👉 A vocoder, also known as a signal-to-interference block (SIB), is a type of digital filter used in audio processing to reduce or remove noise from signals. It helps in achieving better quality and clarity by filtering out unwanted or interfering frequencies. The process involves applying a high-pass filter to the input signal, which removes low-frequency components that can interfere with the speaker's sound. Vocoder filters are often used in conjunction with other processing techniques such as equalization, phase modulation, or