Files with the .ac3 filename extension refer to the proprietary audio file format Dolby digital AC-3, developed by Dolby Laboratories. The AC-3 format is from the lossy family of audio compression formats. It supports a variety of audio channel configurations and was the first of its kind to support the full surround sound experience. Because of this, the format has been commonly used in the development of motion picture features designed for theaters and in consumer homes through DVDs and surround sound home theater systems. The AC-3 format is one of the supported audio codecs of the ATSC standard ' a set of standards developed for digital television transmission in several affiliated countries.
The .amr filename extension refers to the adaptive multi-rate audio codec initially released in 1999. The format is typically used to encode speech audio and is optimized for this purpose. It can encode speech into one of two file version, either AMR-NB (narrow Band) or AMR-WB (Wide Band) which supports a broader frequency. Because of its optimization for speech audio, the format has been widely adopted as the standard speech codec for GSM and UMTS mobile phone networks by the 3rd Generation Partnership Project ' a collaborative group of organizations in the telecommunications industry.
FreeFileConvert uses tuned encoding for AC3 to AMR conversions, preserving clarity while trimming file size. Finished audio streams instantly across phones, tablets, desktops, and modern browsers without extra tweaks.
Upload AC3 files from desktop, tablet, or cloud storage, queue multiple jobs, and let the converter finish autonomously. Return whenever convenient to download synchronized AMR results on any device you rely on.
Process up to 5 files sized 1000 MB per batch without splitting queues manually. Mixed-format uploads convert together, producing consistent AMR audio with dependable progress tracking.
The AC-3 audio encoding format supports between one and six channels with frequency ranges from 20 hertz to 20 kilohertz. The format contains frame headers which detail information about the rate of sampling, encoded channels, bit-rate among other details. It also consists of six audio blocks.
AMR format encodes narrow band signals between 200 and 3400 hertz at a maximum bitrate of 12.2 kilobits per second. The format employs the ACELP ' Algebraic code-excited linear prediction algorithm, a proprietary speech encoding method created by the VoiceAge Corporation.
Upload your audio file in the AC3 format from your device, Dropbox, or Google Drive.
Select AMR as the output format and click Convert. Adjust optional settings if needed.
Download the converted audio file. Each file stays available for up to 5 downloads.