Bill (Grannyring), the two ways in which high output impedance of a line level component are most likely to have audibly significant consequences are:
1)Interaction of VARIATION of that impedance, as a function of frequency, with the load impedance, resulting in degradation of frequency response flatness and other effects.
If the output impedance is very low in relation to the load impedance, it assures that variations of that impedance will be insignificant in relation to the load impedance. But if the output impedance is relatively high, it does not NECESSARILY mean that those variations will be large enough to become problematical. A hypothetical output impedance that is purely resistive (as opposed to the impedance having significant capacitive or inductive components) will have no variation as a function of frequency, and assuming that the load impedance also does not vary significantly as a function of frequency the only consequence of that output impedance being high would be a slight gain reduction.
2)Interaction of that high output impedance with cable parameters, especially capacitance. If the interconnect cable is kept short, and a low capacitance cable is chosen, those effects will be minimized.
Happy New Year!
-- Al
1)Interaction of VARIATION of that impedance, as a function of frequency, with the load impedance, resulting in degradation of frequency response flatness and other effects.
If the output impedance is very low in relation to the load impedance, it assures that variations of that impedance will be insignificant in relation to the load impedance. But if the output impedance is relatively high, it does not NECESSARILY mean that those variations will be large enough to become problematical. A hypothetical output impedance that is purely resistive (as opposed to the impedance having significant capacitive or inductive components) will have no variation as a function of frequency, and assuming that the load impedance also does not vary significantly as a function of frequency the only consequence of that output impedance being high would be a slight gain reduction.
2)Interaction of that high output impedance with cable parameters, especially capacitance. If the interconnect cable is kept short, and a low capacitance cable is chosen, those effects will be minimized.
Happy New Year!
-- Al