Microphones are an integral part of any studio. Moreover, no social event is complete without this device. But few people know that these devices can have a different design and different technical characteristics. It should immediately be said that the material will focus on such a device as an electrodynamic microphone. Although it does not provide the best sound quality.
Recognized leaders in this regard are condenser microphones. But due to their high cost, mass use at concerts and various events is impossible. They remain an expensive decoration for professional recording studios. Electrodynamic microphones are used always and everywhere. They may have some design differences, but the principle of action remains the same. So, let's talk about design features, technical specifications and the principle of operation of electrodynamic microphones. But first, a little history.
First microphones
During the nucleation of sound recording devices, electrodynamic devices were absent. The world's first microphones were completely carbon. Inside the device was a very fine coal powder, which only began to vibrate when a sound wave generated by the speaker’s voice reached it. Vibrations caused an electrical impulse and sound was transmitted further along the wires. It is worth noting that carbon microphones are still used in telephones, because only they can be so tiny that they fit in the handset of the device.
But carbon microphones did not last long in the field of sound recording. Soon there appeared devices operating according to the electrodynamic principle. They provided better sound.
The first electrodynamic devices for recording sound had a reel design and were distinguished by high sound quality (compared with coal counterparts). These devices were used at concerts, performances and rallies. Of course, the first microphones looked rather unusual: they were bulky devices with low sensitivity. As a result, the speaker had to almost kiss the microphone. But still it was a breakthrough.
After electrodynamics, capacitor devices appeared. They began to be massively used in professional recording studios. Because only they provided the highest quality sound.
But back to the electrodynamic devices and a more detailed analysis of the possible design options for the device.
Coil microphones
This design has been used from the very beginning. But even now, an electrodynamic microphone with a coil structure is widely used at various events. Its design is as follows: inside the device there is a coil of the thinnest wire with a permanent magnet. This design is covered by a diaphragm, which captures the vibrations produced by the speaker's voice. The membrane transmits vibration to the coil, which begins to oscillate and transmits vibration in the form of an impulse to the turns of wire. Further, the electric pulse goes through the modulator through the wires to the amplification device (amplifier) , where it is converted into a digestible sound. This design of the microphone is very reliable, since it contains the minimum number of mechanical parts subject to wear. Coil microphones are widely used at various events. But at concerts they try not to use them. Insufficient quality sound is obtained.
Ribbon Microphones
They appeared a bit later than reel and have design features that improve sound quality. The principle of operation is similar to reel models.
But there is a difference. Instead of a coil, the thinnest film of noble metals is used, which captures the smallest vibrations of the diaphragm, converts them into an electrical impulse and sends it further.
A distinctive feature of ribbon microphones in comparison with coil microphones is their markedly lower weight. These devices are widely used at concerts and various events of an appropriate scale, since they have a frequency range from 20 Hz to 20,000 Hz. An electrodynamic microphone with such a frequency range is also suitable for studio recording. That is why they are most widespread among professional musicians.
Microphone directivity
This feature directly affects sound quality. A directional microphone is capable of picking up the speaker’s voice only at a certain angle. This is only good if you don’t need to record many voices from one device.
Narrowly focused microphones are now used little. For their needs, professionals prefer microphones with a cardioid orientation. This means that the device is capable of recording everything that happens around it within certain limits. The trouble is that these properties are mainly possessed by capacitor devices. Electrodynamic devices with such characteristics exist in very limited quantities and are quite expensive. Most devices using the electrodynamic principle of operation are directional. And this is another minus addressed to them.
Microphone sensitivity
This characteristic shows how far from the membrane the device is capable of picking up sounds. But it depends not only on the microphone itself. An important role in this matter is played by the amplifier.
How to increase the sensitivity of the microphone? You need to choose a good amplifier or receiver that can fully reveal all the capabilities of the device. Another way is to replace the connecting wires. Quality wires are the key to high sensitivity. That is why many professionals prefer proven wired microphones to wireless stations. In the latter, the sensitivity and all other characteristics directly depend on the distance to the receiver. And wired models require only high-quality cords. They can be of any length.
Stereo microphones
This is a very interesting design, which includes one directional microphone and one cardioid located in one housing. Recording is carried out immediately by two devices, which allows you to get stereo audio output. Such microphones are very bulky. Therefore, they are used only at studios or radio stations. As sound recording devices, electrodynamic microphones can also be used.
However, manufacturers prefer capacitor models. They are easier to place in one case. However, electrodynamic models are also available. It's just that they are not so widespread. The microphone sound of this design is very high quality. An important plus can be considered a stereo mode.
The most famous manufacturers
Now, far from many companies produce high-quality electrodynamic microphones. This is a rather troublesome and resource-consuming affair. A good microphone for a studio can be found at companies such as Shure, Behringer, Sennhiser. Electrodynamic devices from Philips and Sony are also widespread. But they are only suitable for shouting in karaoke after a stormy feast. The most famous and trusted manufacturers is precisely the first trinity. But they only produce quality products for the needs of professionals. The sound of the microphone in this case plays a decisive role. And these companies have everything in order. No wonder professionals in the world of recording prefer products from these manufacturers.
Home Microphones
These devices are produced by almost all well-known manufacturers of consumer electronics. A review of microphones from the most famous brands (Sony, Philips, LG, VVK) suggests that these devices are capable of providing fairly high-quality sound during use. But they are not capable of recording a high-quality sound path. They can be used only with modern household DVD players in karaoke mode. They are also suitable for holding some celebrations (weddings, rallies, speeches, interviews). And in this case, the question of how to increase the sensitivity of the microphone does not arise, since this is impossible. These devices have a preset sensitivity. And to improve this characteristic is not possible.
Many devices of this class are wireless, which also adversely affects the sensitivity of the device. Be that as it may, such microphones are enough for home use. But for home studio equipment it is better to look for something a class higher.
Conclusion
So, we examined what an electrodynamic microphone is, its principle of operation and design features. This device is perfect for recording tracks, concert use, organizing public events. Entry-level models have proven themselves in home use. But for studio equipment it is better to choose a condenser microphone. It provides better sound quality and is characterized by a wide focus.