A circuit for adjusting the polarized voltage of a double diaphragm sound head to change the directivity

Abstract

The utility model discloses a kind of adjusting double-vibration-membrane sound head polarization voltage change directivity circuit, it is related to audio equipment technical field, to solve the problem of existing sound head directivity adjustment circuit complex structure, switching stability is poor. The circuit includes sound head Q1, multiple resistors, capacitor and two switches, by the interface combination of switching switch K3 and K4, change the distribution path and impedance matching relationship of sound head polarization voltage, realize the stable switching of O type, 8 character type, heart type, super heart type four directivities;While through the reasonable collocation of capacitor and resistor, optimize signal filtering effect and circuit stability. The utility model structure is simple, and adjustment is convenient, applicable to various audio acquisition equipment needing flexible adjustment directivity.

Description

Technical Field

[0001] This utility model relates to the field of microphone technology, and in particular to a circuit for adjusting the polarization voltage of a dual-diaphragm microphone to change its directivity. Background Technology

[0002] As the core component of audio acquisition equipment, the directivity of the microphone capsule determines its sensitivity to sound from different directions. Common directivity patterns include O-shape, figure-eight, cardioid, and supercardioid. In existing technologies, the directivity adjustment of dual-diaphragm microphone capsules is mostly achieved through complex circuit structures, which suffers from poor switching stability, inadequate filtering, and unreasonable impedance matching, thus affecting audio acquisition quality. Therefore, we propose a circuit that adjusts the polarization voltage of a dual-diaphragm microphone capsule to change its directivity. Utility Model Content

[0003] To address the aforementioned problems, this invention provides a circuit for adjusting the polarization voltage of a dual-diaphragm microphone head to change its directivity. This invention solves the problem that in existing technologies, microphone head directivity adjustment is often achieved through complex circuit structures, resulting in poor switching stability, inadequate filtering, and unreasonable impedance matching, all of which negatively impact audio acquisition quality.

[0004] This utility model discloses a circuit for adjusting the polarization voltage of a dual-diaphragm microphone to change its directivity. It includes resistors R1, R24, R25, R26, R27, R28, R29, R30, and R31; capacitors C1, C24, C25, and C26; switches K3 and K4; and a microphone head Q1. The I-pin of microphone head Q1 is connected to resistor R1; the 0° pin of Q1 is connected to resistor R31; the 180° pin of microphone head Q1 is connected to resistor R29; capacitor C25 is connected in parallel between the I-pin and 180° pins of microphone head Q1; capacitor C1 is connected to the I-pin of microphone head Q1; the end of resistor R31 furthest from microphone head Q1 is connected to capacitor C26; and resistor R29 is connected to the I-pin of switch K3. The circuit is as follows: Switch K3's pin 2 is grounded; Switch K3's pin 3 is connected to capacitor C24; Resistor R29 is connected to resistor R28; Resistor R28 is connected to switch K4's pin 1; Switch K4's pin 2 is connected to resistor R26; Resistor R26 is connected to resistor R27; Switch K4's pin 3 is connected to resistor R24; Resistor R24 ​​is connected to capacitor C24; Resistor R25 is connected in parallel between Switch K4's pins 2 and 3; The end of resistor R24 ​​furthest from resistor R25 is connected to the input voltage VCC; Resistor R31's end closest to resistor R30 is connected to resistor R1; The end of resistor R1 furthest from the tone head Q1 is connected to capacitor C26.

[0005] In the above scheme, the end of capacitor C24 furthest from resistor R30 is grounded.

[0006] In the above scheme, the end of capacitor C26 furthest from resistor R1 is grounded.

[0007] In the above scheme, the end of resistor R27 furthest from resistor R26 is grounded.

[0008] In the above scheme, the 0° interface terminal of the microphone Q1 is grounded.

[0009] In the above scheme, the 180° interface terminal of the microphone Q1 is grounded.

[0010] In the above scheme, the 2nd interface of switch K3 is marked with an O-type mark, the 3rd interface of switch K3 is marked with an 8-type mark, the 2nd interface of switch K4 is marked with a heart-shaped mark, and the 3rd interface of switch K4 is marked with a superheart-shaped mark.

[0011] In the above scheme, the input voltage of the input voltage VCC is 90V.

[0012] The advantages and beneficial effects of this utility model are as follows: This utility model provides a circuit for adjusting the polarization voltage of a dual-diaphragm microphone to change the directivity. The structure is simple, and four types of directivity can be adjusted by switching between two switches. It is easy to operate. The reasonable combination of capacitors and resistors optimizes the filtering effect and impedance matching, improves the circuit stability and audio acquisition quality, and the input power supply adopts a 90V polarization voltage, which is compatible with the working requirements of mainstream microphones and has a wide range of applications. Attached Figure Description

[0013] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0014] Figure 1 This is a schematic diagram of the circuit structure of this utility model. Detailed Implementation

[0015] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings and examples. The following examples are only used to more clearly illustrate the technical solution of this utility model and should not be construed as limiting the scope of protection of this utility model.

[0016] like Figure 1As shown, this utility model is a circuit for adjusting the polarization voltage of a dual-diaphragm microphone to change its directivity. It includes resistors R1, R24, R25, R26, R27, R28, R29, R30, and R31; capacitors C1, C24, C25, and C26; switches K3 and K4; and a microphone head Q1. The I-pin of microphone head Q1 is connected to resistor R1; the 0° pin of Q1 is connected to resistor R31; the 180° pin of microphone head Q1 is connected to resistor R29; capacitor C25 is connected in parallel between the I-pin and 180° pins of microphone head Q1; capacitor C1 is connected to the I-pin of microphone head Q1; the end of resistor R31 furthest from microphone head Q1 is connected to capacitor C26; and resistor R29 is connected to the I-pin of switch K3. The following circuits are connected: Switch K3's pin 2 is grounded; Switch K3's pin 3 is connected to capacitor C24; Resistor R29 is connected to resistor R28; Resistor R28 is connected to switch K4's pin 1; Switch K4's pin 2 is connected to resistor R26; Resistor R26 is connected to resistor R27; Switch K4's pin 3 is connected to resistor R24; Resistor R24 ​​is connected to capacitor C24; Resistor R25 is connected in parallel between Switch K4's pins 2 and 3; The end of resistor R24 ​​furthest from resistor R25 is connected to the input voltage VCC; Resistor R31's end closest to resistor R30 is connected to resistor R1; The end of resistor R1 furthest from the tone head Q1 is connected to capacitor C26.

[0017] The end of capacitor C24 furthest from resistor R30 is grounded.

[0018] The end of capacitor C26 furthest from resistor R1 is grounded.

[0019] The end of resistor R27 furthest from resistor R26 is grounded.

[0020] The 0° interface terminal of the microphone Q1 is grounded.

[0021] The 180° interface terminal of the microphone Q1 is grounded.

[0022] The 2nd interface of switch K3 is marked with an O-shaped mark, the 3rd interface of switch K3 is marked with an 8-shaped mark, the 2nd interface of switch K4 is marked with a heart-shaped mark, and the 3rd interface of switch K4 is marked with a superheart-shaped mark.

[0023] The input voltage VCC is 90V.

[0024] Specifically, in this utility model, when the switch position is cardioid: the input voltage VCC is powered to the 0 terminal of the microphone head Q1 through resistors R30 and R31 to enable its operation; the other input voltage VCC is divided in series through resistors R24, R25 and R26, and then powered to the 180° terminal of the microphone head Q1 through resistors R28 and R29. The polarization voltage of the microphone's front diaphragm is higher than that of the rear diaphragm. When the sound wave is incident from the front, the capacitance of the front diaphragm changes significantly, while the sound wave from the rear is suppressed due to phase cancellation. When the switch is in supercardioid mode: the input voltage VCC powers the 0° connector of the microphone head Q1 via resistors R30 and R31, enabling its operation. The other 90V VCC is divided in series via resistors R24 and R25, and then powers the 180° connector of the microphone head Q1 via resistors R28 and R29. By adjusting the polarization voltage difference between the two diaphragms, the voltage of the front diaphragm is higher than that of the rear diaphragm, causing a change in in-phase capacitance in the sound pressure directly in front. Lateral sound pressure is suppressed due to the phase difference, resulting in a narrow pickup range of approximately 110-115°. When the switch is in the figure-eight position: the input voltage VCC powers the 0° connector of the microphone head Q1 via resistors R30 and R31, while the other 90V VCC powers the 180° connector of the microphone head Q1 via resistor R29. The two diaphragms are subjected to polarized voltages of opposite polarities, creating electric fields in opposite directions, resulting in a 180° phase difference between the preceding and following sound wave signals. When the switch is in the O-type omnidirectional position: the polarization voltages of the two diaphragms are the same, and the output signals of the two diaphragms are superimposed in phase through the circuit, eliminating directional deviation and achieving 360° uniform sound pickup.

[0025] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A circuit for adjusting the polarization voltage of a dual-diaphragm microphone to change its directivity, comprising resistors R1, R24, R25, R26, R27, R28, R29, R30, and R31; capacitors C1, C24, C25, and C26; switches K3 and K4; and a microphone head Q1, characterized in that... The input terminal Q1 is connected to resistor R1 at pin 1, resistor R31 at pin 0°, and resistor R29 at pin 180°. A capacitor C25 is connected in parallel between pins Q1 and 180°. Capacitor C1 is also connected to pin 1 of pin Q1. The end of resistor R31 furthest from pin Q1 is connected to capacitor C26. Resistor R29 is connected to pin 1 of switch K3. Switch K3 is grounded at pin 2. Switch K3 is connected to capacitor C24 at pin 3. Resistors R29 and R28 are connected in parallel. The resistor R28 is connected to port 1 of switch K4. Port 2 of switch K4 is connected to resistor R26. Resistor R26 is connected to resistor R27. Port 3 of switch K4 is connected to resistor R24. Resistor R24 ​​is connected to capacitor C24. Resistor R25 is connected in parallel between ports 2 and 3 of switch K4. The end of resistor R24 ​​furthest from resistor R25 is connected to the input voltage VCC. The end of resistor R31 closest to resistor R30 is connected to resistor R1. The end of resistor R1 furthest from the tone head Q1 is connected to capacitor C26.

2. The circuit for adjusting the polarization voltage of a dual-diaphragm microphone to change directivity according to claim 1, characterized in that, The end of capacitor C24 furthest from resistor R30 is grounded.

3. The circuit for adjusting the polarization voltage of a dual-diaphragm microphone to change directivity according to claim 1, characterized in that, The capacitor C26 is grounded at the end furthest from resistor R1.

4. The circuit for adjusting the polarization voltage of a dual-diaphragm microphone to change directivity according to claim 1, characterized in that, The end of resistor R27 furthest from resistor R26 is grounded.

5. The circuit for adjusting the polarization voltage of a dual-diaphragm microphone to change directivity according to claim 1, characterized in that, The 0° interface terminal of the microphone Q1 is grounded.

6. The circuit for adjusting the polarization voltage of a dual-diaphragm microphone to change directivity according to claim 1, characterized in that, The 180° interface terminal of the microphone Q1 is grounded.

7. The circuit for adjusting the polarization voltage of a dual-diaphragm microphone to change directivity according to claim 1, characterized in that, The 2nd interface of switch K3 is marked with an O-shaped mark, the 3rd interface of switch K3 is marked with an 8-shaped mark, the 2nd interface of switch K4 is marked with a heart-shaped mark, and the 3rd interface of switch K4 is marked with a superheart-shaped mark.

8. The circuit for adjusting the polarization voltage of a dual-diaphragm microphone to change directivity according to claim 1, characterized in that, The input voltage VCC is 90V.

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