CN108540905B - Frequency divider circuit and frequency divider - Google Patents
Frequency divider circuit and frequency divider Download PDFInfo
- Publication number
- CN108540905B CN108540905B CN201810457404.1A CN201810457404A CN108540905B CN 108540905 B CN108540905 B CN 108540905B CN 201810457404 A CN201810457404 A CN 201810457404A CN 108540905 B CN108540905 B CN 108540905B
- Authority
- CN
- China
- Prior art keywords
- filter
- pass filter
- unit
- low
- input end
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R3/00—Circuits for transducers, loudspeakers or microphones
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R2430/00—Signal processing covered by H04R, not provided for in its groups
Abstract
The invention relates to a frequency divider circuit and a frequency divider, wherein the built-in frequency divider circuit can provide a relatively flat amplitude response in a full-frequency-domain loudspeaker system combined by two loudspeaker units, and can control the phase difference of a first filter unit and a second filter unit within a preset phase difference range within an effective sound reproduction frequency range. Based on the method, the sound phase difference of the high and low voice loudspeaker units tends to be zero and linear, the sound of the high and low voice loudspeaker units is fused into a sound source, and the sound tone quality level of the full-frequency-range loudspeaker system is improved.
Description
Technical Field
The present invention relates to the field of sound system technology, and in particular, to a frequency divider circuit and a frequency divider.
Background
A sound system consisting of several loudspeakers with different effective operating frequency ranges is generally provided with a frequency divider. The frequency divider has two forms of passive frequency division and active frequency division. The frequency divider can divide one sound source signal into two or more output signals, the output signals are transmitted to the corresponding audio power amplifiers according to the output signals, and the audio power amplifiers are driven to produce sound after power amplification.
The traditional way of measuring the performance of a full-frequency-range speaker system is mainly to measure the amplitude-frequency characteristics of sounds in different frequency ranges in the full-frequency-range speaker system and to measure the sound quality of a sound according to the amplitude-frequency characteristics. Therefore, the traditional full-frequency-range speaker system designed based on the crossover network mainly focuses on the design of the amplitude-frequency characteristic, pursues the flatness of the amplitude-frequency characteristic of the full-frequency range, and focuses on avoiding distortion caused by uneven amplitude-frequency response.
However, since any single speaker cannot perfectly reproduce the sound in each frequency band completely, the conventional full-band speaker system lacks design considerations of the phase-frequency characteristics of the units in different effective operating frequency ranges, which causes a large phase difference between the output signals of the units in different effective operating frequency ranges, affects the amplitude-frequency characteristics and the phase characteristics of each sub-harmonic of the output signals of the full-band speaker system, and affects the sound quality of the output sound of the full-band speaker system.
Disclosure of Invention
In view of the above, it is necessary to provide a frequency divider circuit and a frequency divider for solving the problem of the conventional sound system design that lacks design considerations of phase-frequency characteristics of different effective operating frequency range units.
The technical scheme provided by the embodiment of the invention is as follows:
a frequency divider circuit includes a first filter unit and a second filter unit;
the input end of the first filter unit and the input end of the second filter unit are used for inputting the same sound source signal;
the output end of the first filter unit is used for being connected with the input end of an audio power amplifier of the high pitch loudspeaker unit and driving the high pitch loudspeaker unit after power amplification;
the output end of the second filter unit is used for being connected with the input end of an audio power amplifier of the woofer unit and driving the woofer unit after power amplification;
and the phase difference between the output signal of the first filter unit and the output signal of the second filter unit is less than or equal to a preset phase difference.
In an alternative embodiment, the first filter unit comprises a first high-pass filter and a second high-pass filter;
the output end of the first high-pass filter is connected with the input end of the second high-pass filter; the input end of the first high-pass filter is the input end of the first filter unit, and the output end of the second high-pass filter is the output end of the first filter unit.
In an alternative embodiment, the second filter unit comprises a first low-pass filter and a second low-pass filter;
the output end of the first low-pass filter is connected with the input end of the second low-pass filter; the input end of the first low-pass filter is the input end of the second filter unit, and the output end of the second low-pass filter is the output end of the second filter unit.
In an alternative embodiment, the first high-pass filter, the second high-pass filter, the first low-pass filter, and the second low-pass filter are all linkoviz-rayleigh filters.
In an optional embodiment, the first high-pass filter and the second high-pass filter each include an operational amplifier, a feedback resistor, a filter resistor, a first filter capacitor, and a second filter capacitor;
one end of the first decoupling capacitor is the input end of the first high-pass filter and the second high-pass filter, the other end of the first decoupling capacitor is connected with one end of the second decoupling capacitor, and the other end of the second decoupling capacitor is connected with the non-inverting input end of the operational amplifier;
the non-inverting input end of the operational amplifier is grounded through a filter resistor;
the output end of the operational amplifier is connected with the inverting input end of the operational amplifier;
the output end and the inverting input end of the operational amplifier are both connected with the other end of the first filter capacitor through a feedback resistor;
the output end of the operational amplifier is the output end of the first high-pass filter and the second high-pass filter.
In an optional embodiment, each of the first low-pass filter and the second low-pass filter includes an operational amplifier, a feedback capacitor, a filter capacitor, a first filter resistor, and a second filter resistor;
one end of the first filter resistor is the input end of the first low-pass filter and the second low-pass filter, the other end of the first filter resistor is connected with one end of the second filter resistor, and the other end of the second filter resistor is connected with the non-inverting input end of the operational amplifier;
the non-inverting input end of the operational amplifier is grounded through a filter capacitor;
the output end of the operational amplifier is connected with the inverting input end of the operational amplifier;
the output end and the inverting input end of the operational amplifier are both connected with the other end of the first filter resistor through a feedback capacitor;
the output end of the operational amplifier is the output end of the first low-pass filter and the second low-pass filter.
In an alternative embodiment, a third high pass filter is further included;
the output end of the third high-pass filter is respectively connected with the input end of the first filter unit and the input end of the second filter unit;
the input end of the third high-pass filter is used for inputting the sound source signal. The third high-pass filter is used for filtering the second low-frequency signal of the input sound source signal.
In an optional embodiment, the system further comprises a frequency response equalization circuit;
the output end of the frequency response equalizing circuit is connected with the input end of the third high-pass filter;
the input end of the equalization circuit is used for inputting sound source signals.
The frequency divider circuit provided by the embodiment of the invention is matched with a corresponding audio power amplifier. A relatively flat amplitude response can be provided in a near full range loudspeaker system in which two loudspeaker units (a treble unit and a bass unit) are combined, and the phase difference between the first filter unit and the second filter unit can be controlled within a predetermined phase difference range over an effective sound reproduction frequency range. Based on the method, the sounding phase difference of the high and low voice loudspeaker units tends to zero, the sounds of the high and low voice loudspeaker units are integrated into a sound source, and the sound tone quality level of a full-frequency-range loudspeaker system is improved.
The embodiment of the invention also provides a frequency divider, which comprises a frequency divider shell and a frequency divider circuit arranged in the frequency divider shell.
According to the frequency divider provided by the embodiment of the invention, the built-in frequency divider circuit can provide a relatively flat amplitude response in a full-frequency-range loudspeaker system combined by two loudspeaker units, and the phase difference of the first filter unit and the second filter unit can be controlled within a preset phase difference range within an effective sound reproduction frequency range. Based on the method, the sound phase difference of the high and low voice loudspeaker units tends to zero, the sound of the high and low voice loudspeaker units is fused into a sound source, and the sound tone quality level of the full-frequency-range loudspeaker system is improved.
The embodiment of the invention also provides a two-tone audio system, which comprises a high pitch loudspeaker unit, an audio power amplifier corresponding to the high pitch loudspeaker unit, a low pitch loudspeaker unit, an audio power amplifier corresponding to the low pitch loudspeaker unit and a frequency divider circuit;
the output end of the first filter unit is used for being connected with the input end of an audio power amplifier of the high pitch loudspeaker unit and driving the high pitch loudspeaker unit after power amplification;
the output end of the second filter unit is used for connecting the input end of an audio power amplifier of the woofer unit and driving the woofer unit after power amplification;
in the two-tone audio system provided by the embodiment of the invention, the sound source signal is transmitted to the frequency divider circuit, the built-in frequency divider circuit processes the sound source signal into two paths of output signals, the two paths of output signals are subjected to power amplification by the corresponding audio power amplifier and then drive the high pitch loudspeaker unit and the low pitch loudspeaker unit respectively, and the phase difference of the sound of the high pitch loudspeaker unit and the sound of the low pitch loudspeaker unit is controlled within a preset phase difference range. Based on the above, the sound phase difference of the high and low tone loudspeaker units tends to zero, and the sound of the high and low tone units is fused into one sound source, thereby improving the sound quality level of the two frequency division sound system.
Drawings
FIG. 1 is a block diagram of a divider circuit according to an embodiment;
fig. 2 is a schematic connection diagram of a circuit module of a frequency divider according to a second embodiment;
FIG. 3 is a schematic circuit diagram of the first high-pass filter or the second high-pass filter;
FIG. 4 is a schematic diagram of an internal circuit structure of the first filter unit;
FIG. 5 is a schematic diagram of a circuit structure of the first low-pass filter or the second low-pass filter;
FIG. 6 is a schematic diagram of an internal circuit structure of the second filter unit;
FIG. 7 is a circuit diagram of a frequency divider;
FIG. 8 is a phase difference plot based on a specific circuit;
FIG. 9 is a schematic diagram of a frequency divider circuit block connection according to an alternative embodiment;
FIG. 10 is a schematic diagram of another alternative embodiment of a divider circuit block connection;
FIG. 11 is a circuit diagram of a frequency divider according to an exemplary embodiment;
FIG. 12 is a schematic diagram of a frequency divider according to a fourth embodiment;
fig. 13 is a schematic block diagram of a two-tone audio system according to a fifth embodiment.
Detailed Description
For better understanding of the objects, technical solutions and effects of the present invention, the present invention will be further explained with reference to the accompanying drawings and examples. Meanwhile, the following described examples are only for explaining the present invention, and are not intended to limit the present invention.
Example one
Fig. 1 is a schematic block connection diagram of a frequency divider circuit according to an embodiment, and as shown in fig. 1, the frequency divider circuit includes a first filter unit 100 and a second filter unit 101;
the input end Vi (h) of the first filter unit 100 and the input end Vi (l) of the second filter unit 101 are both used for inputting the same sound source signal Vi;
after first filter section 100 and second filter section 101 receive sound source signal Vi, first filter section 100 and second filter section 101 filter sound source signal Vi independently. The first filter unit 100 is configured to separate a treble band from the sound source signal Vi, and the second filter unit 101 is configured to separate a bass band from the sound source signal Vi.
The output end vo (h) of the first filter unit 100 is used for connecting an input end of an audio power amplifier of the tweeter unit, and drives the tweeter unit after power amplification, so that an output signal of the first filter unit 100 is transmitted to the tweeter unit;
the output signal of the first filter unit 100 is the high-pitch frequency band of the sound source signal Vi, and the high-pitch speaker unit is a speaker for correspondingly playing the high-pitch frequency band of the sound source signal Vi.
The output end vo (l) of the second filter unit 101 is used for connecting an input end of an audio power amplifier of the woofer unit, and driving the tweeter unit after power amplification, so that an output signal of the second filter unit 101 is transmitted to the woofer unit;
the output signal of the second filter unit 101 is a bass portion of the sound source signal Vi, and the woofer unit is a speaker that correspondingly plays a bass frequency segment of the sound source signal Vi.
The phase difference between the output signal of the first filter unit 100 and the output signal of the second filter unit 101 is less than or equal to a preset phase difference.
Wherein the preset phase difference is less than 45 degrees, preferably less than 15 degrees.
The divider circuit according to the first embodiment can provide a relatively flat amplitude response in a near-full-frequency-range speaker system combined by two speaker units, and can control the phase difference between the first filter unit 100 and the second filter unit 101 within a predetermined phase difference range within an effective sound-reproduction frequency range. Based on the method, the sound phase difference of the high and low voice loudspeaker units tends to zero, the sound of the high and low voice loudspeaker units is fused into a sound source, and the sound quality level of the full-frequency-range loudspeaker system is improved.
Example two
Fig. 2 is a schematic diagram illustrating the connection of circuit blocks of a frequency divider according to a second embodiment, and as shown in fig. 2, the first filter unit 100 includes a first high-pass filter 1000 and a second high-pass filter 1001;
the output Vo1 of the first high-pass filter 1000 is connected to the input Vi2 of the second high-pass filter 1001; wherein the input Vi1 of the first high-pass filter 1000 is the input Vi (h) of the first filter unit 100, and the output Vo2 of the second high-pass filter 1001 is the output Vo (h) of the first filter unit 100.
The first high-pass filter 1000 and the second high-pass filter 1001 are both high-pass active filters, and the frequency dividing points of the first high-pass filter 1000 and the second high-pass filter 1001 are the same. Optionally, the high-pass active filter is a-12 dB/oct Linkwitz-Riley Linkwitz-rayleigh filter, a Bessel filter, and a Butterworth filter, and two-12 dB/oct filters are connected in series to form a-24 dB/oct filter.
As shown in fig. 2, the second filter unit 101 includes a first low-pass filter 1010 and a second low-pass filter 1011;
the output Vo3 of the first low-pass filter 1010 is connected to the input Vi4 of the second low-pass filter 1011; wherein the input Vi3 of the first low-pass filter 1010 is the input Vi (l) of the second filter unit 101 and the output Vo4 of the second low-pass filter 1011 is the output Vo (l) of the second filter unit 101.
The first low-pass filter 1010 and the second low-pass filter 1011 are both low-pass active filters, and the frequency dividing points of the first low-pass filter 1010 and the second low-pass filter 1011 are the same. Optionally, the low-pass active filter is a-12 dB/oct Linkwitz-Riley Linkwitz-rayleigh filter, a Bessel filter, and a Butterworth filter, and two-12 dB/oct filters are connected in series to form a-24 dB/oct filter.
In an optional embodiment, the frequency dividing points of the first high-pass filter 1000, the second high-pass filter 1001, the first low-pass filter 1010 and the second low-pass filter 1011 are the same, and all of them are a Linkwitz-Riley Linkwitz-rayleigh filter, a Bessel filter and a Butterworth filters of-12 dB/oct, so that the best isolation is obtained between the first filter unit 100 and the second filter unit 101, and phase fusion is realized under the condition that the maximum flat amplitude-frequency response is obtained, and meanwhile, based on insensitivity to the speaker unit, the phase difference between the output signal of the first filter unit 100 and the output signal of the second filter unit 101 tends to zero and linear, so that the sound of the high-pitch speaker unit and the sound of the low-pitch speaker unit merge into one sound source.
In an alternative embodiment, the first high pass filter 1000, the second high pass filter 1001, the first low pass filter 1010, and the second low pass filter 1011 are all-12 dB/oct Linkwitz-Riley linkoviz-Rayleigh filters, Bessel filters, Butterworth filters. The phase difference obtained by a-12 dB/oct LINKEVIZE-Rayleigh high-pass and low-pass filter (the high pitch unit needs to be connected in a reverse way) or a-24 dB/oct LINKEVIZE-Rayleigh high-pass and low-pass filter is close to zero. In practical applications, filters with different attenuation slopes may be selected according to the frequency response of the tweeter unit or the woofer unit. Wherein, when the filter of-12 dB/oct is selected, the tweeter units need to be connected in reverse to obtain a phase difference approaching zero.
EXAMPLE III
Fig. 3 is a schematic circuit structure diagram of the first high-pass filter or the second high-pass filter, and as shown in fig. 3, each of the first high-pass filter 1000 and the second high-pass filter 1001 includes an operational amplifier Uh, a feedback resistor Rf, a filter resistor Rgnd, a first filter capacitor CP1, and a second filter capacitor CP 2;
one end of the first filter capacitor CP1 is the input ends (Vi1 and Vi2) of the first high-pass filter 1000 and the second high-pass filter 1001, the other end is connected with one end of the second filter capacitor CP2, and the other end of the second filter capacitor CP2 is connected with the non-inverting input end of the operational amplifier Uh;
the non-inverting input end of the operational amplifier Uh is grounded through a bias resistor and a filter resistor Rgnd;
the output end of the operational amplifier Uh is connected with the inverting input end of the operational amplifier Uh;
the output end and the inverting input end of the operational amplifier Uh are both connected with the other end of the first filter capacitor CP1 through a feedback resistor Rf;
the outputs of the operational amplifier Uh are the outputs 1001(Vo1 and Vo2) of the first and second high- pass filters 1000 and 1001.
Fig. 4 is a schematic diagram of an internal circuit structure of the first filter unit, and as shown in fig. 4, an output terminal of the operational amplifier Uh in the first high-pass filter 1000 is connected to one end of the first filter capacitor in the second high-pass filter 1001, so that the first high-pass filter 1000 and the second high-pass filter 1001 are connected in series.
Fig. 5 is a schematic circuit structure diagram of the first low-pass filter or the second low-pass filter, and as shown in fig. 5, each of the first low-pass filter 1010 and the second low-pass filter 1011 includes an operational amplifier Ul, a feedback capacitor Cf, a filter capacitor Cgnd, a first filter resistor RP1, and a second filter resistor RP 2;
one end of the first filter resistor RP1 is an input end (Vi3 and Vi4) of the first low-pass filter and the second low-pass filter, the other end is connected with one end of the second filter resistor RP2, and the other end of the second filter resistor RP2 is connected with a non-inverting input end of the operational amplifier Ul;
the non-inverting input end of the operational amplifier Ul is grounded through a filter capacitor Cgnd;
the output end of the operational amplifier Ul is connected with the inverting input end of the operational amplifier Ul;
the output end and the inverting input end of the operational amplifier Ul are both connected with the other end of the first filter resistor RP1 through a feedback capacitor Cf;
the output terminals of the operational amplifier Ul are the output terminals (Vo3 and Vo4) of the first low-pass filter 1010 and the second low-pass filter 1011.
Fig. 6 is a schematic diagram of an internal circuit structure of the second filter unit, and as shown in fig. 6, an output terminal of the operational amplifier Ul in the first low-pass filter 1010 is connected to one end of the first filter resistor RP1 in the second low-pass filter 1011, so that the first low-pass filter 1010 and the second low-pass filter 1011 are connected in series.
The third technical solution of the embodiment provides a specific circuit of the first high-pass filter, the second high-pass filter, the first low-pass filter and the second low-pass filter. This circuit effectively reduces the phase difference between the output signal of first filter section 100 and the output signal of second filter section 101, and improves the overall sound quality of the high and low tone speaker units.
Fig. 7 is a circuit diagram of a frequency divider, and as shown in fig. 7, the specific circuit provided in fig. 7 is based on the schematic diagram of the internal circuit structure of the first filter unit shown in fig. 3 in the third implementation and the schematic diagram of the internal circuit structure of the second filter unit shown in fig. 6, and performs specific device parameter selection. The specific devices in fig. 7 are preferably selected as follows:
the operational amplifier Uh and the operational amplifier Ul can be universal operational amplifiers such as UPC 4558; the feedback resistor Rf is a resistor with the resistance value of 2.558k omega; the filter resistor Rgnd selects a resistor with the resistance value of 5.114k omega; the first decoupling capacitor CP1 and the second decoupling capacitor CP2 both adopt capacitors with the capacitance value of 22 nF; the feedback capacitor Cf is a capacitor with a capacitance value of 56.26 nF; the filter capacitor Cgnd is a capacitor with a capacitance value of 28.13 nF; the first filter resistor RP1 and the second filter resistor RP2 both adopt resistors with the resistance value of 2k omega. The positive power ends of the operational amplifier Uh and the operational amplifier Ul are connected with a positive 15V power supply, and the negative power ends are connected with a negative 15V power supply.
It should be noted that the selection of the device is a selected value based on the circuit and device arrangement of fig. 7, rather than the only selected value, and as an example, the optimal phase difference characteristic can be realized based on a selected value of the circuit and device arrangement of fig. 7. The floating selection of the device in actual use based on the above selection values is still within the scope of the embodiments of the present invention.
Fig. 8 is a phase difference graph based on a specific circuit, wherein the abscissa of the graph is frequency/Hz and the ordinate is phase difference/degree. In the circuit selected based on the specific circuit shown in fig. 7 and the specific devices described above, the phase difference between the output signal of the first filter unit 100 and the output signal of the second filter unit 101 is as shown in fig. 8, and the phase difference tends to zero in the approximate range of frequencies 500Hz to 8 kHz. The correspondence between the phase difference and the frequency shown in fig. 8 is shown in table 1 (phase curve test data table):
TABLE 1 phase curve test data sheet
As can be seen from the above table, the left channel corresponds to the phase of the output signal of the first filtering unit 100, the right channel corresponds to the phase of the output signal of the second filtering unit 101, and the phase difference is the phase difference, unit/degree, between the output signal of the first filtering unit 100 and the output signal of the second filtering unit 101. In the range of 500Hz to 8kHz, the phase difference does not exceed 15 degrees. In the conventional two-frequency divider, the phase difference is basically greater than 45 degrees. In practical tests, the inventor respectively tests 40 frequency divider circuit samples, and within the range of 500Hz to 8kHz, the phase difference obtained by the tests does not exceed 15 degrees, the phase difference of partial samples is less than 10 degrees, and the phase difference of individual samples is less than 5 degrees. Not to be listed herein, but to the extent. Therefore, the frequency divider circuit provided by the embodiment of the invention can effectively reduce the phase difference.
Fig. 9 is a schematic diagram of a connection of a frequency divider circuit module according to an alternative embodiment, as shown in fig. 9, the frequency divider circuit further includes a third high-pass filter 201;
the output end of the third high-pass filter 201 is connected to the input end vi (h) of the first filter unit 100 and the input end vi (l) of the second filter unit 101, respectively;
the input end of the third high-pass filter is used for inputting sound source signals and filtering the second low-frequency signals in the sound source signals.
The frequency divider circuit according to this alternative embodiment helps further reduce the phase difference between the output signal of first filter section 100 and the output signal of second filter section 101 by reducing the interference in the sound source signal by third high-pass filter 201.
Fig. 10 is a schematic diagram of a connection of a frequency divider circuit block according to another alternative embodiment, as shown in fig. 10, the frequency divider circuit further includes a frequency response equalization circuit 301;
wherein, the frequency response equalizing circuit 301 can select an equalizer.
The output end of the frequency response equalizing circuit 301 is connected with the input end of the third high-pass filter 201;
the input of the frequency response equalizer 301 is used for inputting the audio source signal.
The frequency divider circuit according to this alternative embodiment compensates and modifies the sound source signal by the frequency response equalizer circuit 301, and helps further reduce the phase difference between the output signal of the first filter unit 100 and the output signal of the second filter unit 101.
Fig. 11 is a circuit diagram of a frequency divider according to a specific application example, and as shown in fig. 11, the third high-pass filter 201 includes an operational amplifier U1, a pre-resistor R1, a filter resistor R2, and a filter capacitor C1. The output of the operational amplifier U1 is connected to its inverting input and to the input vi (h) of the first filter unit 100 and to the input vi (l) of the second filter unit, respectively; the non-inverting input terminal of the operational amplifier U1 is grounded through the filter resistor R2 and the filter capacitor C1 in sequence, and is connected to the output terminal of the frequency response equalizing circuit 301 through the pre-resistor R1.
In the specific device type selection, the operational amplifier U1 can be a universal operational amplifier such as UPC4558, the pre-resistor R1 can be a resistor with a resistance of 47k Ω, the filter resistor can be a resistor with a resistance of 30k Ω, and the filter capacitor can be a capacitor with a capacitance of 27 nF. The selection of the devices is an ideal value based on the circuit and device collocation of fig. 7 to achieve the optimal phase difference characteristic. In actual use, the floating selection of the device based on the above selection values is still within the protection scope of the embodiment of the present invention.
The frequency response equalizing circuit 301 includes an operational amplifier U2, a filter resistor R3, a feedback resistor R4, a first filter capacitor C2, and a second filter capacitor C3. One end of the first filter capacitor C2 is used for accessing an audio source signal, the other end of the first filter capacitor C2 is connected with one end of the second filter capacitor C3, and the other end of the second filter capacitor C3526 is connected with the non-inverting input end of the operational amplifier U2; the non-inverting input end of the operational amplifier U2 is grounded through a filter resistor R3; the output end of the operational amplifier U2 is connected with the inverting input end of the operational amplifier U2; the output end and the inverting input end of the operational amplifier U2 are both connected with the other end of the first filter capacitor C2 through a feedback resistor R4; the output of the operational amplifier U2 is the output of the frequency response equalization circuit.
In the specific device type selection, the operational amplifier U2 may be a UPC 4558-class general operational amplifier, the filter resistor R3 may be a resistor with a resistance of 51k Ω, the feedback resistor may be a resistor with a resistance of 27k Ω, and the first filter capacitor C2 and the second filter capacitor C3 may be capacitors with a capacitance of 220 nF. The selection of the devices is an ideal value based on the circuit and device collocation of fig. 7 to achieve the optimal phase difference characteristic. In actual use, the floating selection of the device based on the above selection values is still within the protection scope of the embodiment of the present invention.
Example four
Fig. 12 is a schematic diagram of a frequency divider according to a fourth embodiment, and as shown in fig. 12, the frequency divider includes a frequency divider housing 400 and a frequency divider circuit 401 according to first to third embodiments, which is disposed in the frequency divider housing.
The divider circuit 401 provided in the fourth embodiment can provide a relatively flat amplitude response in a near-full-band speaker system combined by two speaker units, and can control the phase difference between the first filter unit and the second filter unit within a preset phase difference range within an effective sound reproduction frequency range. Based on the method, the sound phase difference of the high and low voice loudspeaker units tends to be zero and linear, the sound of the high and low voice loudspeaker units is fused into a sound source, and the sound tone quality level of the full-frequency-range loudspeaker system is improved.
EXAMPLE five
Fig. 13 is a block diagram of a two-tone audio system according to a fifth embodiment, as shown in fig. 13, including a tweeter unit 501, a woofer unit 502, a crossover circuit 503, an audio power amplifier 504 of the corresponding tweeter unit, and an audio power amplifier 505 of the corresponding woofer unit;
the output end vo (h) of the first filter unit 100 is used for connecting the audio power amplifier 504, and the output signal of the first filter unit 100 is amplified by the audio power amplifier 504 and then transmitted to the audio speaker unit 501;
the output vo (l) of the second filter unit 101 is used to connect to the audio power amplifier 505, and the output signal of the second filter unit 101 is amplified by the audio power amplifier 505 and then transmitted to the woofer unit 502.
In the two-tone audio system provided in the fifth embodiment, the sound source signal is transmitted to the frequency divider circuit 503, the built-in frequency divider circuit processes the sound source signal into two output signals, and the tweeter unit 501 and the woofer unit 502 are respectively driven by the audio power amplifier circuit, so that the phase difference between the sounds of the tweeter unit 501 and the woofer unit 502 is controlled within the preset phase difference range. Based on the above, the sound phase difference of the high and low tone loudspeaker units tends to zero and linear, the sound of the high and low tone units is integrated into one sound source, and the sound tone quality level of the two frequency division sound system is improved.
The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above examples only show some embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (5)
1. A frequency divider circuit comprising a first filter unit and a second filter unit;
the first filter unit comprises a first high-pass filter and a second high-pass filter, and the output end of the first high-pass filter is connected with the input end of the second high-pass filter;
the second filter unit comprises a first low-pass filter and a second low-pass filter, and the output end of the first low-pass filter is connected with the input end of the second low-pass filter;
the input end of the first high-pass filter and the input end of the first low-pass filter are both used for inputting the same sound source signal;
the output end of the second high-pass filter is used for being connected with the input end of an audio power amplifier of the high pitch loudspeaker unit and driving the high pitch loudspeaker unit after power amplification;
the output end of the second low-pass filter is used for being connected with the input end of an audio power amplifier of the woofer unit and driving the woofer unit after power amplification;
wherein the first high-pass filter, the second high-pass filter, the first low-pass filter and the second low-pass filter are all-12 dB/oct of a Lenkviz Rayleigh filter or a Butterworth filter, frequency dividing points of the first high-pass filter, the second high-pass filter, the first low-pass filter and the second low-pass filter are the same, and a phase difference between an output signal of the first filter unit and an output signal of the second filter unit is not more than 15 degrees in a range of 500Hz to 8 kHz;
the first high-pass filter and the second high-pass filter both comprise an operational amplifier Uh, a filter feedback resistor, a filter resistor Rgnd, a first filter capacitor CP1 and a second filter capacitor CP 2;
one end of the first filter capacitor CP1 is an input end of the first high-pass filter and the second high-pass filter, the other end of the first filter capacitor CP1 is connected to one end of the second filter capacitor CP2, and the other end of the second filter capacitor CP2 is connected to a non-inverting input end of the operational amplifier Uh;
the non-inverting input end of the operational amplifier Uh is grounded through the filter resistor Rgnd;
the output end of the operational amplifier Uh is connected with the inverting input end of the operational amplifier Uh;
the output end and the inverting input end of the operational amplifier Uh are both connected with the other end of the first filter capacitor CP1 through the feedback resistor;
the output end of the operational amplifier Uh is the output ends of the first high-pass filter and the second high-pass filter;
the first low-pass filter and the second low-pass filter each comprise an operational amplifier Ul, a feedback capacitor, a filter capacitor Cgnd, a first filter resistor RP1 and a second filter resistor RP 2;
one end of the first filter resistor RP1 is an input end of the first low-pass filter and the second low-pass filter, the other end of the first filter resistor RP1 is connected with one end of the second filter resistor RP2, and the other end of the second filter resistor RP2 is connected with a non-inverting input end of the operational amplifier Ul;
the non-inverting input end of the operational amplifier Ul is grounded through the filter capacitor Cgnd;
the output end of the operational amplifier Ul is directly connected with the inverting input end of the operational amplifier Ul;
the output end and the inverting input end of the operational amplifier Ul are both connected with the other end of the first filter resistor RP1 through the feedback capacitor;
the output end of the operational amplifier Ul is the output ends of the first low-pass filter and the second low-pass filter;
the feedback resistor Rf is a resistor with the resistance value of 2.558k omega; the filter resistor Rgnd is a resistor with the resistance value of 5.114k omega; the first filter capacitor CP1 and the second filter capacitor CP2 both adopt capacitors with capacitance values of 22 nF; the feedback capacitor is a capacitor with a capacitance value of 56.26 nF; the filter capacitor Cgnd selects a capacitor with a capacitance value of 28.13 nF; the first filter resistor RP1 and the second filter resistor RP2 both adopt resistors with the resistance value of 2k omega, wherein the positive power supply ends of the operational amplifier Uh and the operational amplifier Ul are connected with a positive 15V power supply, and the negative power supply end is connected with a negative 15V power supply.
2. The frequency divider circuit of claim 1, further comprising a third high pass filter;
the output end of the third high-pass filter is respectively connected with the input end of the first filter unit and the input end of the second filter unit;
and the input end of the third high-pass filter is used for inputting the sound source signals and filtering the secondary low-frequency signals in the sound source signals.
3. The frequency divider circuit of claim 2, further comprising a frequency response equalization circuit;
the output end of the frequency response equalizing circuit is connected with the input end of the third high-pass filter;
the input end of the frequency response equalization circuit is used for inputting the sound source signal.
4. A frequency divider, comprising a frequency divider housing, and the frequency divider circuit of any of claims 1 to 3 disposed within the frequency divider housing.
5. A two-tone audio system comprising a tweeter unit, an audio power amplifier corresponding to the tweeter unit, a woofer unit, an audio power amplifier corresponding to the woofer unit, and the crossover circuit of any one of claims 1 to 3;
the output end of the first filter unit is used for being connected with an audio power amplifier of a high pitch loudspeaker unit corresponding to the high pitch loudspeaker unit, the output signal of the first filter unit is transmitted to the audio power amplifier of the corresponding high pitch loudspeaker unit, and the high pitch loudspeaker unit produces sound after power amplification;
the output end of the second filter unit is used for being connected with the audio power amplifier of the bass loudspeaker unit corresponding to the bass loudspeaker unit, transmitting the output signal of the second filter unit to the audio power amplifier of the corresponding bass loudspeaker unit, and after power amplification, the bass loudspeaker unit produces sound.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810457404.1A CN108540905B (en) | 2018-05-14 | 2018-05-14 | Frequency divider circuit and frequency divider |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810457404.1A CN108540905B (en) | 2018-05-14 | 2018-05-14 | Frequency divider circuit and frequency divider |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108540905A CN108540905A (en) | 2018-09-14 |
| CN108540905B true CN108540905B (en) | 2021-09-10 |
Family
ID=63477385
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810457404.1A Active CN108540905B (en) | 2018-05-14 | 2018-05-14 | Frequency divider circuit and frequency divider |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108540905B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR102475665B1 (en) * | 2020-11-12 | 2022-12-07 | 엑스멤스 랩스 인코포레이티드 | Crossover Circuit |
| CN113055782A (en) * | 2021-02-02 | 2021-06-29 | 头领科技（昆山）有限公司 | Frequency-division optimization processing audio chip and earphone |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4755774A (en) * | 1985-07-15 | 1988-07-05 | Motorola Inc. | Two-port synthesizer modulation system employing an improved reference phase modulator |
| CN2109664U (en) * | 1991-11-12 | 1992-07-08 | 耿纯 | Full bandpass filter electron frequency divider |
| CN2342537Y (en) * | 1998-08-26 | 1999-10-06 | 李锡放 | Digit control household sound equipment |
| CN200976587Y (en) * | 2006-10-31 | 2007-11-14 | 英华达(上海)电子有限公司 | Device for realizing audio frequency dividing output and adjustment on handhold equipment |
| CN102761802A (en) * | 2012-08-04 | 2012-10-31 | 鲍善翔 | Three-frequency divider |
| CN106303779A (en) * | 2015-06-03 | 2017-01-04 | 阿里巴巴集团控股有限公司 | Earphone |
-
2018
- 2018-05-14 CN CN201810457404.1A patent/CN108540905B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4755774A (en) * | 1985-07-15 | 1988-07-05 | Motorola Inc. | Two-port synthesizer modulation system employing an improved reference phase modulator |
| CN2109664U (en) * | 1991-11-12 | 1992-07-08 | 耿纯 | Full bandpass filter electron frequency divider |
| CN2342537Y (en) * | 1998-08-26 | 1999-10-06 | 李锡放 | Digit control household sound equipment |
| CN200976587Y (en) * | 2006-10-31 | 2007-11-14 | 英华达(上海)电子有限公司 | Device for realizing audio frequency dividing output and adjustment on handhold equipment |
| CN102761802A (en) * | 2012-08-04 | 2012-10-31 | 鲍善翔 | Three-frequency divider |
| CN106303779A (en) * | 2015-06-03 | 2017-01-04 | 阿里巴巴集团控股有限公司 | Earphone |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108540905A (en) | 2018-09-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4243021B2 (en) | Crossover network without capacitors for electroacoustic speakers | |
| EP1847101B1 (en) | Audio device for improved sound reproduction | |
| US10701487B1 (en) | Crossover for multi-driver loudspeakers | |
| CN101534467A (en) | Condenser microphone | |
| EP2705672B1 (en) | Method for determining an impedance of an electroacoustic transducer and for operating an audio playback device | |
| CN108540905B (en) | Frequency divider circuit and frequency divider | |
| JP2007028419A (en) | Speaker driving apparatus | |
| CN1914950B (en) | First-order loudspeaker crossover network | |
| JP2014154956A (en) | Channel divider, voice reproduction system including the same, and method for setting cross-over frequency | |
| US6775385B1 (en) | Loudspeaker frequency distribution and adjusting circuit | |
| CN108600916B (en) | Acoustic circuit and system | |
| JP3147662B2 (en) | Sound reproduction device | |
| JPS59146296A (en) | Driving method of piezoelectric speaker | |
| CN207266237U (en) | A kind of audio player module and earphone | |
| JP6015161B2 (en) | Channel divider and audio playback system including the same | |
| US20240147396A1 (en) | Method and apparatus for mitigating phase interference or cancellation by aligning waveforms to 3rd harmonics | |
| CN220422019U (en) | Passive mirror image filtering low-frequency extension circuit | |
| CN104023296A (en) | Sound output method and device and mobile terminal | |
| CN216960171U (en) | Audio regulating circuit, audio amplifying circuit and audio playing device | |
| JP2014175883A (en) | Channel divider and sound reproduction system including the same | |
| US5129005A (en) | Electrodynamic loudspeaker | |
| JP2018046396A (en) | Sound reproduction system and termination processing circuit constituting the same | |
| JP4085453B2 (en) | Low-frequency electroacoustic transducer with amplification circuit | |
| JPH04320199A (en) | Acoustic reproducing device | |
| WO2016100237A1 (en) | Ultra-low distortion integrated loudspeaker system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |