I've only had it a few days. I did notice an improvement out of the box though. I'm using JRiver on my computer to an AudioQuest Carbon USB to the Luxman to a PS Audio Digital Link III connected to a PS Audio GCHA Headphone amp with a Kimber Kable DV-75 cable to my Sennheiser HD 650's  Hopefully after some long term listening I can give a more detailed review.