This is an audio file extension that allows for achieving surround sound. It is utilized in files of the DVD format. Its manufacturing company is Dolby Digital. An AC3 file is an audio stream that can be encountered as external soundtracks for films. You can download it separately and synchronize it with the movie file. The audio file contains 6 channels: upper and lower, front and rear, right and left, as well as low-frequency effects.

amr

AMR (Adaptive Multi Rate): adaptive encoding with variable bitrate

This information compression format allows for optimizing speech encoding. Files in the Adaptive Multi Rate format can be created using phones and smartphones. AMR files are mostly used for voice recordings. The main advantages of the format are the large number of encoding and decoding rates, as well as the small size of the resulting content. With the help of appropriate software, an Adaptive Multi Rate file can be converted into any other audio format.