in a previous life I went to school and qualified as an audio engineer, in Ottowa, which was then a hotbed of audio startups due to the ability to use the facilities at the NRC for testing and development, and there is most definitly certain characteristics that can be found in conductors, but no one at that time was suggesting that these were at the audible level, especialy for the very short lengths used in home or club systems. But on the other hand if you had a 300 mile long coil of wire bieng used in an anolog delay line, then perfection was barely good enough. Primary concern was shielding, and noise from power supplys, and generaly power supplys are still a huge source of noise. Consensus was to eliminate anything not needed from the signal path, and take care in creating a noise (buzz) free listening environment, with good spatial seperation. Major gear would have NO controls on the power amp, carefull ,carefull, everything in the preamp, cause it will launch your smoking speaker cones out where diagnosing the issue will be easy.