Luxman 509x vs Hegel H390

I think it does a great job, but depends on the recording and room.  It does not etch their location in space.

What it does is feel extended at the bottom and top end, making speakers sound like they go deeper and are smother long past the top of the speaker.  Compared to very neutral amps like say Parasound, they sound like bigger, faster amps.  Compared to Ayre, they don't have the same abyss from which music comes from.  Very close in tone and temperament to the D'Agostinos. 

The big reason for the 509 vs. the 507 is low impedance speakers.  The 509 is a little stiffer where your speaker's impedance dips thanks to the beefier power supply and another pair of output transistors.  Both great amps.