Condenser microphones use changes in the size of capacitors to convert sound signals into electrical signals. This kind of microphone is the most common, such as the built-in microphone of a common recorder. Because it is cheap, compact, and the effect is not bad. Sometimes called Mitou.
Condenser microphones have 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, the gate and the source A diode is connected between the poles. When the electret diaphragm itself is charged, the surface charge is Q, and the capacitance between the plates is C, then a ground voltage U=Q/C is generated on the pole tip. When vibrating or being rubbed by airflow, the distance between the two plates is changed due to the vibration, that is, the capacitance C changes, but the electric quantity Q does not change, which will cause the voltage change. The magnitude of the voltage change reflects the strength of the external sound pressure. The frequency of this voltage change reflects the frequency of external sounds, which is the working principle of electret microphones.
What is the principle of a condenser microphone
With the development of the entertainment industry now, let us see the existence of condenser microphones in different recording studios. Many people are highly concerned about the principle of condenser microphones. In the end, why can such a small item exert such an amazing effect? Many people in the industry also refer to condenser microphones as electret microphones.
To understand the principle of condenser microphones, first let's take a look at the composition of condenser microphones. The main structure of the microphone is the stage head, which is composed of two high-quality metal films. When we are singing or talking, the sound wave will cause the vibration of the stage head. At this time, the metal film spacing is different, which constitutes the gap of the capacitance, which generates different degrees of current.
In addition, the principle of condenser microphones requires the power of phantom power to maintain normal operation and work. Simply put, no matter where the condenser microphone is used, such as a computer or recording equipment. All need to cooperate with the power supply of the phantom power supply, so that there will be no gap in the recording effect and maintain an optimal state.
Condenser microphones have become very common nowadays. The principle of the new generation of condenser microphones has not only been perfected, but also made sound effects better. It has also been debugged in terms of volume and price. Nowadays, condenser microphones are not only small and light, but also have a good grasp of directivity and sensitivity. We can not only see the equipment in various recording studios, but also in many professional concerts and related venues.
Nowadays, there are many small workshops selling condenser microphones on the market, but the principle and quality of condenser microphones are not up to standard at all. It is recommended that you choose professional and regular brand products. In addition, you should pay more attention to the correct connection and installation methods of condenser microphones. Condenser microphones have existed a long time ago. Its overall mechanical structure is relatively simple, but its role cannot be ignored.
Through the above introduction, I wonder if you have a basic understanding of the principle of condenser microphones. Nowadays, the use of condenser microphones requires not only a combination of phantom power supply, but also different microphone amplifier materials and related tuning equipment to make the product play the best effect. If you want to know more about condenser microphone knowledge and information, you are welcome to pay attention to the IT Encyclopedia website at any time.
Condenser microphones are also called electret microphones. The core component of condenser microphones is the stage head, which is composed of two metal films; when sound waves cause it to vibrate, the difference in the distance between the metal films causes a difference in capacitance and generates current. Condenser microphones generally require 48V phantom power supply, microphone amplifier materials, or mixers to work. Condenser microphone has the characteristics of high sensitivity and high directivity. Therefore, it is generally used in various professional music, film and television recordings, and is very common in recording studios.
Features of condenser microphones
1. With ultra-high sensitivity
Because there is no voice coil restriction on the vibrating membrane, the condenser microphone uses an ultra-thin metal plastic membrane, which not only has superior frequency response, but also has good sensitivity. It can sense weak sound waves and transmit clear and delicate sounds.
2. It has the characteristics of anti-fall and impact resistance
I believe that when you sing in KTV, the microphone in your hand will inevitably fall or hit the table and cause it to malfunction. However, because the condenser capsule is made of lighter weight plastic parts and a strong metal shell, even When the microphone falls on the ground, the impact force is less, and the probability of damage is low.
3. Small size and light weight
Condenser microphones use ultra-thin diaphragms, which have the characteristics of light weight, small size, and high sensitivity.
The pursuit of a good condenser microphone is the reproduction of the original sound,
Advantages and disadvantages of condenser microphones
Can convert sound directly into electrical energy signal
Condenser microphones use the principle of capacitor charging and discharging between conductors. Ultra-thin metal or gold-plated plastic film is used as a vibrating film to induce sound pressure, which changes the static voltage between conductors and directly converts them into electrical energy signals, which are practically coupled by electronic circuits The output impedance and sensitivity are designed.
Can show the characteristics of original sound reproduction
The audio experts take the pursuit of "reproduction of the original sound" as the highest level of audio! From the analysis of the basic design principles of microphones, it is not difficult to find that condenser microphones not only rely on sophisticated mechanical manufacturing technology, but also combine complex electronic circuits to directly convert sound into electrical energy signals. They have inherently superior characteristics, so they become a pursuit. The best choice for those who "reproduce the original sound".
Has an extremely wide frequency response
The diaphragm is the main component of the microphone that senses sound and converts it into electrical energy signals. The material of the diaphragm and the design of the mechanism determine the characteristics of the microphone's sound quality. Because the diaphragm of a condenser microphone can be made of extremely thin materials, and the induced sound pressure is directly converted into an audio signal, the frequency response of the bass can be extended to ultra-low frequencies below 10 Hz, and the high frequency can easily reach tens of KHz. Ultrasound, showing very wide frequency response characteristics!
With ultra-high sensitivity
Because there is no voice coil load on the diaphragm, an extremely thin and light design can be adopted, so not only the frequency response is extremely superior, but also has excellent sensitivity, can sense extremely weak sound waves, and output the clearest, finest and accurate original sound!
Fast transient response characteristics
In addition to the characteristics of the diaphragm that determine the frequency response and sensitivity of the microphone, the ability to respond to sound waves, the so-called "transient response" characteristics, is one of the most important factors affecting the timbre of the microphone. The speed of the microphone's transient response characteristics is determined by the weight of the entire diaphragm. The lighter the diaphragm, the faster the response speed. The extremely thin diaphragm of the condenser capsule has extremely fast transient response characteristics, which can show clear, bright and powerful sound and precise audio and video. In particular, there is no sound staining and "box sound" in the middle and low frequencies, and the high pitch is delicate and crisp, which is the most significant timbre characteristic of the capacitive type. It can be clearly seen from the following figure that the transient response characteristics of the condenser capsule are much better than those of the moving coil.
Features ultra-low touch noise
When using a handheld microphone, the touch noise caused by contact with the palm of the hand makes the original sound mixed with additional noise, which has a huge impact on the sound quality, especially for wireless microphones with preamplifier circuits, so the touch noise becomes a judge of the quality of the microphone. Important project. From the perspective of physical phenomena, the goose feathers fall to the floor like the copper plate, and the goose feathers can hardly hear the falling sound, while the copper plate is very loud, indicating that the lighter material has less impact than the heavier. In the same way, the diaphragm of a condenser microphone is relatively light, and inherently has the excellent characteristics of "ultra-low touch noise".
Has the characteristics of drop resistance and impact resistance
Using the microphone will inevitably cause malfunctions or abnormalities due to accidental drop and collision. Since the condenser capsule is composed of lighter plastic parts and a strong light metal shell, the impact force of falling to the ground is small, and the failure rate of damage is low
Small size and light weight
Condenser microphone adopts ultra-thin diaphragm, which has the characteristics of small size, light weight, high sensitivity and superior frequency response, so it can be designed as an ultra-small microphone (commonly known as little bee and little ant) for a wide range of applications
Most suitable for mounting on wireless microphones
Condenser microphones have the above-mentioned excellent characteristics and have become the favorite of sound engineering experts and singers. Wireless microphones have become a trend in the world today to sing on stage or karaoke at home. Wireless microphones can provide capacitive sound by themselves. It has all the advantages of condenser microphones, and has become the best microphone that professional audio experts dream of in the digital audio era.
The structure is complicated, the cost is expensive, the sound film is fragile, and the sound film is afraid of the tide.
How to use condenser microphones
The use of condenser microphones can be roughly divided into the following three types:
1. Handheld condenser microphone:
Hand-held condenser microphones first need to install a DC battery to power the microphone. After installation, push the microphone reed switch to the upper microphone to work.
The connection method of the microphone and the sound card is to first connect the XLR end of the microphone cable to the tail of the microphone, and connect the other end of the microphone cable to the microphone input jack of the computer, sound card, mixer, power amplifier and other equipment. To connect mixers, power amplifiers and other equipment, you need a 3.5 to 6.35 adapter.
2. Large, medium and small diaphragm and electronic tube, vacuum tube condenser microphone:
This type of microphone is called a professional recording condenser microphone in the industry. The method of use is to first install the microphone on the shock mount at the front of the stand, then plug one end of the male and female XLR cable into the bottom jack of the microphone, and connect the other end to the phantom power supply or microphone amplifier, mixer, phantom On the XLR interface of the power supply, connect the XLR to 3.5 microphone cable to the phantom power supply and the sound card. After finishing, turn on the power switch of the mixer or mic preamp and phantom power to use.
3. Condenser microphone without power supply:
This kind of microphone is a new type of condenser microphone that has appeared in the last one or two years. Its feature is that it can work without phantom power and battery power, and it is very simple to install and use. The method is to connect the XLR end of the microphone cable to the end of the microphone, and plug the other 3.5 plug directly into the microphone input jack of the computer, sound card, phantom power supply or mixer.