Why is it said that carbon microphones were a turning point in the history of microphones?

            Developed in the 1870s by Englishman David Edward Hughes, carbon microphones were the first reliable form of microphones. They were widely used for many years before being replaced by other types that showed better performance.

            Structurally, a carbon microphone comprises carbon granules within a small container that is covered by a thin metal diaphragm. It requires a battery to cause current flow. By compressing and decompressing the carbon, sound waves change the amount of electric current flowing through the wire. This, in turn, creates electrical waves.

            The biggest disadvantage of carbon microphones was that they had a limited frequency and would not reproduce music effectively.