Abstract: The classical normal-mode theory expresses the steady-state sound field in aroom produced by a point sound source as a series of normal modes of vibration. Experimental facts are often not explained by this theory,and it was conjectured that the normal-modeexpression is not the complete solution of the wave equation in the room,but only the reverberant part of it,and there should be an additional term representing the direct spherical radiation to make the solution complete. The problem is examined by critically reviewing thederivation of the normal-mode expression and by theoretical analysis of the steady-statesound field in a room,and experimental measurements therein. The conjecture is confirmed inthis way,and it is definitely shown that the the sound field should contain the direct wave aswell as the standing waves （normal modes） formed under the influence of the boundary surfaces.Relevent mathematical expressions are derived