The Design And Implementation Of Digital Reverberation Audio-effect System

A digital reverberation-effect system is researched and implemented in this project. Arithmetic, hardware design and software development are analysed respectively. The system has three audio-effects, including hall-reverberation, room-reverberation and spring-reverberation. And the reverberation-time, tone, volume can be controlled.The theory of reverberation is introduced. Then the reverberation based on delay-line, comb filter and Schroeder-model are discussed respectively. According to the diagram of reverberation-system, the Early Reflection and Late Reverberation established by Gardner are analyzed. Hall-reverberation and room-reverberation algorithms implemented in this system are proposed. And spring-reverberation algorithm is also designed. In addition, the tone-control model is discussed.Hardware architecture includes control-subsystem, reverberation-process-subsystem and power-subsystem. After analyzing the requirements of system and the problems that should be paid attention to, high price-performance solution, which has confirmed the core-chip of each subsystem, is proposed. This paper mainly focuses on the design of control-subsystem and reverberation-process-subsystem. The peripheral interfaces and the communication interface are discussed in control-subsystem design. Then the audio interface, SRAM interface, FLASH interface and Host-port interface are discussed in reverberation-process-subsystem.In software development, communication protocol between MCU and DSP is defined. According to the data-structure of delay-line, the functions required in system are implemented in program language. And the BootLoader is also discussed in details.After nearly two years'work, this reverberation-system has been approbated by the cooperative company. And it has been produced.