In this electronic musical instrument a musical tone is generated by repetitively reading out a waveshape stored in a memory. Repetitive sets of phase information are produced, such phase information thus being a linear saw-tooth-like digital signal having a repetition period corresponding to the frequency of the generated musical tone. Phase distorting means modifies the shape of the phase information so as to distort said linear saw-tooth-like signal, without changing the repetition period thereof. The resultant altered phase information is used to access said memory so that during the supply of each of said repetitive sets, successive samples in different portions of said stored waveshape respectively are read out at different effective rates. Thus the waveshape samples read out from said memory will constitute a musical tone having changed tone color but unchanged pitch.

In this electronic musical instrument a musical tone is generated by repetitively reading out a waveshape stored in a memory. Repetitive sets of phase information are produced, such phase information thus being a linear saw-tooth-like digital signal having a repetition period corresponding to the frequency of the generated musical tone. Phase distorting means modifies the shape of the phase information so as to distort said linear saw-tooth-like signal, without changing the repetition period thereof. The resultant altered phase information is used to access said memory so that during the supply of each of said repetitive sets, successive samples in different portions of said stored waveshape respectively are read out at different effective rates. Thus the waveshape samples read out from said memory will consitiute a musical tone having changed tone color but unchanged pitch.

An apparatus for forming a musical-tone waveform for an electronic musical instrument characterized in that at least one cycle of a musical-tone waveform, which it is desired be produced, is divided in amplitude by dividing lines at equal intervals and sampling points on a time axis are determined from respective crossing points between the waveform and the dividing lines and the distance between the initial and the final sampling points is represented by an appropriate number of pulses so that each sampling point may be represented by a pulse number. There is further provided a memory circuit wherein each sampling point, that is, the pulse number thereof is set up in the form of a digital signal. Additionally, there is a set up in the form of a digital signal a tendency such as increase, decrease or equal at each sampling point with reference to the preceding sampling point. An envelope setting device is used wherein the envelope of a muscial-tone waveform, which it is desired be produced, is subjected to sampling and the analog amount of each sampling point is set up in the form of digital signal. An accumulatively adding device is employed whereby the output digital signal of the envelope setting device is accumulatively added to or subtracted from the output digital signal of the memory circuit. The accumulatively adding device is connected at its output terminal to a D-A converter for converting its output signal into an analog signal.

An electronic organ has a tone generating system for producing tones corresponding to notes of a musical scale. The tones and combinations thereof are selectable to provide different characteristics or "voices" which duplicate the various voices which are selectable on a pipe organ. The character of each such voice is determined by a single generator. The character of the output tone on a per manual basis is alterable by substituting or combining the outputs of different generators. The signal produced in this manner is sampled at a rate which translates it to an audio frequency.

A signal processing system records and reproduces a music signal which varies repeatedly. The music signal is sampled at a given sampling period and pulse row obtained from the sampling is rearranged into a given pattern to achieve a new pulse row which is stored. For read out from a storage medium, a read-out means reproduces the original pulse row sequence and provides a wave form of the original music signal.