Apparatus for displaying musical notes indicative of pitch and time value

Abstract

An input audio signal is analog-to-digital (AD) converted into digital data which is processed by a central processing unit (CPU) for determining pitch of each sound by effecting Fast Fourier Transform (FET) operation and power spectrum calculation. The determination of the sound pitch is effected twice in sequence, and by using frequency and level data resulted from two consecutive determinations, the time length of the sound is detected. After the pitch and the time length are determined, data indicative of a given musical note pattern is produced so that a musical note indicative of time value is indicated at an appropriate position on a staff displayed on a screen of a display unit. Such data from the CPU is fed via a video display processor to a video RAM to be stored therein where the video display processor produces a video signal fed to the display unit in turn. In one embodiment, a note indicative of only sound pitch is displayed immediately after the pitch is determined, and the pattern of the note is changed to indicate time value if the sound is detected as a continuous sound. In another embodiment, the relationship between the time value of a note and actual time length can be manually set so that desired tempo can be selected. Furthermore, rhythm sounds corresponding to a selected tempo may be emitted, while data indicative of the selected tempo may be displayed.