Abstract:
The electronic musical instrument comprises a plurality of slide-type faders ( 1 ), an interval setup device ( 5, 6 ), and a sound synthesis device ( 20 ). The slide-type faders are provided correspondingly to a plurality of tones included an interval and allow slide operations to change output sound volume. The interval setup device means sets the interval to define a tone for each slide-type fader. The sound synthesis device synthesizes sounds according to a volume changing pattern with predefined sound quality and based on operations of the slide-type fader. The slide-type faders can be manipulated by fingertips or the like for musical performance to enjoy the DJ play without many practices or high proficiency.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to an electronic musical instrument by using a plurality of slide-type faders preassigned with tonal intervals based on a specified musical scale and to a method of playing the electronic musical instrument.  
         BACKGROUND OF THE INVENTION  
         [0002]    A DJ play mixes different musics and reproduces the musics called non-stop remixes for a long period of time without interruption. The DJ play drastically develops by adopting the “scratch” technique which appeared in 1990s and uses the slide rheostat or resistor called the fader to create a rhythm by chopping up a music. The advent of this technique enables DJ devices such as a record player, CD, DJ mixer, etc. to be used like musical instruments. As a result, a new music genre was established and has become popular to the young generation.  
           [0003]    When DJ devices are used like musical instruments in a way completely different from that for conventional stringed or keyboard instruments, phonographic records or CDs are only presently available sound sources. Accordingly, the power of expression is greatly restricted.  
           [0004]    In order to enhance the power of expression, it may be possible to use a computer or a keyboard instrument. However, it is difficult to demand many practices and high proficiency from users in order to master the computer or the keyboard instrument anew in the field of DJ plays where many users create musics with acute sensitivity and based on their intuition. This makes it difficult for users to easily create music suitable for the DJ play.  
         SUMMARY OF THE INVENTION  
         [0005]    The present invention has been made in consideration of the foregoing. It is therefore a first object of the present invention to provide an electronic musical instrument which can expand the power of expression by diversifying sound sources in order to enjoy a DJ play using DJ devices like musical instruments and can easily create and perform music appropriate for the DJ play without needing many practices and high proficiency. It is a second object of the present invention to provide a method of performing such electronic musical instrument.  
           [0006]    According to the present invention, the first object is achieved by an electronic musical instrument comprising:  
           [0007]    a plurality of slide-type faders for changing sound volume of tones included in a musical interval, the respective slide-type faders being provided with the respective tones;  
           [0008]    an interval setup means for setting said musical interval to define the respective tones of the respective slide-type faders; and  
           [0009]    a sound synthesis means for synthesizing sounds having the respective tones with predefined sound quality, the changing pattern of sound volume of the respective sounds being defined based on operation of the respective slide-type faders.  
           [0010]    A slide rheostat or resistor is appropriate for the slide-type fader to be used here. It is preferable to use slide-type faders not fewer than the number of tone intervals included in an octave. For example, a chromatic scale begins a new cycle of an octave at the 13th semitone, forming a whole-tone scale (diatonic scale) in which seven steps correspond to seven notes for moving up and down 12 semitones. In this case, it is preferable to use at least eight slide-type faders.  
           [0011]    The interval setup means is preassigned with a plurality of scales such as the major scale (MAJOR), minor scale (MINOR), the other seven-note scales (natural minor scale, harmonic minor scale, melodic minor scale), and special scales used for folk or ethnic music. Selecting any scale can assign each slide-type fader with each pitch of the selected scale.  
           [0012]    In this case, it is preferable to provide an assign key for assigning each slide-type fader with a tone included in the selected scale. For example, the assign key is used to set C-Major, D-Major, and so on, and C-Minor, D-Minor, and so on.  
           [0013]    The slide-type fader enables performance using tones over an octave if there is provided an octave changeover switch that moves an interval up or down in units of octaves. The octave changeover switch may be provided to the respective slide-type faders as the number of intervals equivalent to one octave. It may be preferable to provide a master octave changeover switch, i.e., a switch that changes all intervals of all the slide-type faders in units of octaves at time.  
           [0014]    The sound synthesis means synthesizes sounds through an electronic circuit and may comprise: an AD converter which converts an output in proportion to the slide-type fader operation amount (stroke amount) into a digital signal; a CPU which issues a command for making a sound having predetermined characteristics defined by the digital signal; a DSP which outputs specified timbre data based on the command; and a DA converter which converts the timbre data output from the DSP into an analog signal. The analog signal output from the DA converter is amplified in an amplifier to drive a speaker in a manner similar to that for the ordinary audio equipment.  
           [0015]    The CPU issues a command to the DSP wherein the command not only specifies selection of the sound generation, envelope, sustain sound, and decay sound, but also indicates a sound volume. It may be preferable to add a key fader curve changeover switch to specify change characteristics of an output sound volume corresponding to a stroke amount of the slide-type fader. For example, this switch may be configured to select to gradually increase or decrease sound output with the lapse of time or to make the sound output constant, enabling more diversified performance.  
           [0016]    The sound synthesis means can use various sound sources. An external storage medium can be used to store sound source data in advance and this data can be read for use. If the sound from a microphone, phonographic record, or CD is converted into a digital signal, the DSP can process and store this data in memory. The data can be read out for use.  
           [0017]    According to the present invention, the second object is achieved by a method of performing an electronic musical instrument comprising the steps of: assigning musical intervals with different tones predefined by a sound synthesis means to a plurality of slide-type faders whose slide operation changes volume outputs; and varying operation strokes and operation speeds of the slide-type faders. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0018]    [0018]FIG. 1 is a front view of an electronic musical instrument as an embodiment of the present invention;  
         [0019]    [0019]FIG. 2 shows a configuration of a sound synthesis means used in the embodiment;  
         [0020]    [0020]FIG. 3 shows output characteristics of a slide-type fader; and  
         [0021]    FIGS.  4 A- 4 D show examplanatory characteristics of sound source output corresponding to a fader stroke amount. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0022]    In FIGS. 1 and 2, the reference numeral  1  represents a series of the slide-type faders comprising a group of ten keys. The respective slide-type faders  1  uses, for example, a slide rheostat or resistor and changes its output or an output voltage in accordance with the slide amount (stroke amount) of a key. As shown in FIG. 3, it is desirable that the output (voltage) changes in direct proportion to the stroke changes. The group of ten keys  1  is arranged so that a performer can simultaneously touch the keys  1  with fingertips of his or her both hands. Each key moves back and forth from the performer&#39;s viewpoint.  
         [0023]    The reference numeral  2  represents an octave changeover switch that is provided for each slide-type fader  1 . The toggle switch  2  is rockable back and forth (to the lower and upper direction in FIG. 1) and can automatically return to a neutral position. The toggle switch  2  increases or decreases a tone or pitch for the corresponding slide-type fader or key  1  on an octave basis. Pressing up the toggle switch  2  once and then returning it to the neutral position raises the tone one octave higher. Pressing up the toggle switch  2  for a specified number of times raises the tone higher for the corresponding number of octaves. Likewise, pressing down the toggle switch  2  for a specified number of times drops the tone lower for the corresponding number of octaves.  
         [0024]    The reference numeral  3  represents a master octave changeover switch which simultaneously increases or decreases tones of all the slide-type faders  1  on an octave basis. There is provided only one toggle switch  3  having the same structure as that of the octave changeover switch  2 .  
         [0025]    The reference numeral  4  represents a key fader curve changeover switch. The selection switch  4  can be set to three positions, i.e., neutral (B), forward (A), and backward (C), for specifying change characteristics of an output sound volume in accordance with the stroke amount of the slide-type fader  1 . That is to say, the selection switch  4  changes fader curves to three types.  
         [0026]    The reference numeral  5  represents a scale changeover switch. The switch  5  changes the musical scale of sound to be generated to the major scale (Major), minor scale (Minor), seven-tone scale (7th), folkloric scales (world1, world2), etc.  
         [0027]    The reference numeral  6  represents eight assign keys C (do), D (re), . . . , and C used for setting an interval of the scale selected by the scale changeover switch  5 . For example, it is assumed that the switch  5  is used to select the major scale (Major) and the assign key marked with “C” is pushed to be selected. In this case, tones or pitches included in an interval of C-Major is assigned to the ten slide-type faders  1  from the left to the right. The scale changeover switch  5  and the assign keys  6  constitute an interval setup means.  
                                                                       TABLE 1                           SCALE set to MAJOR            Interval           Selected by   Tone Specified to the Fader Nos.            Assign Key   1   2   3   4   5   6   7   8   9   10               C   C   D   E   E#   G   A   B   B#   D   E       D   D   E   F   F#   A   B   C   C#   E   F       E   E   F   G   G#   B   C   D   D#   F   G       F   F   G   A   A#   C   D   E   E#   G   A       G   G   A   B   B#   D   E   F   F#   A   B       A   A   B   C   C#   E   F   G   G#   B   C       B   B   C   D   D#   F   G   A   A#   C   0       C   C   D   E   E#   G   A   B   B#   D   E                  
 
         [0028]    [0028]                                                                       TABLE 2                           SCALE set to MINOR            Interval           Selected by   Tone Specified to the Fader Nos.            Assign Key   1   2   3   4   5   6   7   8   9   10               C   C   D   D#   F   G   G#   B   C   D   D#       D   D   E   E#   G   A   A#   C   D   E   E#       E   E   F   F#   A   B   B#   D   E   F   F#       F   F   G   G#   B   C   C#   E   F   G   G#       G   G   A   A#   C   D   D#   F   G   A   A#       A   A   B   B#   D   E   E#   G   A   B   B#       B   B   C   C#   E   F   F#   A   B   C   C#       C   C   D   D#   F   G   G#   B   C   D   D#                    
         [0029]    Table 1 lists intervals allotted to the slide-type faders  1  corresponding to the selected assign key  6  when the toggle switch (scale changeover switch)  5  is used to select “Major”. Likewise, Table 2 lists intervals allotted to the slide-type faders  1  corresponding to the selected assign keys  6  when the toggle switch (scale changeover switch)  5  is used to select “Minor”.  
         [0030]    The reference numeral  7  represents a control fader to select parameters for function keys  9  through  12  to be described. The reference numeral  8  denotes a display panel. The function key  9  is used to set a tone or timbre. Pressing the function key  9  defines a timbre to be assigned to the slide-type faders  1 . When the function key  9  is pressed, for example, numbers on the display panel  8  start blinking. Moving up or down a control fader  7  selects one of 99 timbres 01 through 99. Pressing an enter key  13  determines the timbre. Pressing the enter key  13  causes the numbers on the display panel  8  to light steadily, indicating that the specified timbre is assigned.  
         [0031]    The reference numeral  10  represents a function key for tuning (TUNE). Pressing the key  10  once can change the tuning by a half tone (100 cents) sharp or flat. That is to say, pressing the key  10  once enables the tuning mode. Moving the control fader  7  up or down can provide tuning by a half tone (100 cents) sharp or flat.  
         [0032]    The reference numeral  11  represents a function key for arpeggio setting. Pressing the key  11  enables automatic performance based on a predetermined sequence. The reference numeral  12  represents a function key used for setting various parameters when an external sound source is used with MIDI (Musical Instrument Digital Interface) system. The reference numeral  13  represents the enter key used to determine parameters for the function keys  9  through  13 .  
         [0033]    The reference numeral  14  represents a bend wheel. Rotating the wheel  14  back and forth can change a tone or pitch of the generated sound by a whole tone up or down. The reference numeral  15  represents a master fader and controls a master volume (not shown) for the sound. Moving the fader  15  to the right end provides the maximum sound volume.  
         [0034]    The reference numeral  16  represents a master fader curve changeover switch. The switch  16  can select one of fader curves A, B, and C for the master fader  15 . The reference numeral  17  represents a master equalizer, i.e., a 2-band master equalizer. The reference numeral  18  represents a level volume for headphone monitoring.  
         [0035]    In FIG. 2, the reference numeral  20  represents a sound synthesis means. The sound synthesis means  20  comprises an AD converter (A/D Matrix)  21 ; a CPU  22 ; a DSP (Digital Signal Processor)  23 ; memory  24  ( 24 A and  24 B) comprising ROM and RAM; and a CODEC (Coder-Decoder)  25 . The AD converter  21  converts an output (voltage) in proportion to the stroke amount of the slide-type fader  1  into a digital signal. The CPU  22  receives the digital signal from the AD converter  21  and issues a command for making a sound having predetermined characteristics based on the digital signal.  
         [0036]    Specifically, the CPU  22  issues a specified command based on signals determined by the slide-type fader  1 , the octave changeover switches  2  and  3 , the scale selection switch  5 , the assign key  6 , the function keys  9  through  13 , the fader curve changeover switches  4  and  16 , and the like. The CPU  22  is supplied with signals from the switches  2 ,  3 ,  4 ,  5 , and  16 , and keys  6 ,  9  through  13  via a switch (SW/Matrix)  26 .  
         [0037]    The DSP  23  is a so-called sound synthesis LSI and artificially produces sound through digital signal processing. The memory  24  (sound ROM  24 A and RAM  24 B) stores digitized sound signals or rules for generating sound and timbre data. The DSP  23  synthesizes or combines sounds based on the contents of the memory  24 .  
         [0038]    The CPU  22  can be supplied with sound source data (timbre data) stored in a storage medium  27  such as an external memory card via an interface (CARD I/F)  28 . More diversified performance becomes available through the use of sounds in the external storage medium  27 . A user can unlimitedly increase timbre variations using his or her custom-made sampling sounds or computer-based data files.  
         [0039]    The CODEC  25  is an integration of a digital coder and a digital decoder. The CODEC  25  is used to make it possible to use an external sound source  29 , other than the timbre data stored in the ROM  24 A; and data read from the external storage medium  27 , digitally processed and stored in the RAM  24 B.  
         [0040]    More specifically, the CODEC  25  is supplied with an output (analog signal) from the external sound source  29  such as a microphone, a record turntable, an MD (Mini-Disc), or a CD (compact disk) via an input toggle switch (Input Select)  30  and an input buffer (Input BUF)  31 . The CODEC  25  converts the input signal (analog signal) into a digital signal and sends it to the DSP  23 . The DSP  23  digitally processes the signal and stores it in the RAM  24 B so as to be used as timbre data.  
         [0041]    The DSP  23  reads timbre data corresponding to a specified sound source from the memory  24  based on a command issued from the CPU  22  and uses data read from the ROM  24 A to synthesize sounds.  
         [0042]    When the sounds are synthesized into a digital signal, the CODEC  25  converts this signal into an analog signal. The signal is then split into right and left signals which are amplified in amplifiers  32  and are transmitted to right and left speakers  33 , respectively.  
         [0043]    The following describes a method of controlling sound sources according to the apparatus. First, as mentioned above, the settings are configured for the function keys  9  through  13 , the scale changeover switch  5 , and the assign key  6 . The AD converter  21  is used to digitize (code) a full stroke (entire slide range) for any one of the ten slide-type faders  1 . Based on this data, the sound synthesis means 20 controls sound generation and envelopes.  
         [0044]    When the 45 -mm stroke length is coded into 8-bit 256 gradations (A0 to A255), the sound source is controlled as shown in FIGS. 4A through 4D. It is assumed that the key of the slide-type fader  1  is moved from the bottom to the top in FIG. 4A. When the key reaches position A10, the sound generation starts. Thereafter, the volume of sustain sound proportionally increases until the key reaches position A255 where the volume becomes maximum. Moving down the fader  1  decreases the volume. The sustain sound stops at position A9.  
         [0045]    Likewise in FIG. 4B, the sound generation starts at position A10 with the maximum volume. The sustain sound is continuously output up to position A255 with this volume unchanged. Moving down the fader stops the sustain sound at position A9.  
         [0046]    Likewise in FIG. 4C, the sound generation starts at position A10. The sustain sound volume increases in proportion to the stroke amount of the fader  1  between positions A10 through A64. Between positions A64 and A128, the sustain sound is output with a constant volume. At position A129, the sustain sound is released, and the attenuation control mechanism (sustain) starts operating. The sound attenuates in accordance with characteristics predetermined by the sound synthesis means 20.  
         [0047]    Likewise in FIG. 4D, the sound generation starts at position A10. Thereafter, the sustain sound amount gradually increases up to position A254 based on exponential curve characteristics. The sustain sound volume becomes maximum at position A255.  
         [0048]    In this manner, a performer presets volume change characteristics corresponding to the stroke amount of the fader  1  in accordance with his or her preferences. Then, the performer positions his or her fingers of both hands to the ten faders  1 . Moving up one or more of any faders can output the sound with an intended interval. Diversified performance is available by changing positions and speeds for moving the fader  1 .  
         [0049]    The tone or pitch of the respective faders  1  can be changed in units of octaves using the octave changeover switches  2  and  3 . Therefore, it is possible to perform wide-range music.  
         [0050]    The faders  1  can be used to control the sound generation and envelopes (patterns of volume change in time course) in two ways. The first method uses the fader curve toggle switch  4  for choosing from three general fader (envelope) curves (A, B, and C) to control envelopes. This method is mainly used for sampled timbres.  
         [0051]    The second method uses the memory  24  (ROM  24 A and RAM  24 B) to store timbre data in advance. According to this method, the memory  24  stores programmed data in accordance with various envelope curves as shown in FIGS. 4A through 4D. It is possible to optimize the preset timbre data. That is to say, this method is appropriate for preset timbres.  
         [0052]    As mentioned above, according to the present invention, intervals are preset to a plurality of slide-type faders and the slide-type fader is operated to change an output sound volume of the sound synthesized by the sound synthesis means. Accordingly, it is possible to diversify sounds of the sound source and enhance the power of musical expression.  
         [0053]    Since the slide-type faders can be manipulated by fingertips or the like for musical performance, everyone can easily enjoy the DJ play without many practices or high proficiency.