🎵 Minimum requirements for audio files
What audio file formats are supported?
Two audio file formats are supported: WAV and MP3. It is important that your audio files meet the minimum technical requirements listed below, otherwise the file may not play correctly or be rejected by the system.
What are the requirements for WAV files? 🎙️
WAV files are the recommended format as they offer the best audio quality. The following encoding types are supported:
Option 1 — PCM (best quality)
Setting | Value |
|---|---|
Channels | 1 (Mono) |
Sample Rate | 16,000 Hz |
Precision | 16-bit |
Bit Rate | 256k |
Sample Encoding | 16-bit Signed Integer PCM |
Option 2 — u-law
Setting | Value |
|---|---|
Channels | 1 (Mono) |
Sample Rate | 16,000 Hz |
Precision | 14-bit |
Bit Rate | 128k |
Sample Encoding | 8-bit u-law |
Option 3 — A-law
Setting | Value |
|---|---|
Channels | 1 (Mono) |
Sample Rate | 16,000 Hz |
Precision | 13-bit |
Bit Rate | 128k |
Sample Encoding | 8-bit A-law |
Option 4 — GSM
Setting | Value |
|---|---|
Channels | 1 (Mono) |
Sample Rate | 16,000 Hz |
Precision | 16-bit |
Bit Rate | 26k |
Sample Encoding | GSM |
What are the requirements for MP3 files? 🎧
Setting | Value |
|---|---|
Channels | 1 (Mono) |
Sample Rate | 16,000 Hz |
Precision | 16-bit |
Bit Rate | 24k |
Sample Encoding | MPEG audio (layer I, II or III) |
Why does the audio file need to be Mono (1 channel)? 🔈
Telephony systems use a single audio channel (mono). Stereo files (2 channels) are not supported and may cause playback issues or be rejected. Always make sure your audio file is exported or converted to mono before uploading.
Why is a Sample Rate of 16,000 Hz required?
A sample rate of 16,000 Hz (16 kHz) is the standard for telephony audio. It provides sufficient voice quality for phone calls without unnecessarily large file sizes. Higher sample rates (such as 44,100 Hz used in music) are not needed and may not be processed correctly.
How do I convert my audio file to the correct format? 🛠️
If your audio file does not meet the requirements, you can convert it using free tools such as:
Audacity (free, Windows/Mac/Linux) — audacityteam.org
FFmpeg (command-line tool for advanced users)
Online converters — search for "WAV converter mono 16kHz"
💡 Tip: When exporting from Audacity, set the sample rate to 16,000 Hz, select Mono, and choose the correct encoding before saving.
⚠️ Important: Files that do not meet the minimum requirements may not upload correctly or may cause playback issues. When in doubt, use WAV with 16-bit PCM encoding — this is the most widely supported and highest quality option.