What is analog dirt?
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Analog dirt is the distortion that results from the physical limitations of analog recording media. It is a type of noise that is introduced when a signal is transferred to a medium with a lower resolution. then the original. This noise manifests itself as a crackling, hiss, background buzz, or hum. Dirt is produced by electrical and mechanical components of the recording hardware and other physical sources such as vibrations in the room, microphone movement, and humidity changes due to weather.