Audio conversion device
Sometimes shortened to ACD, an audio conversion device is a hardware mechanism that converts an analog signal into a digital one. For instance, users may want to store or play an analog audio source (cassette tape) on a computer and other electronic media devices (like a smartphone). The device shown in the image, a cassette-to-USB converter, was made specifically for this purpose.
There are different types of these devices available, but they each perform a similar function: transform audio from one format to another. Common types of audio conversion devices include cassette tape to MP3, LP (long play) record to MP3, and audio CD (compact disc) to MP3 as these are technology types users want to convert.
Most modern audio conversion devices connect via a USB (universal serial bus) port on a computer, but some use an optical out as well. The software included with the device records the audio playback from the media and converts it to MP3 format, but some devices support other formats. There are multiple companies that build and sell these devices, including DB Tech, Ion, and Jensen.