KAR is the original format of audio files for creating karaoke, which are formed in a variety of software systems. It has the ability to save not only MIDI file data, but also lyrics. The KAR format is part of the .midi extension. In most cases, they are used as a source for adding special text to regular MIDI files, and they also differ from the Karaoke file. After all, there is no additional track with words that are synchronized with the main melody according to certain algorithms. As a rule, in order to realize the vocal part, you must apply the first track. For a stream of words, a second track is used. This file extension can be obtained using specialized software. But not only. It can also be created using MIDI keyboards that are connected to computer hardware. If there are appropriate plugins, then you can open the KAR file using the Media Player traditional for the Windows operating system. Anyone using the Mac OS platform can play KAR files in the Mireth Technology Music Man karaoke application. But the universal option for this pair of systems is PG Music Band-in-a-Box. This software is the most popular among analogues. Together with the .KAR extension, they sometimes provide reference data on where audio catalogs and item metadata associated with audio tracks are located. It is also possible that there is information about the artist and about the albums.
AMR is a sound file format with a specific focus. Created a long time ago, before the advent of MP3. some sources call the developer Ericsson. The name of the format is an abbreviation for Adaptive Multi Rate. Sound files of this format are intended for mobile devices and in GSM cellular networks. Using this format provides a small file size due to the technology of signal coding in the speech frequency range. Effectively compressing audio recordings of human speech makes this format often used in voice recorders on mobile phones, for voice recordings, and for MMS messages.