Acoustic design for large performance spaces has come a long way. Concert halls and opera houses are being planned or built in Orlando, Las Vegas (really!), Kansas City, and Midland, TX, as well as in China, India, and the relatively stable parts of the Middle East. But will they sound substantially better than halls built 100 years ago? Of course, safety and air systems have improved. And the US has learned the lessons of “potty parity” — new halls are doubling the numbers of ladies'