Soundsgoodtome
Headphoneus Supremus
Initial impression is very, very good. The Polaris has enough horsepower to drive the 560s with room to spare. Again, I haven't tried running with no input attenuation so the additional headroom available is unknown. I can say that with attenuation you can get to hearing damage volume.
I am tremendously pleased with the sound. Everything I have thrown at this combination is jaw dropping good. Fast, agile, nimble - every subtly is there. Firm, even sneaky bass. Not at all overblown. An overall feeling of untapped power ready to jump into action when needed.
In short, I'm keeping this combination. It is exactly what I was looking for.
Them guys over at the HE560 thread really need a tour model to try with theirs. It's an incredible combo