that they sound "lame and hollow." I suppose once you get the sub though it's hard to go back.
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