Hi bmichels, I tried RCA out to Tu-05 and conclusion for me is that Hugo amp has better slam and details with TH900. The more i make comparison with my other gears, the more i think CHORD has strike gold with this little fellow. This is the closest to portable High-End so far for me. The quest is never ending but i am glad after spending Head Fi $$$ last 2 years, the bar has been raised. IMO.