Please answer who technically experienced.
The theory behind a better speaker wire relates to the fact that higher frequencies (above 5000 Hz) travel on the periphery and not in the core of the wire.
So the effective cross-sectional area is lower and there will be a signal drop.
So, more than just increase the wire size, it's better to increase the number of strands.
Of course increasing both is best. How much to increase? It depends on the length.
You may have heard about Monster cables or other high quality brands. They all use larger number of strands than you'll find on regular electrical cables.
Would you notice a significant difference? Probably not.
Added: The effect of higher frequencies traveling on the periphery is called "Skin Effect".
Although it's highly theoretical, you can read about this here:
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