To achieve good audio when recording we must take into account and know a number of specific features that will tell you that you have chosen a good microphone.
- The maximum sound pressure level. The maximum level the microphone can withstand without distorting the output sound, generally a good microphone supports 135dB SPL, unlike an excellent microphone that supports 150dB SPL.
- Self noise level. This is generated by air molecules impacting the microphone, the lower the sound generated the better the microphone.
- Signal to noise ratio. This is calculated by subtracting the maximum sound pressure level and self-noise level, which for example is 150dB SPL, and the noise level is 20dBA SPL, the signal-to-noise ratio is 130dB. The higher the ratio, the better the microphone.
- Sensitivity. The relevance of knowing this value we can know how good it is at picking up weak sounds and it is simply calculated by dividing 1 volt by µbar of pressure (1V/µbar). The values are always negative, the closer to 1 the better.
- Impedance. The importance of knowing this value is the internal resistance that the microphone will have as a function of its frequency. The best microphones have an impedance greater than 20,000 ohms.
- Saturation limit. There are no specific parameters to calculate it, it depends on the quality and way of manufacturing.
What is the best frequency for a microphone?
This refers to the frequency range from high to low, the frequency of microphones is calculated in Hertz, the frequency response of a microphone from about 80 Hz to 15 Hz, would be a very good choice.
Which is the most sensitive microphone?
We can say that the lower negative the more sensitive the microphone, for example, if its negativity is -31dB, while others are 36dB, we can say that the better is the one that reflects 31dB. The less negative the more sensitive it is.
Although, a quantum microphone capable of capturing the whispering of an atom has been invented, this far surpassed traditional microphones, but is not yet available on the market.
What is microphone noise?
This is produced when we speak or sing and expel the air and its particles impact the microphone membrane. It is specific to each microphone and basically cannot be eliminated. The lower its level, the better the microphone. You can say that 20dBA SPL is a good quality microphone, 30dBA SPL is intermediate and 40dBA SPL is a bad microphone.
What are the elements of a microphone?
Microphones, either wireless or wired, are composed of a series of elements that complement each other to capture sound and are as follows:
- Grille or Foam Filter.
- Body or Housing.
- On/Off button.
- Radio transmitter.