Mmakshak, I tried running my Nuforce Ref. 9s single-ended (directly from my APL Denon), but I got quite a bit of noice (hum). A friend of mine also tried running his Opus CD Player direct using single-ended interconnects to my pair of Nuforce and experienced the same noise problem. So I've been running balanced cables from my APL to the Nuforce, and the noise is much lower (almost inaudible). By the way, the Nuforce (and the APL) are very revealing, so any change in cabling you will hear. Wait until your APL Denon has about 200 or more hours of burn-in. It is really a magical player. Have you tried running the APL direct to the Nuforce? Does yours have the AKM DACs? I am very happy with this combo. Now I just some room treatments to dial things in.