Its actually not that much flow. After headloss and whatnot its not very bad. The fish don't even seem to notice to tell you the truth.
If you are looking in the 1700-2400 GPH range, you may want to consider a Reeflo Snapper. More energy efficient than the Poisiden pumps and cooler, but are louder. You won't hear it if the pump is in the cabinet though. Plumbing is a pain though since it is a 2" inlet and 1.5" outlet.
Alternatively you can pick up something like a Iwaki or Mak 5 and do the fan mod on it. Haven't done this myself but the guys over at reef central seem to love it. I can't seem to find the link though at the moment...basically you remove the fan and fan shroud from the back of the pump and replace it with a much quieter CPU fan with a PVC shroud to direct the flow of air over the pump body.
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32"x32"x20" Cube-ish tank
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