Since there was very little consistency in the way polarity was handled when our stuff was recorded in the first place, and since many speakers do not maintain polarity coherence in the way they are wired (making polarity changes inaudible or nearly so), you don't gain much by switching speaker wires. CDs/LPs/tapes were recorded in inverted, non-inverted, and mixed polarity. If you can clearly detect polarity changes, you're best off with a preamp (like my Aesthetix Calypso) that lets you switch polarity from the remote.