I have a strange issue
When I'm using my Senn HD600 I don't receive any humm, But when I connect my new NAD viso HP50 I receive an annoying humm in my right ear. Not audiable when playing music but very annoying during silence. It isn't affected by the volumeknob
The HD600 has an impendace of 300ohm and the NAD has a impedance of 25 ohm. Could this cause this rather high pitched hum? And does somebody knows if it's caused by something in particular (already swapped tubes, problem remains right)
definitely the impedance of the headphones not being high enough for the output impedance on the amp... people had the same problem using low impedance cans with Schiit's Vali.