How to Convert AU to SOU — Quick & Free
Fast, instant AU to SOU conversion. No signup required. Just drop your .au file and get .sou in seconds.
Batch Settings
About AU to SOU Conversion
Short answer: yes, you can convert AU to SOU online for free, and quality is well preserved with the right settings. Just upload your .au file to CocoConvert, pick SOU as the output, and click Convert. The whole process takes seconds.
Now for the details. AU is a widely used file format. SOU is a widely used file format. Converting between these two formats lets you convert between formats quickly.
Your AU file is decoded and re-encoded as SOU. Converting AU to SOU maintains high quality with CocoConvert's optimised encoder settings.
CocoConvert runs entirely online — no software to install, no account to create. Your files are encrypted during upload (TLS), processed on isolated servers in Germany, and permanently deleted after 24 hours. It works in Chrome, Safari, Firefox, Edge, and all mobile browsers.
Need to convert more than one file? Free users can do 5 per hour. Pro gets 100 per hour with files up to 5 GB each.
How to Convert AU to SOU
- 1
1. Upload AU
Drop your .au file onto the page (or tap "Browse" on mobile). Add multiple files for batch conversion.
- 2
2. Select SOU
Choose .sou from the output dropdown. Settings are pre-configured for best results.
- 3
3. Convert
One click. The server handles all the heavy lifting using FFmpeg and Sharp.
- 4
4. Download
Your .sou file is ready. Download it directly or get all files as a zip archive.
What Happens When You Convert AU to SOU
Your AU file is decoded and re-encoded as SOU.
Your AU file is uploaded and validated
The file is decoded (parsed into its raw data)
The data is re-encoded in SOU format
The converted file is ready for download
Format Comparison
AU
.au file
| Extension | .au |
| MIME Type | audio/basic |
| Category | Audio |
SOU
.sou file
| Extension | .sou |
| MIME Type | audio/x-sou |
| Category | Audio |
Should You Convert AU to SOU?
When to Convert
- ✓When you need a SOU file
Frequently Asked Questions
Is AU to SOU conversion free?
Yes. CocoConvert offers free AU to SOU conversion with generous daily limits — 25 minutes of processing time and up to 5 files per hour (250 MB each). Pro plans remove these limits.
How fast is AU to SOU conversion?
Most files convert in 2–10 seconds depending on size. Large audio files may take 30 seconds. Batch jobs process in parallel for maximum speed.
What happens to my files after conversion?
Your uploaded AU file and the converted SOU file are both automatically deleted from our servers within 24 hours. They are never shared, sold, or analysed.
Does converting AU to SOU lose quality?
Converting AU to SOU maintains high quality with CocoConvert's optimised encoder settings.
Can I convert SOU back to AU?
Yes, CocoConvert supports SOU to AU conversion as well. However, if the original conversion involved lossy compression, converting back won't recover the lost data.
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