Dave,
No I have not tried solid core so my experience is limited to ordinary stranded cables of several types (including extension cord cable, lamp cord, monster etc.) and none have made a wit of differece to my tin ears except that I felt much better about using thicker (higher AWG) cables for long runs (as per JBL table). I have not tried difficult load speakers or amps with high output impedance - so I have been in the situation of using gear that is likely to be only very modestly affected by a change in impedance - slight enough that it is inaudible to my tin ears.
No I have not tried solid core so my experience is limited to ordinary stranded cables of several types (including extension cord cable, lamp cord, monster etc.) and none have made a wit of differece to my tin ears except that I felt much better about using thicker (higher AWG) cables for long runs (as per JBL table). I have not tried difficult load speakers or amps with high output impedance - so I have been in the situation of using gear that is likely to be only very modestly affected by a change in impedance - slight enough that it is inaudible to my tin ears.