Fair enough.

I've done the comparison enough times now to clearly hear the (admittedly subtle, but worthwhile) sonic improvements gained from, say, upgrading cheap, mass-produced, brass-constructed phono or banana plugs, with high-quality solid-copper or silver varieties.

However, for best results, the same has to be done on the sockets to which they connect

The problem is, most folks own commercially produced equipment and don't want to risk 'devaluing' it, fitting different sockets, and often having to drill out holes in cases, in order to get better ones to fit.

Marco.