@Rufus T. Firefly
Yes I did read all the threads (back then before my purchase) and was also a little skeptical with all the complaints people had. All I am saying is that you should not disregard a product just because some lab measurement shows a certain performance metric subpar with other options. For instance in a blind test at home with my system I could never "hear" the difference between a $15 generic garbage DAC, Topping D50s, MiniDSP DRC, Yamaha A-S701 (integrated TI Dac) or the NAD C658. And I really tried hard
Same goes with different Class-D and Class-AB amps i blind tested. I could only tell when my 30Watt Class-A Tube Amp (845 Tube) was playing since it could not deliver the current for deep/loud bass in the low impedance area of my speakers.
I"m not saying that other people can't make out and maybe my hearing is just bad but in the end only my own perception matters. I like to encourage people to try the gear out for them self and make a educated decision to buy or not. For every product you will find someone one the internet that hates it
As far as Dirac goes It performs equaly well on the C658 as it does with my MiniDSP DRC: Lately I am just a sucker for that 60Hz room mode (+15db hump) in my listening position. If I correct that to the "Harman research +10db low boost" target curve in Dirac I loose that super deep punch. Compared to food it is like putting super spicy hot sauce into my food
I have to have fun when I listen to my music regardless of what the artists or mixing engineers original intend was!
I cannot comment on the SubOut since I am not using that feature.