| 摘要 |
PURPOSE:To improve the sound quality of a recorded orchestral accompaniment device by connecting a compact disk main body to a key converting part via an interface circuit in order ot convert the digital data on both L and R channels into analog signals. CONSTITUTION:The data on both L and R channels are delivered serially with the master clock frequency from a compact disk main body U1 and then superposed on each other within an interface circuit U2. Then both data are written to RAM1 and RAM2 with the write control signal supplied from a key converting part U3. Then a pitch converting operation is carried out in a rate corresponding to the frequency ratio between both writing and reading clock signals. Then these digital data undergone the conversion of frequency in said rate are converted into analog signals through a D/A converting part and at the same time separated into L and R signals. Then distortions of the data are eliminated by AP1 and AP2, and these data are led to a loudspeaking means. As a result, the range of application can be increased for a CD device and the sound quality of the accompaniment play can be improved. |
