What is the best speaker wire to use?
Again, there is much debate over the benefit of the various schemes that are being used by different manufacturers. In general, however, you will probably want to upgrade your speaker wire from the factory ~20 gauge to something bigger when you upgrade your amplifiers and speakers. In most cases, 16 or 18 gauge should be sufficient, with the possible exception of high-power subwoofers. According to an example by Jerry Williamson, using 18 gauge instead of 12 gauge would only result in a power loss of 0.1dB, which is essentially undetectable by humans. Thus, other factors play more important roles in the selection of speaker wire. One issue is that different wires will have different line capacitances, which could cause the wire to act as a low pass filter. Generally, however, the capacitances involved are so small that this is not a significant problem. Be sure to heed the warnings above regarding cable flexibility and insulation, especially when running wire into doors and other areas