Why do Old Cymbals sound so Different from New Cymbals?

Theories and reasons abound of the differences between the sound of cymbals new and old. Perhaps it is because cymbals were once made by those craftsmen imbued with magic while the cymbals of today are made by mere Muggles. But far less exciting than that are the obvious reasons; manufacturing methods, sometimes as granular as how the employee who would melt the metal did something specific in the task, the flux that was used to keep oxide from forming, the actual amount of tin (Its not all actually B20! The actual percentage varies widely and those antique cymbals were subtly alloyed with other impurities in varying incidental quantities including impurities from the shop environment such as iron, not just trace amounts of silver as is commonly known.)

In fact the variation and even the imperfection of many of those old cymbals made them what they are. But even so, as the number of independent cymbal smiths in less than ten years has multiplied the experimentation of cymbal manufacturing well beyond what the major manufacturers offered in the previous century, the build-out, the materials, the patina, and all the other factors get very close, but there is one thing that they have not replicated, extended play time. The accumulation of vibration easing the internal stresses of the B20 alloy and exercising the vibrational modes of the all at once simple yet incredibly complex bronze disc we call a cymbal is in some ways the final frontier of cymbal smithing. Pre-aging a cymbal through vibratory stress relief to accelerate its maturity and help it settle-in could play a part in helping your cymbal settle into maturity.