Signal generator for electronic musical instrument, employing variable rate integrator2010-03-05Apparatus according to claim 1, wherein said integrator means comprises an operational transconductance amplifier.
7. For use in an electronic musical instrument, a signal generator for
generating a single cycle of a triangular waveform, comprising integrator means, comparator means connected to said integrator means and responsive thereto for producing twodiscrete output voltage levels in response to a comparison of the output of said integrator means with a certain value, means connected to said integrator means and operative to control the sign of integration of said integrator means, said sign ofintegration being opposite for two successive integration periods, and means for discontinuing operation of said integrator means after a single cycle of operation including two successive integration periods.
8. For use in an electronic musical instrument, a signal generator comprising variable rate integrator means, means connected with said integrator for controlling the sign of integration of said integrator, said sign of integration beingopposite for successive integration periods, a potentiometer, first connecting means for connecting a first end of said potentiometer to a source of reference potential, second connecting means for connecting a second end of said potentiometer to saidreference potential, means for connecting the tap of said potentiometer to said integrator for supplying a signal to said integrator means for controlling the rate of integration thereof, and means for operating said first and second connecting means oneat a time during successive periods of operation of said integrator.
9. Apparatus according to claim 8, wherein said last named means comprises a bi-stable device connected with said comparator means and operative to energize said first and second means selectively in response to the output voltage of saidcomparator.
10. Apparatus according to claim 8, including manually adjustable means for controlling the scale of the time rate of change of the output of said integrator means, whereby the period of the waveform produced at the output of said...
Electronic musical instrument with automatic and semi-automatic playing apparatus2010-02-05signal;
play mode switching means responsive to the semi-automatic playing pause signal produced in the semi-automatic playing for switching from the semi-automatic playing to the automatic playing; and
a tone
generating means responsive to a selected one of the semi-automatic play and the automatic playing for performing the tone generation according to a pitch information contained in the playing data at one of the first and the second tone generation timings.
2. An electronic musical instrument according to claim 1, further comprising a key-depression timing displaying means for producing a stimulation indicative of timing for key depression at the second tone generation timing controlled by the automatic play timing controlling means in the semi-automatic playing.
3. An electronic musical instrument according to claim 1, wherein the stimulation is at least one of a visible display, an audible sound and a mechanical vibration.
4. An electronic musical instrument according to claim 1, wherein the automatic playing upon being switched from the semi-automatic playing starts from a paused part of the playing data where the semi-automatic playing was paused.
5. An electronic musical instrument according to claim 1, wherein the automatic playing upon being switched from the semi-automatic playing starts from a part of the playing data which is earlier than an instant when the semi-automatic playing was paused.
6. An electronic musical instrument according to claim 1, wherein the automatic playing upon being switched from the semi-automatic playing starts from the front of the playing data for a piece to be played.
7. An electronic musical instrument according to claim 1, wherein the play mode switching means is responsive to the key-depression signal which is issued in the automatic playing that has been switched from the semi-automatic playing for switching back the automatic playing to the semi-automatic playing.
8. An electronic musical instrument according to claim 1, wherein further comprising:
an automatic play request counter for updating its count value at intervals of a predetermined period in the automatic playing which has been switched from the semi-automatic playing;
a read timing counter responsive to the key-depression signal in the semi-automatic playing for updating its count until it coincides with a step time contained in the succeeding tone information;
a read timing counter updating means for adding a count, which corresponds to a time elapsed after a preceding key depression and calculated on the basis of the count of the automatic play request counter, to the count of the read timing counter; and
said tone
generating means producing a musical sound when the count of the read timing counter coincides with the step time.
9. An electronic musical instrument according to claim 1, wherein the first predetermined period of time for detecting the pause in the playing is a time elapsed after an immediately preceding generation of the key-depression signal.
10. An electronic musical instrument according to claim 9, wherein the first predetermined period of time is adjustable.
11. An electronic musical instrument according to claim 9, wherein the first predetermined period of time is a sum of a time from generation of the preceding key-depression signal to the succeeding key-depression defined by the playing data and a second predetermined time.
12. An electronic musical instrument for being selectively switched between automatic playing, for carrying out musical tone generation according to timing information and tone information contained in a playing data, and semi-automatic playing, for carrying out musical tone generation according to the tone information, in response to key depression of a player, comprising:
key means for entering timing commands for tone generation;
key-depression detecting means for detecting the operation of the key means to produce a key-depression signal;
semi-automatic play timing controlling means responsive to the key-depression signal for controlling a first timing for tone generation in the semi-automatic playing;
automatic play timing controlling means responsive to the timing information for controlling a second timing for tone generation in the automatic playing; and
key-depression timing display means for
generating a stimulation indicative of the timing for key depression in the semi-automatic playing, at the second tone generation timing controlled by the automatic play timing controlling means.
13. An electronic musical instrument according to claim 12, further comprising
a tone
generating means responsive to a selected one of the semi-automatic play and the automatic playing for performing the tone generation according to a pitch information contained ...
