Ribbon microphone

The mass of the diaphragm which includes coil assembly leads to poor frequency response in a moving coil microphone. Mechanical mass includes electrical inductance, and this produces loss in the form of attenuation at higher frequencies. To eliminate all these adverse things, a very light aluminium ribbon is used in place of diaphragm and coil assembly. This increases the frequency response for high audio frequencies. The ribbon is acting as a conductor as well as a diaphragm. The ribbon is placed in a magnetic field. This type of microphone is called ribbon microphone. Thus the ribbon microphone consists of only two parts-permanent magnet and ribbon conductor. The permanent magnet is a specially designed horse-shoe magnet with extended pole pieces which generates strong magnetic field. The ribbon is a light aluminium foil about 0.2 mg in weight, a few microns thick and a few mm wide. It is corrugated at right angles to its length. This provides greater surface area.