problem of point source amplitude in The Pressure Acoustic, Transient Domain

hi, I'm doing a simulation about the pressure acoustics transient domain.In my simulation,I use a point source as the input,and define the wave shape of the point source as sine wave.The problem is that when I defined the amplitude of sine wave as 100, the amplitude of wave at other points in my module is more than 100.It confuses me a lot.I want to know what could influnces the amplitude of the input wave. I hope anyone can help me solve the problem,thank you very much!