14ga romex for speaker cable and X/O wiring


I know you recommend 16 or 18ga stranded wire and don't like the magnet wire due to the high resistance, but is there any problem with using 14ga solid core house wiring? It's cheap and low in resistance for longer distances like I need between my living and dining room areas.
And would it be good to twist it together or separate the pos and neg runs?
Thank's
Mike H.


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