- Dec 31, 2018
My past life was almost exclusively involved with professional Broadcast electronics, and there was never a single instance of a manufacturer stating any 'break in' time or anything of the sort. No professional user would be the least bit impressed if told that what they bought wouldn't work properly for a number of hours. It would immediately ring alarm bells as to stability. Why 'audiophiles' accept any less is a mystery to me, all part, I suppose, of creating a mystique that audiophile products transcend science and engineering.
Proper design can test for ageing through thermal cycling or damp heat testing, for which there are international standards. These can help predict infant mortality and long term ageing (the "bathtub") and pick off issues during the design phase. A proper designer will factor any performance drift over time OR environment (humidity) into the design margins required by the product to hold its spec.
I expect there are very few if any home audio manufactures that follow this rigour given that specification drift has few if any real comercial consequences.