As technologies like Virtual Reality continue to advance, realistic synthesis of spatial sound has become crucial for creating immersive experiences. Synthesizing the sound received at any position relies on the estimation of impulse response, which describes how sound propagates in a scene. While various learning-based approaches have been proposed, their generalization performance to unseen poses remains unsatisfactory. In this paper, we incorporate acoustic wave propagation principles to construct an impulse response field, achieving state-of-the-art performance in unseen pose synthesis. Our method utilizes volume rendering that encourages multi-pose consistency. To address the challenges associated with the wave properties of acoustic signals, we introduce frequency-domain signal rendering that can handle signal time delays and manage signal superposition. Extensive experiments show that our method surpasses the current leading methods by a substantial margin. Additionally, we develop an acoustic simulation platform that simulates more realistic impulse responses than existing simulators. The code and the simulation platform will be open-sourced to the community.