NewBuyer;212984 Wrote: > Ah, but I did not say "impedance matched" (as in equal > source-output/load-input impedances), but "impedance balanced" - > meaning equal positive and negative signal line impedances to ground. OK, I see what you're getting at. However, if you think about it, it is impossible for the impedances of the two sides of a balanced line to absolutely identical - there is bound to be some slight difference due to component tolerances. And at the same time, there is only one signal line in an unbalanced connection, so there is nothing for that to be "out of balance" with.
I think the common (and incorrect) description of the ground connection being the "return path" in an unbalanced connection is clouding the issue. There is no "return path". The signal seen by the receiving device (eg. the power amp) is the voltage difference between two wires. In the balanced case, it's the difference between the hot and cold signals; these are nominally symmetric and out of phase, and completely independent of the ground. In the unbalanced case, it's the difference between the signal and ground lines; the ground line in this case is nominally at 0V. As I said earlier, I wonder if it's the grounding arrangement that makes balanced a bit better. That nominally 0V ground line cannot be exactly 0V all the time. I wonder if noise on the ground line modulates the signal in the unbalanced case (not in the sense that it changes the signal line voltage, but that the difference between signal and ground is being affected). -- cliveb Transporter -> ATC SCM100A ------------------------------------------------------------------------ cliveb's Profile: http://forums.slimdevices.com/member.php?userid=348 View this thread: http://forums.slimdevices.com/showthread.php?t=36550 _______________________________________________ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
