In this research, we propose a directional sound source representation technique for 3D contents such as volumetric video in metaverse and digital twin. Our proposed technique enables us to have a novel 3D audio-visual experience which is derived from immersive audio presentation expressing the radiation characteristics of sound source. To realize such an experience, we configure the spaced placement of paired microphone array and capture sound source signals completely without obstacles for volumetric video capture. Then, we synthesize the directional sound source signal using our technique which conducts signal processing to capture sound signals based on the positional and directional information of an object relative to a user. We developed and demonstrated a VR application using this technique to evaluate the change of sound with the object or user's movement in accordance with visual rendering. In our user study, we received lots of positive feedback for a novel audio-visual experience.