Here's some spec on impedance of my gears:
Linn power amp input impedance: 4700 ohms
Rougue preamp output impedance: 350 ohms
Paradisea Ouput: 2.0V, < 800 ohms
NAD C541i output impedance: 300 ohms
Marantz DR700: line output is 2Vrms, but no mention on output impedance
I've found that most NAD CD players have low impedance, e.g., C542 has 150 ohms. I did not care much about all those spec numbers since as long as one sound good it is OK with me.
Does anybody care about those impedance mismatching? If yes, why many vendors don't bother put them on the spec?