What is a AMR file?
AMR — mobile voice recording
Use the format AMR
A concrete example
Prepare an MP3 from a recording made on an old phone.
Useful checks
The frequency band of the voice can be reduced. A higher bitrate does not recreate the missing frequencies.
Choose a conversion
Keep the original and open the result in the software or on the device that will need to use it.
Your questions about this format
Which format should you choose to share a recording?
MP3 is a good starting point for sending or casual listening. Select your source, then MP3, start the conversion, and listen to the result. For audio editing, WAV may be more suitable but often produces a larger file.
Does converting an MP3 to a WAV improve the sound?
No: the WAV does not restore the information lost when creating the MP3. It mainly allows you to change the working format. To preserve the maximum quality, start from the original recording when you have it.
How can you compare before downloading?
After a successful audio conversion, use the original and resulting players. Check a quiet area and a loud area, then the beginning and the end. In case of cutoff or absence of sound, keep the original and report the formats used to support.
Why doesn't a MIDI file sound exactly like it does on my system?
A MIDI describes notes and instruments, not a sound recording. Its conversion depends on the sound bank used by the engine. Listen to the rendering before broadcasting; the MIDI synthesis is part of specialized NoLimit processing.
What is it?
AMR is a format built for one purpose only: the human voice over a phone line. It compresses audio down to a handful of kilobits per second, keeping only the frequencies that carry speech.
Applied to music, the results are dismal — anything that isn't a voice gets mangled beyond recognition. That's expected: it was never designed for that job.
History & origin
AMR was adopted in 1999 by the standards body governing mobile telephony, to carry voice over GSM networks.
It later found its way into voice memos and audio messages on phones from before the smartphone era.
Why it is useful
Files are tiny: an hour of speech fits into just a few megabytes.
It remains perfectly intelligible for what it's meant to do — carry a voice, nothing more.
Limits & drawbacks
Audio quality is very poor, making it unusable for music.
It's an aging format, poorly supported by modern desktop software.
Practical tips
Convert your AMR files to MP3 so you can listen to and archive them comfortably — but don't expect to recover a level of quality that was never in the original file to begin with.
For modern voice recording, Opus does a far better job at a comparable file size.
Convert your AMR in seconds, on our secure servers in France.
Convert a AMR