Microphones & Loudspeakers
M.L. Anand · 2021
Microphones and Loudspeakers are essential components of almost all audio video systems. The important characteristics of microphones are Sensitivity, Signal/Noise Ratio and Directivity. Mikes can be classified as under: Pressure Microphones and Pressure gradient microphones. A protective cover is used to save diaphragm and coil assembly against mishandling. The crystal microphone works on the principle of piezo-electric effect. According to this effect, crystals of few materials, when applied pressure, start producing “vibrations” or “oscillations”. Crystal microphone makes use of crystals of Quartz, Roschelle salt, or of Ammonium dihydrogen phosphate, as these materials give better results. The moving coil microphone studied previously, is heavy due to its diaphragm, coil and magnet. There is no major difference between cone and horn type speakers, except that the cone has been replaced by a horn to get more audio output, as a horn provides better impedance matching with the surrounding air.