| 摘要 |
PURPOSE:To prevent the S/N from deterioration by controlling the DA converting gain at signal reproduction corresponding to a sequential sample value of a musical instrument tone extracted at each predetermined time interval to decrease distortion and quantized noise at a signal part of a small amplitude. CONSTITUTION:A signal modified in a way that the amplitude is multiplied by M every time the amplitude envelope of an original musical instrument tone signal reaches 1/M of the maximum value is stored in a ROM. In operating an operating button OPB, a digital data is read sequentially from the ROM by an address signal from an address counter ACT, and every time a code controlling the DA converting gain corresponding to signals Sc1-Sc3, a comparator COMP applies a shift pulse to a shift register SR and the gain of a variable gain DA converting circuit VGDA is modified into 1/M. In a reproducing signal outputted to a terminal 1 via sample-and-hold circuits SH, LPF, percussion signals are shown in solid lines from t1 to t2 and dotted lines after t2 as shown in Fig. |
