I also have a a NC502MP I am a tiny bit worried that my Buckeye amp is a bit too powerful. I used to be able to play my Kef r3 metas at full range with Denon 6700h, but now with all this power even at low volume the speaker distorts with low bass. Is there a way to equalize this out because when I switch the speakers to small to try and set a crossover, it automatically adds the sub there's no way to get a crossover a certain level without the sub on...
For movies though I'm super happy I honestly enough the biggest difference I've noticed is in the surrounds. Now that the receiver doesn't have to worry about these heavy lifters at the front the surround is so clear. It is incredible for home theater but I wonder if I can figure out this music issue. Any suggestions? Do you also have this problem or are you just playing them with the subs?
I'm not having any of the issues you describe.
Unless you are playing at/above reference level (...and even then...), it is highly unlikely that your Buckeye is root cause.
My uneducated guess is that you may be experiencing either or both of these issues:
(1) You may be driving your R3Ms with music that has a larger percentage of information below 80Hz coupled with a higher volume setting on your Denon.
(2) Your source may have some measure of distortion contained within the music that is being amplified and then fed to your R3Ms.
For issue (1) you should set a proper crossover between your R3Ms and your Sub, start at 78-80Hz and then work your way up until you resolve the issue.
I've changed a number of pieces of gear in that system:
Bluesound Node 2i - miniDSP SHD - Buckeye NC502MP - KEF R3 (non-Meta) + Emotiva SE12 Sub
I have the speakers about 1.5 ft from the back wall, about 10 ft apart, the port plugs IN, and the R3 crossover set at 100Hz with 24dB/octave slope on the miniDSP SHD.
As I mentioned above, zero bass distortion issues. In fact, it sounds amazing.