Microphone: Definition and Types

What are the types of microphones?

The types of microphones are varied and include condenser microphones, dynamic microphones, and ribbon microphones.

• Condenser Microphones: These microphones use a conductive diaphragm and an electrically charged backplate to form a sound-sensitive capacitor. They are known for their sensitivity and wide frequency response. Condenser microphones are commonly used in studio recording due to their high-quality audio capture.
• Dynamic Microphones: Dynamic microphones operate based on electromagnetic induction principles. They are robust and can handle high sound pressure levels, making them suitable for live performances and recording loud sound sources like drums and guitar amplifiers.
• Ribbon Microphones: Ribbon microphones work by air movement associated with sound waves moving a metallic ribbon in a magnetic field, generating an imaging voltage between the ends of the ribbon. They are known for their warm and natural sound reproduction, often used in broadcasting and studio recording for vocals and instruments.

Each type of microphone has its own unique characteristics and applications, catering to different recording needs and environments.

Condenser Microphones

Condenser Microphones are a type of microphone that operate based on the principle of capacitance. They are designed with a conductive diaphragm placed close to a backplate, forming a capacitor where the diaphragm acts as one plate and the backplate as the other. This setup creates an electrical charge, and when sound waves hit the diaphragm, it vibrates, causing the distance between the diaphragm and backplate to change, thus altering the capacitance and generating an electrical signal.

Condenser microphones are known for their sensitivity and ability to capture detailed audio with high fidelity. They are commonly used in studio recordings, live performances, and other applications where capturing subtle nuances in sound is crucial. Due to their design, condenser microphones require power to operate, which can be provided through an external power source or through phantom power supplied by mixing consoles or audio interfaces.

Inventors and important figures related to condenser microphones include E. C. Wente and Albert Thuras, who made significant contributions to the development of condenser microphone technology. Condenser microphones are often preferred for their wide frequency response, low noise levels, and superior transient response, making them a popular choice in professional audio recording and broadcasting settings.

Dynamic Microphones

Dynamic Microphones are a type of microphone that operate on the principle of electromagnetic induction to convert sound waves into electrical signals. They consist of a diaphragm attached to a coil of wire, which moves in response to sound pressure variations. This movement induces a current in the coil through electromagnetic induction, generating the electrical signal that represents the captured audio. Dynamic microphones are known for their robustness and ability to handle high sound-pressure levels, making them suitable for capturing loud sources without distortion.

One of the key features of dynamic microphones is their low sensitivity compared to condenser microphones. This lower sensitivity means that dynamic mics are less likely to pick up unwanted background noise or feedback, making them ideal for live performances or recording in noisy environments. The design of dynamic microphones also allows them to roll off some of the high-end frequencies, which can help in reducing room sound and reflections that may affect the audio quality.

Dynamic microphones are commonly used in various applications such as live sound reinforcement, broadcasting, recording loud instruments like drums and guitar amplifiers, and capturing high sound-pressure level sources. Their ability to handle loud SPL (sound-pressure levels) is attributed to the structure of the transducer, which typically consists of a small coil that moves within a magnetic field to generate the electrical signal.

In terms of inventors and important figures, the dynamic microphone was not attributed to a single individual but has evolved over time through contributions from various engineers and inventors in the field of audio technology. The acronym “dynamic mic” is often used as a shorthand term for dynamic microphones in the audio industry.

Dynamic microphones are a type of microphone that utilizes electromagnetic principles to convert sound waves into electrical signals. They are characterized by their durability, ability to handle high sound-pressure levels, and lower sensitivity compared to condenser microphones, making them suitable for a wide range of audio applications.

Ribbon Microphones

Ribbon Microphones are a type of microphone that falls under the category of dynamic microphones. They utilize a thin membrane or strip of metal, often made of aluminum, suspended within a strong magnetic field. This design allows ribbon microphones to capture sound by converting acoustic energy into electrical signals through the movement of the metal ribbon within the magnetic field. The concept of ribbon microphones aligns with the fundamental principle of microphones as transducers, converting sound waves into electrical signals that can be processed by electronic devices.

One distinctive feature of ribbon microphones is their bidirectional polar pattern, meaning they pick up sound equally well from both the front and back of the microphone. This characteristic makes ribbon microphones suitable for capturing a wide range of audio sources, including instruments, vocals, and ambient room sounds. The bidirectional nature of ribbon microphones is a key attribute that sets them apart from other microphone types and contributes to their versatility in recording applications.

Ribbon microphones are known for their durability and robust construction. They are often described as some of the most durable microphones available, capable of withstanding various environmental conditions and handling high sound pressure levels. This durability makes ribbon microphones a reliable choice for recording instruments like guitars, drums, brass, strings, and capturing room ambience. The design and construction of ribbon microphones reflect their role as essential components in audio recording and broadcasting setups, highlighting their importance as specialized transducers in the audio industry.

Historically, ribbon microphones have played a significant role in audio technology development, with inventors and companies like RCA contributing to their advancement. The design of ribbon microphones, with a metal ribbon suspended in a magnetic field, showcases the innovative approach to capturing sound and converting it into electrical signals. The unique characteristics of ribbon microphones, such as their dark tone and low output requiring additional gain, demonstrate their distinct sonic qualities and the technical considerations involved in using them effectively in recording scenarios.

What is the history of microphones?

The history of microphones is starting with the early developments in the 19th century. In 1827, Sir Charles Wheatstone coined the term “microphone,” although the first practical modern microphone was patented by Emile Berliner in 1876. Berliner’s invention, the carbon microphone, marked a significant advancement in sound engineering. Alexander Graham Bell recognized the importance of Berliner’s technology and purchased the patent for $50,000 in 1877. Following Berliner’s invention, Alexander Graham Bell patented the first microphone in 1876, which utilized a wire conducting direct current (DC). This invention was crucial in the development of telecommunications and sound recording technologies. The microphone played a pivotal role in enabling the transmission and recording of sound, starting with Bell’s electro-magnetic microphone. In 1916, E.C. Wente invented the condenser microphone at Western Electric, also known as a capacitor or electrostatic microphone. This innovation further improved sound quality and sensitivity in recording and broadcasting. The condenser microphone was a significant milestone in the evolution of microphone technology. In 1964, Bell Laboratories introduced the electret microphone, revolutionizing the microphone industry with its improved performance and efficiency. This invention transformed the way microphones were designed and manufactured, offering enhanced capabilities for various applications. Throughout the years, advancements in microphone technology have led to the development of various types, including the ribbon microphone in 1942, which was designed for radio broadcasting. The microphone industry has seen a wide range of innovations and improvements, from the early carbon microphones to modern electret and condenser microphones. The history of microphones is a testament to the continuous research and advancements in sound engineering, enabling the conversion of sound waves into electrical signals for communication, recording, and broadcasting purposes.