ArJuna

I know this is an old thread, but I have direct experience and it is safe to say that this response would apply equally to differences between the RP-260F vs. RP-280F or the newer models, but identical RP-6000F vs RP-8000F. My room is about 20' x 24' I have owned Used the RP-260F, RP-450C, R-115SW x 2, plus RB-61 II surrounds and rears, and RP-140SA Atmos for three years. I originally wanted the RP-280F mains, but I was concerned about the size and the RP260F's were at a good price. I've used a Denon AVR-X3300W for about a year, and two years ago upgraded to a Denon AVR-X4300H (125w/ch). I began to have concerns about the heat generated in the X4300H driving 7.2.2 speakers. Even with two usb powered 120mm fans on top of the Denon drawing heat up and out and the Denon being mounted on a wire rack it got hot. i decided to get an external 2ch amp to drive the RP-260's and bought an Emotiva BASX A-300 (150w x 2ch) to drive the mains and added a pair of RP-500SA Atmos speakers. This made a clear improvement in the clarity, dynamics, and overhead for the RP-260's, and the Denon now ran cool in nearly all circumstances. Now I just got a deal on the RP-280'Fs. I sold the RP-260F's. The difference is noticeable at higher volume levels. I always kept the volume a few db short of reference so as not to overdrive the 260's and they could still blast your ears off with amazing sound, but there was a tiny bit of strain in the 260s at near reference. Now the the 280's on the same system I (can tell you the sound a bit richer (even though they are set to small and crossover set to 80hz allowing the R-155SW's to handle the low end), and they do not strain AT ALL at full calibrated reference levels (and more). They have not had any time to break-in, so I expect they'll be even better in a week or so. So in the end I can vouch that even though anyone would be thrilled with any of the combinations I listed above, the addition of a separate amp for the mains and then now the upgrade to the RP-280F were both noticeable improvements. Another somewhat unrelated tip that might apply to some. This system in in our master bedroom. Unfortunately, I was unable to mount the left main on the floor because of a 3-foot tall dresser exactly where it needed to be. My solution was to flip the left speaker upside down so the tweeters of both left and right mains ended up within a few inches of each other and right at ear level. This made a huge difference and there is no negative impact from doing so. Floor Speakers should not be placed sideways or you will screw up the designed horizontal dispersion, but upside down is fine.