What is vocoding?

Vocoding, also known as voice coding or voice compression, is a technique used to modify or manipulate a person's voice. It refers to the process of encoding the characteristics of a voice signal, such as pitch, timbre, or formant frequencies, and then decoding it to alter the original sound.

The concept of vocoding originated in telecommunications and was primarily used in radio communication systems, where it helped reduce the bandwidth required for transmitting voice signals over limited channels. Today, vocoding is widely employed in various disciplines, including music production, speech synthesis, sound design, and even in popular culture, with the use of voice changing software and effects.

Vocoders work based on the principle of analyzing two different signals: the carrier signal and the modulator signal. The carrier signal is typically a synthesized or prerecorded sound, while the modulator signal is the voice or sound input that needs to be modified. The carrier signal provides the overall structure and characteristics, while the modulator signal imparts its vocal qualities to the output.

Using a bank of filters, vocoders extract the specific spectral information from the modulator signal and apply it to the carrier signal. This process ensures that the output sound has the pitch and timbre of the modulator signal while retaining the structural framework of the carrier signal. The result is often a unique and synthesized voice that combines both signals in an interesting and creative way.

In music production, vocoders are frequently used to create robotic or synthesized vocals, popularized by artists like Daft Punk or Kraftwerk. They can also be employed to blend a vocal track with an instrumental or to add harmonies to a lead vocal. Additionally, vocoders have found applications in speech synthesis, allowing computers and artificial intelligence to imitate human voices, as well as in telecommunications to compress voice signals for efficient transmission.

Overall, vocoding is a powerful technique that alters and manipulates the characteristics of a voice or sound, making it a versatile tool for various industries, including music, entertainment, and telecommunications.