For example, a 16 AWG wire might work for runs up to 48 feet with 8-ohm speakers, but if the distance is longer, you should use a thicker speaker wire with a lower gauge number.

We discuss speaker wire gauge and how to choose the best audio cables based on your loudspeaker impedance and distance to your amplifier to achieve best performance. ... For example, it would take ...

A 4-ohm speaker draws more electric current through your AV receiver’s output transistors, and since more current equals greater power, 4-ohm speakers tend to have greater dynamic range and play ...

Most people have 8-ohm speakers, and 16-gauge is the typical go-to wire for that; it's adequate for a 48-foot run. A 100-foot roll of 16-gauge speaker wire is only $11.98.