That's right Larry, a fair number of very large organs exist which can do 16Hz(there're a couple monsters that hit 8Hz), and the EP600 can indeed handle it(see
graph ). The basic principle is that an open pipe resonates at a fundamental frequency of the speed of sound divided by twice its length, so a 16Hz fundamental requires a pipe about 32' long.
If you're interested, there are quite a few pipe organ recordings that can give subs a real workout, and lists of recommendations are available on line.