The electrical properties of a cable can also affect the performance; of an amp i.e. capacitance and inductance.
E.g naim amplifiers really like low capitance speaker cables and actually sound worse when used with higher capacitance cables. Naim also recommends a minimum and maximum length of cable to be used. Naim own speaker cables are among the lowest capacitance cables out there.
Also the inductance may also have a detrimental effect, but to a lessor degree.
High capacitance cables can also act as a filter that also affects the sound and possibly an apparent volume change.
E.g naim amplifiers really like low capitance speaker cables and actually sound worse when used with higher capacitance cables. Naim also recommends a minimum and maximum length of cable to be used. Naim own speaker cables are among the lowest capacitance cables out there.
Also the inductance may also have a detrimental effect, but to a lessor degree.
High capacitance cables can also act as a filter that also affects the sound and possibly an apparent volume change.