The high gain and low input sensitivity of the Nuforce STA200 will allow it to amplify any noise in the system preceding it ( including ac noise ). I cannot use the amp ( amps, as I own 2 ) satisfactorily with a few preamps I have lying around, as I hear a distinct hum through the speakers. The amp was designed to work passively, and this is best for it, ime.
Passive preamp issues or?
I have a Nuforce STA 200 that I’ve been using with an Axiom Walker mod preamp for a while now. Other equipment is a Bluesound Node 2 streamer and a Jolida dsd dac. Nordost digital coax and Dueland Schroeder IC’s from dac to pre and pre to amp. Last night, I disconnected the preamp and ran the IC’s directly from the dac to amp, using the volume control on the dac. The change in detail and depth was not subtle. Soundstage extended beyond the speakers- everything just sounded better. However, with the high gain of the Nuforce there’s a hum in the speakers- it’s not not audible when I’m not playing anything. I’m willing to live with it, but I’m curious why the sound improved significantly by pulling the pre- should I look at better IC’s from pre to amp or is the Axiom subtracting from the sound quality?