dead quiet

Eldarford... The object of the game here in Audiophilia, is to get the purest signal devoid of any artifacts of any kind. One of the reasons that a 15000 dollar amp is better than a 1500 dollar amp is that the parts are better...that is faster (don't hold on to the signal as long), wider, and smoother bandwidth, etc. A component is said to be good when it passes only the intended replication of (let's say the violin). When the purity of the violin's E-string has a 60 cycle modulating tone along with it...it ain't so pure. One of the things that good stereo systems do is to stop playing...that is - there are silences between the notes. Hum and noise simply fills in those silences and blurs things. A very important spec specified on evalutaion sheets is the hum/noise level below signal. No - I must stand by my statement above.

Stringreen...So, when the tuba plays 60 Hz, the violin is messed up. Not in my system. Maybe in yours.

Actually, Eldarford..yes. When a tuba plays a 60 Hz. tone, it is resonated on the box and in the string of the violin...that's why playing "in tune" is so important when playing in an orchestra... a tone that "rubs" against the harmonic tones of the rest of the players makes people wince. That is also why most violin concertos are in D...because the other strings will resonate and strengthen the open strings...E, A, D, G,. In stereo system, you want NOTHING to detract from the original event...it's not like playing the violin since then you are constructing your own event...the event becomes truth. That's the meaning of high fidelity...truth to the original event. Hum and noise ain't an original event.

Stringreen,
While I agree with basically everything you have said on this issue, I have to inject something here. Unless, the performance is TOTALLY played acoustically, ie no amps, PA, etc., hum and noise are part of the original event. 100,000 watt PA systems aren't that quiet.

I used to run sound........

Stringreen...OK. OK...but if your hum is loud as a tuba your system needs repair :-)