To convert audio, follow these steps:
- Use the "Local file" or "Online file" buttons to specify how to upload the audio to the server. Use the "local file" if you need to convert a file from your computer, in order to specify a file on the Internet, select "Online file" and in the appeared field paste the link to the file. We do not set any limits on the size of the audio file, but the larger the file, the more time it will take to convert. Just be patient and everything will turn out. You can convert files from audio or video formats. For formats that support tags, the data will also be transferred.
- To start the conversion, click the "Convert" button to start the transformation. If the conversion is successful, the file will be available in the "Conversion Results" section. If you just need to download a file, click on the file name. If you want to get other ways to save, then click on the icon to generate a QR code to upload the result to your mobile phone or tablet, and also if you want to save the file in one of the online storage services such as Google Drive or Dropbox.
Please be patient in the conversion process.
Compare AMR with AAC
| Format introduction | The Adaptive Multi-Rate (AMR or AMR-NB or GSM-AMR) audio codec is an audio compression format optimized for speech coding. AMR was adopted as the standard speech codec by 3GPP in October 1999 and is now widely used in GSM and UMTS. | Advanced Audio Coding (AAC) is an audio coding standard for lossy digital audio compression. Designed to be the successor of the MP3 format, AAC generally achieves better sound quality than MP3 at similar bit rates. AAC has been standardized by ISO and IEC, as part of the MPEG-2 and MPEG-4 specifications. |
| Technical details | AMR speech codec consists of a multi-rate narrowband speech codec that encodes narrowband (200-3400 Hz) signals at variable bit rates ranging from 4.75 to 12.2 kbit/s with toll quality speech starting at 7.4 kbit/s. Sampling frequency 8 kHz/13-bit (160 samples for 20 ms frames), filtered to 200-3400 Hz. | AAC supports inclusion of 48 full-bandwidth audio channels in one stream plus 16 low frequency effects channels, up to 16 "coupling" or dialog channels, and up to 16 data streams. The quality for stereo is satisfactory to modest requirements at 96 kbit/s in joint stereo mode; however, hi-fi transparency demands data rates of at least 128 kbit/s. |
| File extension | .amr, .3ga | .aac |
| MIME | audio/amr | audio/aac |
| Developed by | 3GPP | Bell Labs, Fraunhofer Institute etc. |
| Type of format | Audio compression format | Audio compression format |
| Associated programs | Audacity, FFmpeg, MPlayer, QuickTime, VLC media player | foobar2000, AIMP, DirectShow, QuickTime, VLC media player. |
| Wiki | https://en.wikipedia.org/wiki/Adaptive_Multi-Rate_audio_codec | https://en.wikipedia.org/wiki/Advanced_Audio_Coding |