Abstract: A karaoke sound processor that automatically adjusts to the pitch of the singer's voice is provided. The pitch of the song signal recorded in the accompaniment recording medium for karaoke is detected by a first pitch detecting facility. The pitch of the song signal of the singer entered from the microphone is detected by a second pitch detecting facility. The two song signal pitches are compared in a comparing facility. When the pitches of the two signals are different, the output signal of the accompaniment is automatically changed by a pitch changing facility. The output signal of the pitch changing means and the signal of the microphone are summed up by an adder and produced. Without requring the singer to set the pitch change value, a karaoke sound processor capable of correcting the pitch automatically to a register comfortable for the singer is provided.

Abstract: A musical sound synthesizing apparatus which simulates a sound generating mechanism of a string instrument by using an electronic circuit comprises a driver for applying data, an adder, a delay unit for storing data temporarily, a low pass filter for processing data, and a word length designating unit for designating a word length (address width) of the delay unit. The adder, delay unit and low pass filter form a loop-shaped circuit, with their corresponding input ends and output ends connected with each other. The word length designating unit corrects a word length of the delay unit in accordance with a phase delay of the low pass filter or in accordance with the number of stages of the pipeline structure of the loop. In the case where a musical sound of the type generated by touching or hitting strings is synthesized, the driver reads at least two series of data stored beforehand and applies the read data to one of the inputs to the adder.

Abstract: The purpose of the present invention is to offer an electronic musical instrument which can synthesize the sound of brass instruments with fidelity and furthermore in real time. In order to achieve the above purpose, the musical sound synthesis algorithm is to utilize the tonguing information as well as the embouchure information in addition to the sound generation information, the frequency information, and the sound volume information, which have been used as the playing informations in conventional electronic musical instruments. Furthermore, by tabulating the functional relations between the above-mentioned playing informations and corresponding output waveforms, and storing them in memories, necessary waveforms for sounding the musical instrument can be obtained by only referring to those tables, thereby the speed-up, that is, the realization by hardware, can be realized and thus the sound of brass instruments can be synthesized with fidelity and in real time.

Abstract: In an analog-to-digital (A/D) converter or a digital-to-analog (D/A) converter, a nonlinear D/A converter is employed. The nonlinear D/A converter comprises an absolute value circuit, a D/A converter, and another D/A converter having a function of multiplication. The latter D/A converter is responsive to a digital signal and to an analog signal from the former D/A converter so as to produce an analog signal indicative of the square of the digital signal. In an A/D converter, the nonlinear D/A converter is put in a negative feedback loop following an output of a successive approximation register so as to produce a reference signal with which an input analog signal to be converted will be compared by a comparator. The invention enables A/D conversion of a wide dynamic range signal by using a small number of bits, while quantization noise with respect to a low level signal is maintained low.