| 摘要 |
PURPOSE:To perform a PCM sound recording/reproducing method with high quality, by transiting the phases of low and medium sound ranges in particular of an audio signal before A/D conversion of this signal and then transiting and restoring these transited phases after D/A conversion. CONSTITUTION:The waveform of an original audio signal obtained at the most important time point receives a phase transit previously and is therefore converted into a waveform of large amplitude. Then the audio signal is recorded after A/D conversion, and an adverse phase transition is carried out again and substantially after D/A conversion to obtain an audio signal having an extremely small number of errors. It is desirable to restore substantially both the phase and amplitude to have a phase transition. Then it is desirable to increase the amplitude of a low range as much as the dynamic range permits at a phase transition that has a change of amplitude during a course. In such a way, it is possible to perform the PCM sound recording and reproduction with high quality. |
