Research And Implementation Of Digital Audio Device

With the development of DSP technology, more and more audio products began to be digital.Many research institutions and famous enterprises have started to research the realization of digital audio products.The implement of digital audio equipment based on DSP chips, has caused widespread concern.This paper describes the basic principle of the parametric equalizer, then it studies the algorithms of the parametric equalizer. In this paper, a common design method of parametric equalizer has been studied, and an improvement is proposed to resolve the bug of common methods when upper limit frequency is above fs/2.The upper limit frequency is transformed from octave bandwidth. This improvement eliminates the impact to other frequency responses. It also studies the realization structure of the parametric equalizer and describes the directⅠ,-directⅡand lattice structure.It compares the three realization structure, too.During theoretical research,this paper also implement the three realization structures of parametric equalizer with C language, and verify the result of the three realization structures.It also describes the result of the improved method.According to the characteristics of the audio signal processing, TMS320C6747 is choosen as a suitable DSP chip.This paper also describes the performance of the chip,and then migrate these codes into the DSP chip.Based on the characteristics of the chip and procedures,it desicribes some optimization methods of partial modules and optimize the structure of the primary modules.This can reduce the computation to achieve real-time processing.