Audio converter for phone systems.
Convert existing recordings to WAV, MP3, G.711 A-law or µ-law. Choose your file and output format, then listen and download. Free, with no account required.
Which audio format do I need?Processed on converter.wolkano.io · Results available for 30 minutes · How we handle your files
No file handy yet?
Your phone system defines the right format.
Use the values from its import dialog or manufacturer documentation. Container, codec, sample rate and channel count must match. There is no single setting that works for every phone system.
| Output format | Audio properties | When to choose it |
|---|---|---|
| PCM WAV · 8 kHz | 16-bit, mono, linear PCM | When your import dialog requires exactly WAV, 8 kHz, 16-bit and mono. |
| PCM WAV · 16 kHz | 16-bit, mono, linear PCM | When the system supports 16 kHz for this announcement feature. |
| G.711a · RAW | A-law, 8 kHz, mono, no header | When headerless G.711 A-law is specifically required. |
| A-law WAV | G.711 A-law in a WAV container, 8 kHz, mono | When WAV with A-law is required. PCM WAV is a different export. |
| G.711u · RAW | µ-law, 8 kHz, mono, no header | When the requirement is µ-law or G.711u. |
| MP3 | Compressed audio; more settings in the format library | When your system accepts MP3, for example for music on hold. |
Using 3CX? The 3CX audio converter is fixed to PCM WAV, 8 kHz, 16-bit, mono. It also includes an audio comparison and an import guide.
Each format link selects the matching output. You can also share that selection with your telephony partner; the audio file is never included in the link.
Three checks before you go live.
1. Start with a good source file.
Use the original recording or a high-quality export. Repeated conversion can introduce further losses. Exporting as WAV cannot clean up a recording that already contains noise or clipping.
2. Listen to the actual output.
The preview is made from the finished output file. An 8 kHz telephony file sounds narrower than a studio recording. Check names, numbers, music levels and the beginning and end of your announcement.
3. Import it and make a test call.
Upload the file to the intended position in your phone system and activate it there. A test call checks the assignment, opening hours and transitions too. If an import fails, compare the export settings with the exact specification.
Audio converter questions.
Is the audio converter free?
Yes. Convert existing audio, preview the results and download them for free, without an account. To create a new AI phone announcement from your own text, use the generator separately: the preview is free and a finished announcement starts at €49 net.
Can I convert MP3 to 8 kHz, 16-bit mono WAV?
Yes. Choose your MP3 file and the PCM WAV output. This telephony preset produces linear PCM at 8 kHz, 16-bit, with one channel. Check that your system requires these exact values. Renaming the file extension alone does not convert the audio.
What is the difference between G.711a, A-law WAV and PCM WAV?
G.711a refers to the A-law codec. A RAW file contains encoded audio without a file header; A-law WAV puts the same codec inside a WAV container. PCM WAV contains linear PCM instead. Matching file extensions do not necessarily mean matching audio properties.
Which files and sizes are supported?
You can select WAV, MP3, M4A, AIFF, FLAC and OGG, among other formats. Each run supports up to five files, up to 50 MB and 15 minutes each, with a combined limit of 100 MB. Choose up to three output formats. RAW files require the correct input settings; missing metadata cannot be inferred reliably from the extension.
What happens to my recording?
Conversion runs on our service at converter.wolkano.io. Unused uploads are deleted after five minutes. Used originals are deleted when their associated jobs finish, no later than 30 minutes after upload completes. Results and previews are deleted 30 minutes after completion. “Delete files now” removes them sooner. Only upload files you are authorised to process.
Will conversion make my recording louder or better?
The level stays unchanged unless you edit it. You can explicitly trim, adjust gain, normalise the peak level or add fades. Conversion cannot restore lost audio detail. Listen to the finished output, then test the announcement through your phone system.