| 摘要 |
PURPOSE:To obtain announsing sound of good quality by changing the envelope time along with the change in the tempo of melody. CONSTITUTION:When a clock part 40 reaches the set time, unlocking 42 closes and the data of the note necessary for melody are supplied from a note ROM46 to a scale sound generating circuit 48, by which the scale frequency signal necessary for melody is created. On the other hand, the output of the note ROM46 is applied to an analog switch 50 and a variable envelope circuit 54 is selectively controlled according to the lengths of notes. As a result of this, if the lengths of the scales of the melody used as the announcing sound are long, the envelope time becomes longer and if the lengths of the notes are shorter, the envelope time becomes shorter. Hence, the electronic melody sound close to musical instrument sounds and natural sounds may be obtained. |
