I would wonder how those numbers were arrived at.The FPB might sound a bit more refined but what speakers you need would also determine things.If you think you ever might get some really low impedance loads the KSA series was only one to ever remain stable into 1 ohm constant.That means my KSA300S can put out a whopping 2,400 @ 1 ohm.With Vanderteen's,Sonus Faber,Apogee's (but not Maggie bad match) etc this could come into play on the low impedance dips so amp does not shut down or clip.but it's also not power.,The 50 watt KSA is a cult amp that put zKrell on the map and is still one of Harry's faves.
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