On the sound field of a vault with two open ends

The sound field in a vault with two open ends is studied and its sound pressure distribution is compared with that in an enclosure and a long space. The accuracy of estimation on this kind of space by the classic Sabine Formula, the modified Sabine Formula and the ray tracing method are compared through numerical simulations and experiments. It is found that the sound field in this type of non-close space is not uniform, SPL declines faster near the openings, and RT values have a large span when the source is not at the center. Non-exponential decay is also found in this open vault, and the reason and precondition of its occurrence are discussed.