I am going to install the APO for EQ'ing. Since I find the Arya Organics to be my end-game headphones, any real changes via EQ would be very minimal. I also have what I consider my end-game loudspeaker system as well. Topping a90d headphone amp/preamp>NAD 208thx power amp>aDs 910 loudspeakers>SVS and HSU Research 12" subs. If I find I want more impact I just go to my loudspeakers. For the best-sound all-around, I go with the Organics.