Wire! It makes a difference.

Wire. I view it as a tool as a final touch to help bring balance a system. Wire is not a major source of distortion, but is a source of noise. Other things like capacitance, and inductance can influence the sound of your cables and interconnects. The insulation almost matters more than the conductor. No insulation is best, but cotton is next best, and PTFE is nearly as good as cotton and is what I use because of it is much safer. And how the insulator on a wire affects its performance can be measured, so it is real. Although it isn't always a major factor in the overall sound of a system.