Condenser microphone - what is it

Condenser microphone - a unique device for recording sound. Mainly used for studio recording. Currently, this device is widely used and is widely used in the music industry.

The peculiarity of a condenser microphone

This device has gained popularity due to its unique qualities, which provide high quality sound recordings.

Large dynamic range allows you to record sounds of different frequencieswithout losing quality both in high spectral regions and in low ones.

Due to this property, musical instruments recorded with such a microphone sound most deeply, while maintaining all the depth. Besides, the device has a uniform frequency response, which provides amplitude balance throughout the spectrum, without loss in any area.

Operating principle

The recording process is based on the properties of an electric capacitor. It consists of two plates, one of which is made of elastic film.

During the action of directional sound waves (voice or music), the soft lining vibrates, thereby changing the capacitance of the capacitor. Changing the capacitance of the capacitor allows you to modulate a constant signal according to a change in external waves.

The received AM signal will contain information about the recorded sound in the envelope.

IMPORTANT! To record, the capacitor must be charged, in other words, voltage must be applied to the microphone.

Commonly used phantom power technology. It lies in the fact that the useful signal is transmitted along the same channels and stages as the supply voltage.

Types of microphones

In addition to a condenser microphone, there are also devices with a similar principle of operation. They are called electret microphones. They are of two types.

Homoelectric microphones.

The difference between these devices is that the membrane film is placed in the gap of the capacitor or on the lining. As a result, when exposed to sound waves, the membrane shifts, and the voltage from the capacitor changes in accordance with the frequency of the acoustic signal.

Usually, a preamplifier made on a transistor is included in the design, since the output signal is too weak and there is a high probability of noise.

Heteroelectric Microphones

They differ from homoelectret in that the membrane is a heteroelectret wall. Under the influence of directed sound waves, charges of different polarity appear on its surface. Their registration is carried out by electrodes located on the surface of this film.

Advantages and disadvantages of condenser microphones

Pros

• Dynamic range. The main advantage of devices built using this technology is is a large range. It allows you to record sound on the full spectrum of frequencies without trimming the upper or lower frequencies.
• Uniform Frequency Response. This property ensures the absence of distortion at the output of the device.

Reference. Frequency response - amplitude-frequency characteristic, it shows the dependence of the change in the amplitude of the signal in the frequency range. This characteristic should be the most uniform in order to avoid lowering the signal in one section and increasing in another. Since this distorts the very nature of the signal.

• The rate of change in the nature of the wave. A high value of this parameter avoids the loss of information during recording.

Minuses

• Demanding handling. Due to their structural properties, these microphones are extremely sensitive to the environment. High air humidity or temperature drop can change the sound quality due to distortion of the frequency response.
• Great influence of outside noise. Due to wide range recording, in addition to the useful signal, third-party noise. Often this problem is eliminated by the presence of an amplifier at the microphone output. However, with detailed processing, noise can be detected on the spectrum. To avoid this drawback recording should be done in a soundproofed room.
• High price. Quality devices are expensive to manufacture, and are quite expensive. At home, making a high-quality microphone is not possible.