What is the principle of the capacitor microphone capsule and how to make it 2

Unfortunately, I have just been verifying the principle of the capacitor microphone recently, and I also tried to make one myself, and the production was successful, and the sensitivity was not so high, probably because the diaphragm was too thick, and the amplitude of the same sound thick film was smaller, resulting in a small change in capacitance, so the signal amplitude was smaller, so the sensitivity was low.

How to make it: Use PCB to make a porous back plate, the middle of the back plate is a piece of metal copper round, surrounded by screw holes The screw holes are insulated from the middle metal plate (this is to facilitate the installation of simple diaphragms under amateur conditions, and the diaphragm materials are replaced by other materials, which are all frontally conductive, so the substrate on the PCB is made to be insulated with the surrounding screw holes and directly covered with a whole conductive film will not be short-circuited).

Make a diaphragm pressure ring (I took a name casually), the effect is that the holes around the ring are facing the screw holes around the back plate, and then the diaphragm is pressed on the back plate and then put this pressure ring on it, and then tighten it with screws around it, so that the diaphragm and the back plate are pressed together The diaphragm can also be pressed, and the screw holes around the pressure ring are all made into non-soldering mask, so that the diaphragm can be pressed at the same time as you can also contact the conductive layer of the diaphragm, and the back diaphragm lead line can be drawn out of the screw as long as it is drawn out of the screw.

In addition, the screw hole on the back plate can be smaller than the diameter of the screw, so that the screw is directly screwed on the back plate without additional nuts to fix, and the screw hole of the pressure ring can just let the screw pass through.

The above renderings and PCB design drawings are below.

Design drawing of the back plate.

Pressing ring design drawing.

Conductive non-solder mask rendering around the pressing ring.

Physical diaphragm surface.

Physical back plate surface.

5.The wiring is connected from the screws around the perimeter, and the other is soldered from the pad in the center of the back plate.

6.Material description: The torture material is a field life-saving blanket, a treasure yuan free shipping is one meter by one meter, choose the voucher area when using, avoid creases, creases are generally coated with fractures, non-conductive.

This sentence or two is not clear, provide information for your reference.

Microphone production library.

Let's take a look here

A very thin film sputters a very thin layer of rare metals.

Condenser microphone principle: A condenser microphone has two metal plates, one of which is coated with an electret film (mostly polyperfluoroethylene propylene) and grounded, and the other plate is connected to the gate of the field-effect transistor, and a diode is connected between the gate and the source. When the electret diaphragm itself has an electric charge, the surface charge is Q, and the ground capacitance between the plates and poles is C, then the ground voltage U=Q C is generated on the pole head, when it is subjected to vibration or rubbed by the air flow, the distance between the two plates is changed due to vibration, that is, the capacitance C changes, and the amount of electricity Q does not change, it will cause a change in voltage, the magnitude of the voltage change, reflects the strength of the external sound pressure, and the frequency of this voltage change reflects the frequency of the external sound, which is the working principle of the electret microphone.

A capacitor microphone is actually a capacitor in which one pole of the capacitor moves in response to sound waves. The motion changes the capacitance of the capacitor, and these changes are amplified to produce a measurable signal. Condenser microphones typically use a small battery that provides voltage to the capacitor.

It is designed by using the principle of capacitive charging and discharging between conductors, using ultra-thin metal or gold-plated plastic film as the vibrating film to induce sound pressure, and directly converting the electrostatic voltage between conductors into electrical energy signals, and obtaining practical output impedance and sensitivity through electronic circuit coupling.

First, the principle is different.

1. Microphone: The use of a polymeric material diaphragm with permanent charge isolation converts the sound signal into an electrical signal.

2. Condenser microphone: use the change of capacitor size to convert the sound signal into an electrical signal.

Second, the structure is different.

1. Microphone: The diaphragm vibrates through the air with the human voice, and then the electromagnetic coil winding on the diaphragm and the magnet surrounding the moving coil microphone form a magnetic field to cut and form a weak fluctuating current.

2. Condenser microphone: There are two metal plates, one of which is coated with an electret film (mostly polyperfluoroetylene) and grounded, and the other plate is connected to the gate of the field-effect transistor.

Third, the advantages are different.

1. Microphone: The output voltage generated on the microphone is equal to the output voltage generated by the inherent noise of the microphone itself, and the sound pressure of the sound wave is equal to the equivalent noise level of the microphone.

2. Condenser microphone: It not only relies on precise mechanism manufacturing technology, but also combines complex electronic circuits to directly convert sound into electrical energy signals, which has extremely superior characteristics.

A normal microphone is a dynamic microphone.

This dynamic microphone uses the principle of electromagnetic induction, which is mounted on the diaphragm by a wire coil, and then placed between the magnetic fields of the magnet, and continuously moves in the magnetic field with the change of sound pressure to generate induced current, thereby transforming the sound signal into an electrical signal.

Condenser microphone.

Using the principle of charging and discharging capacitors, the vibration of sound drives one of the plates (ultra-thin metal film) of the capacitor, and the vibration of this plate changes the distance between the two plates, which in turn changes the capacitance. When the capacitance becomes larger, the power supply charges the capacitor; When the capacitance becomes smaller, the capacitor discharges, which generates an electric current in the circuit and converts the sound signal into a telegraphic signal.

The sensitivity of the dynamic microphone picks up only the sound in the front range. It is more suitable for on-site KTV noisy environments.

Condenser microphones are highly sensitive. The pickup goes in a big range. Minor details can be recorded.

But you need phantom power to put these to drive it up.

Let's put it this way, the capacitor microphone can even record you chewing cucumbers clearly, so the use conditions are very harsh and require a particularly quiet environment; The radio of the ordinary microphone (dynamic microphone) only collects the sound of a small area in the front, so the use conditions are not so picky, and it can also be used in noisy environments. It's impossible to say who's good and who's bad, and the characteristics are different and the uses are different.

I don't know!! The condenser microphone has high sensitivity, good dynamics, and delicate timbre, which is suitable for recording single vocals or musical instruments in a quiet environment. Ordinary microphones are more solid and suitable for noisy recording environments, but the sensitivity and dynamics will be poor.

If the environment is noisy, then the recording effect with a condenser microphone is very poor, it has relatively high requirements for the environment, and the sound absorption effect of the condenser microphone is particularly strong! Generally, microphones do not need to be powered, but condenser microphones do, usually with a 48V power supply microphone amplifier to power them.

The condenser microphone has a wide range of sound and high clarity. High sensitivity!

The high-frequency characteristics of the capacitor microphone are good! High impedance! High randomness! High sensitivity! But the frequency response is not wide enough!

The low-frequency characteristics of the dynamic type are good! Wide frequency response! But the impedance is low! Low sensitivity! Impedance matching and microphone amplification required!

If you are recording in general, the capacitor microphone is enough! If you record professionally! The dynamic type is the best grade!

Both condenser microphones and moving coil microphones are components that turn audio signals into electrical signals. The capacitor microphone uses the pressure change of the sound wave to transform into the change of capacitance, thereby causing the change of current. The capacitor microphone has good high-frequency characteristics, high input impedance and high sensitivity, but the frequency response is not wide enough.

The dynamic coil of the moving coil microphone is an inductive coil, and the generation of the sound signal of this microphone is mainly completed by the continuous movement of the wire coil closely connected to the diaphragm in the magnetic field according to the change of sound pressure. Due to the relatively large size of the moving part, dynamic microphones are slightly inferior to condenser microphones in terms of response frequency range (mainly high-frequency parts), sensitivity, and instantaneous response. A dynamic microphone has a voice coil that is fixed to a diaphragm and a permanent magnet that is highly magnetic near the voice coil, which is equivalent to the structure of a loudspeaker and a diaphragm that is equivalent to a paper cone.

When the microphone is working, the sound wave acts on the diaphragm, so that the diaphragm produces mechanical vibration, which drives the voice coil to vibrate in the magnetic field, and the voice coil outputs an audio electrical signal by the excitation electricity, which is the sound converted into an electrical signal. The pressure dynamic type of sound wave has good low-frequency characteristics and wide frequency response, but the impedance is low and the sensitivity is low, so impedance matching and microphone amplification are required. If you are recording in general, the capacitor microphone is enough!

If you record professionally! The dynamic type is the best grade!

Do you want to bai shout mai brother? The difference between capacitor du wheat and dynamic microphone: 1. Capacitor wheat zhi:dao as the name suggests.

It is an internal microphone that requires power supply. It can be divided into two categories, one is handheld microphones, such as microphones in stage performances and KTV. This battery-powered handheld condenser microphone is generally a No. 5 battery; The other is a recording microphone, such as the one used in radio studios and studios, which requires 48 volts of phantom power.

The characteristics of the condenser microphone are: high clarity and sensitivity, full and rich sound quality but not turbid, the disadvantage is that the sensitivity is too high, not suitable for high-noise places. 2. Moving coil microphone:

Because the generation of the sound signal of this microphone is mainly completed by the continuous movement of the wire coil closely connected to the diaphragm in the magnetic field according to the change of sound pressure, without DC working voltage, that is, no power supply. It is easy to use and has low noise. The sound quality of the dynamic microphone is characterized by richness, fullness and strong noise immunity.

The disadvantages are that the volume is small, the voice is muffled, and the clarity and sensitivity are not good enough. As a result, capacitive microphones are suitable for use at home and in the studio. Hope it helps. Adopt it.

The sound of a large diaphragm is a little louder than that of a small diaphragm. The sensitivity to sound is relatively high.

The sampling range of sound is also larger than that of a small diaphragm.

Generally speaking, large diaphragms are suitable for use in a cleaner environment, such as a recording studio. Recording studios in these environments.

Small diaphragms are generally more suitable for personal and family use.

Scene. KTVs: These are those ordinary microphones. The dynamic circle is sensitive to the microphone of the majority of the Kaina Wang staring boy. Suitable for use in noisy environments.

Professional recording. It's a condenser microphone. This requires a quiet environment.