Lalitk, I'm running the DV2 directly to my Classe' CA M600 mono blocks,,,I do not have the REF PRE AMP, I did try using my Classe' Sigma SSP pre amp...Didn't like the veiled sound of that combo...I'm always attempting to improve SQ...Still curious how the N10 compares to the NS1...I can still play Hi Res files, and DSD...I assume you are using USB?