CN2113529U

CN2113529U - Tone turning device for karaoke

Info

Publication number: CN2113529U
Application number: CN 92205590
Authority: CN
Inventors: 章谦
Original assignee: Individual
Current assignee: Individual
Priority date: 1992-04-04
Filing date: 1992-04-04
Publication date: 1992-08-19

Abstract

The utility model relates to a tone turning device for the karaoke which can be connected in front of a karaoke machine for the tone-turning treatment for the accompanying music. The utility model comprises a connecting key group and a controlled frequency shift circuit designed by the principle of the single sideband modulation demodulation. A corresponding parameter is set for producing a square wave with the frequency f (1) through the key group state which is operated according to the modulation requirements and is read-in by an SCM. After filtering, the amplitude of the accompanying music signals is modulated to the f (1) through a multiplier. The modulated signals are filtered into single sideband signals with a certain frequency difference through a wave filter whose cutoff frequency is the f (1). The SCM and the band pass filter thereof produce f (2) demodulation carrier signals. The single sideband signals are demodulated by the multiplier. Thus, frequency-shift signals can be obtained after filtering.

Description

Tone turning device for karaoke

The utility model relates to a kind of electronic musical instrument, relates to a kind of karaoke machine transposition device or rather.

Karaoke uses the accompaniment music program band of prerecording to sing, owing to adopt the vocal accompaniment band of prerecording, thereby the tone of corresponding every song all is changeless, yet singer's singing voice range is different, the often suitable song of singing different tones of different people, therefore such situation usually takes place: many songs of originally liking even being good at, when using karaoke, unsatisfactory, thereby overslaugh further popularizing of karaoke machine, improve, reduced its effect that should bring into play.

The purpose of this utility model is exactly a kind of novel vocal accompaniment functional extender apparatus at the problems referred to above design, it is the transposition device of karaoke machine, be plugged on before the existing karaoke machine, to vocal accompaniment music from audiogenic devices such as sound-track engraving apparatus, video recorders, handle according to the modified tone that the singer requires to carry out rising tune or falling tone, be sent to karaoke machine again.

The utility model design concept is to read in the key groups state by controlled shift frequency circuit, according to the key groups input state accompaniment signal is carried out corresponding frequency displacement again and handles, the vocal accompaniment music behind the output shift frequency.

Controlled shift frequency circuit of the present utility model with single-sideband modulation demodulation method principle design, will be imported the accompaniment signal amplitude modulation(PAM) earlier to certain high-frequency signal, behind the monolateral band of its low side of low-pass filter elimination, be demodulated to desirable value by the frequency signal of setting again.

There is Single Chip Microcomputer (SCM) system to comprise 51 series monolithics and supporting ROM, read in the input state of key groups, determine relevant parameter by program according to the key groups state, the generation frequency is F(1) square-wave signal, be filtered into sinusoidal signal and amplification through active low-pass filter, send the VY end of the 1st multiplier, as modulated carrier signal; The Vx end input vocal accompaniment music signal of first multiplier, the 1st multiplier output is subjected to tonal signal to cutoff frequency to be fixed as F(2) Hi-pass filter, elimination is subjected to the lower frequency composition of tonal signal, or for the single sideband singal that certain frequency difference arranged adds to the VX end of the 2nd multiplier, F(1) with F(2) difference corresponding with the transposition requirement; Having the stabilized frequency generator to send fixed-frequency is F(2) the stable solution adjusting carrier signal add to the VY end of the 2nd multiplier, with the 2nd multiplier the single sideband singal that certain frequency difference is arranged is carried out demodulation, the output restituted signal is removed clutter through low-pass filter, and the sinusoidal signal of output is the accompaniment signal after the transposition.

Describe technology of the present utility model in detail below in conjunction with the embodiment accompanying drawing

Fig. 1 karaoke machine transposition device theory diagram

Fig. 1 karaoke machine transposition device circuit structure diagram

Fig. 1 karaoke machine transposition device Single Chip Microcomputer (SCM) system software block diagram

The supporting use synoptic diagram of Fig. 1 karaoke machine transposition device and karaoke machine

Referring to Fig. 1,1 is key groups among the figure, and 2 is Single Chip Microcomputer (SCM) system, and 3,8 are respectively the 1st, the 2nd low-pass filter, and 4,6 are respectively the 1st, the 2nd multiplier, and 5 is Hi-pass filter, and 7 is the stabilized frequency generator.Accompaniment signal A imports the VX end of the 1st multiplier 4, accompaniment signal B behind the shift frequency is by 8 outputs of the 2nd low-pass filter, Single Chip Microcomputer (SCM) system 2 is according to the key position setting state relevant parameter of key groups 1, the generation frequency is f(1) square-wave signal, after active low-pass filter 3 filtering are amplified as modulated carrier signal.Be subjected to tonal signal to be fixed as f(2 through cutoff frequency) its lower frequency composition of Hi-pass filter 5 eliminations, become and the corresponding single sideband singal that certain frequency difference is arranged of transposition requirement.It is f(2 that stabilized frequency generator 7 sends frequency) the stable solution adjusting carrier signal, 6 pairs of multipliers have the single sideband singal of certain frequency difference to carry out demodulation, export through low-pass filter 8 filtering again.

Key groups 1 can be made into the touch-switch type according to the subject of a sale, knob (digital encoder) type and infrared remote control type.

Referring to accompanying drawing 2, circuit structure shown in Figure 2 designs by Fig. 1 theory diagram, RM1, RM2, SW0, SW+, SW-, D1, D2, D3 constitute key groups 1, by rising tune, falling tone, invariable tone switch SW+, SW-, SW0 input transposition order, show rising tune, falling tone, invariable tone state by light emitting diode D3, D1, D2, when pressing SW+, D3 is bright, and the expression music of will accompanying is moved to lofty tone; When pressing SW-, D1 is bright, and the expression music of will accompanying is moved toward low-key; When pressing SW0, D2 is bright, and expression keeps the tone of former vocal accompaniment music, and whenever by a SW+, tune rises one-level, and whenever by a SW-, one-level falls in tune.When the number of times of pressing the SW+ key when pressing the number of times of SW-key, unclamp button, D3 is bright, the vocal accompaniment music is heightened than the vocal accompaniment note of input after the modified tone of expression output; Otherwise D1 is bright, and the vocal accompaniment music is turned down than the vocal accompaniment note of input after the modified tone of expression output; The bright expression of D2 SW+, SW-touch potential equate that former vocal accompaniment music melody is constant.The effect of capacitor C 1 is when start among the figure, make circuit have the auto-reset function of powering on, thereby the assurance Single Chip Microcomputer (SCM) system is normally moved.

Constitute 51 Single Chip Microcomputer (SCM) system 2 by U1, U2, U3, embodiment U1 adopts 8031 central processing units, and its X1, X2 termination have capacitor C 2, C3 and crystal oscillator XTAL, U2 adopts eight D-latch 74LS373, U3 adopts 8K * 8 EPROM2764, and 21 is data bus among the figure, and 22 is address bus.

In conjunction with Single Chip Microcomputer (SCM) system software block diagram shown in Figure 3, Single Chip Microcomputer (SCM) system is according to designed program, constantly read in the key groups state, judge and light D1 or D2 or D3, and transfer to require to calculate relevant parameter according to ascending, descending, reset timer, by the bidirectional port of U1 such as P1.0 end output respective frequencies square wave f(1) make modulating signal source, the square wave f(1 that is produced) frequency and fixed frequency f(2) difference and transposition require corresponding, simultaneously by another bidirectional port such as the P1.1 end output fixed frequency square wave f(2 of U1) call for separating.

Among Fig. 2, constitute active low-pass filter 3 by U4A, R1-R3, C4, C5, constitute bandpass filter by U4B, R12, R13, C10, C11, the f(1 that P1.0, the P1.1 of U1 end is sent respectively), f(2) the two-way square-wave signal is filtered into sinusoidal signal, bandpass filter also has the frequency stabilization effect, and the effect of single-chip microcomputer U1 and the logical filter U4B of band etc. is equivalent to the stabilized frequency generator 7 in Fig. 1 theory diagram.

Constitute the 1st analog multiplier 4 by U5, R4-R9, C6, C17, U5 adopts linear four-quadrant multiplier MC1595L, socket J-IN input vocal accompaniment music signal A also adds to multiplier VX end, its VY end input be modulated carrier f(1) sinusoidal signal, finish audio signal A to f(1) modulation.

Constituting cutoff frequency by U4C, R10, R11, C7, C8, C9 is f(2) active high-pass filter 5, elimination is subjected to the monolateral band portion of the low side of tonal signal, becomes the single sideband singal that certain frequency difference is arranged.

Constitute the 2nd analog multiplier 6 by U6, R14-R19, C12, C13, U6 also adopts linear four limits to resemble multiplier MC1595L, and single sideband singal is carried out demodulation.

U4D, R20-R22, C14-C16 constitute active low-pass filter 8, elimination clutter, the vocal accompaniment music B after the socket J-out output transposition.

Embodiment U4A, U4B, U4C, U4D adopt four-operational amplifier LF347.

Referring to accompanying

drawing

4,10 is audiogenic devices such as video recorder, sound-track engraving apparatus among the figure, and output has the vocal accompaniment music of specific tone, after Karaoke transposition device 20 of the present utility model modifies tone, import karaoke machine 30 again, export by loudspeaker after handling through mixing etc. with singer's sound (MIC).

The utility model is simple in structure, with low cost, make to transfer and survey easily, be the vocal accompaniment functional extender apparatus of karaoke machine, can be widely used in karaoke halls, unit, the family, the activity of tissue Karaoke sing-in, can be according to singer's range, the vocal accompaniment music is carried out the ascending, descending modulationization,, improve singing effect as transferring Qu Gaiwei C to transfer song etc. original G.

Claims

1, a kind of karaoke machine transposition device comprises by the key groups and the controlled shift frequency circuit of transposition requirement operation, it is characterized in that described controlled shift frequency circuit comprises:

1) Single Chip Microcomputer (SCM) system is arranged, comprise 51 series monolithics and supporting ROM, described key groups is connected with single-chip microcomputer, and any end output of single-chip microcomputer bidirectional port requires f (1) frequency square-wave signal to the 1 active low-pass filter of variation with transposition;

2) the 1st multiplier is arranged, the vocal accompaniment music signal of its Vx termination input, the output of its Vy termination the 1st active low-pass filter, the output of the 1st multiplier connects the Hi-pass filter that cutoff frequency is f (2), and the output of high pass filter connects the 2nd multiplier Vx end;

3) the stabilized frequency generator is arranged, produce f (2) fixed frequency signal and export the 2nd multiplier Vy end to, the output of the 2nd multiplier connects the 2nd low-pass filter, the vocal accompaniment music signal that the output of the 2nd low-pass filter is handled through transposition.

2, a kind of karaoke machine transposition device according to claim 1 is characterized in that described stabilized frequency generator is by another arbitrary end of single-chip microcomputer bidirectional port output f(2) fixedly square wave frequency to bandpass filter form.