PURPOSE: To generate an audio signal having maximum possible sensing quality by synchronizing the time envelope of noise signal to be modulated from a 3rd signal source with the time envelope of a cyclic signal and supplying the noise signal to be modulated to a coupling circuit together with the signal of a 1st signal source during operating while having the approximately equal energy at all times. CONSTITUTION: A 3rd signal source 14 generates the string or sequence of noise props and its envelope is synchronized with the time envelope of a signal generated by a 1st signal source 11. Namely, the sequence of noise props, namely, noises generated by the noise source 14 occurs at a repetition frequency Fo and further, all the noise props have the practically equal energy at least. The output signals of the signal sources 11 and 14 are mutually coupled by an adder 17 and amplified or attenuated by an amplifier step 18 as needed and then, the amplified or attenuated signal is supplied to a coupling circuit 13. Thus, voices much more natural than that of a device based on conventional technique are generated.
DEVICE FOR SYNTHESIZING SPEECH