Sometimes, the words of the prophets are written on the subway walls and tenement halls. Other times, their words and ideas are made manifest through a lifetime of diligent and thoughtful work. As an audio prophet, the late Jim Thiel was one of the latter type. For decades he stood in his pulpit, quietly preaching to the audio world the importance of time and phase coherence in loudspeakers. His commitment to these ideas led to speaker designs that exclusively used first-order crossover networks, and driver designs and layouts that made possible time- and phase-coherent response. The speakers he created in turn built his company, Thiel Audio, into one of the more recognizable fixtures of high-end audio.