Since the number of audiophiles worldwide represent less than 1% of the population - NO measurable effect! Now about those billion motor vehicles ...
Do you leave your components on 24/7?
Lately I've been leaving my components on all the time, on the assumption that a) they'll be ready when I want to listen, and b) the on/off cycle ages the equipment (tubes, anyway) faster than leaving everything on. Is the latter a reasonable assumption?