I just compared the slow and sharp filters on my NS500V and the sharp filter is the one to use. Using the slow filter results in a smoothed, muddy sound, devoid of life and air.
With the sharp filter the life and air come back. I am using the NS500V as my main CD/SACD source, I prefer the sound to my older Denon DCD-1700 CD player.
With the sharp filter the life and air come back. I am using the NS500V as my main CD/SACD source, I prefer the sound to my older Denon DCD-1700 CD player.