SOX to AU — Format Comparison & Online Converter
Fast, instant SOX to AU conversion. No signup required. Just drop your .sox file and get .au in seconds.
Batch Settings
About SOX to AU Conversion
SOX and AU are both audio formats, but they differ in important ways. SOX is a widely used file format. AU is a widely used file format.
When you convert SOX to AU, the goal is to convert between formats quickly. Converting SOX to AU maintains high quality with CocoConvert's optimised encoder settings. Understanding these technical differences helps you choose the right format for your workflow.
Your SOX file is decoded and re-encoded as AU. The conversion involves 4 steps: (1) your sox file is uploaded and validated, (2) the file is decoded (parsed into its raw data), (3) the data is re-encoded in au format, (4) the converted file is ready for download.
CocoConvert's converter handles the entire pipeline server-side using FFmpeg, Sharp, and qpdf — battle-tested libraries used by streaming platforms and enterprise tools. Files are encrypted in transit and deleted within 24 hours.
This conversion is ideal when you When you need a AU file. For the opposite direction, CocoConvert also supports AU to SOX conversion.
How to Convert SOX to AU
- 1
Upload .sox file
Select your SOX file by dragging it to the upload zone or using the file picker. Batch upload is available for multiple files.
- 2
Choose .au
Set AU as the output format. The converter uses optimal settings based on the SOX→AU conversion profile.
- 3
Convert
The server-side engine decodes your SOX file and re-encodes it as AU. Processing time depends on file size and complexity.
- 4
Download result
Grab your converted .au file. Multiple output files can be downloaded together.
What Happens When You Convert SOX to AU
Your SOX file is decoded and re-encoded as AU.
Your SOX file is uploaded and validated
The file is decoded (parsed into its raw data)
The data is re-encoded in AU format
The converted file is ready for download
Format Comparison
SOX
.sox file
| Extension | .sox |
| MIME Type | audio/x-sox |
| Category | Audio |
AU
.au file
| Extension | .au |
| MIME Type | audio/basic |
| Category | Audio |
Should You Convert SOX to AU?
When to Convert
- ✓When you need a AU file
Frequently Asked Questions
What is the difference between SOX and AU?
SOX is a widely used file format. AU is a widely used file format.
Does SOX to AU conversion affect quality?
Converting SOX to AU maintains high quality with CocoConvert's optimised encoder settings.
Which format has better compression, SOX or AU?
SOX is a common audio format. AU is widely supported. The better choice depends on whether you prioritize file size or quality.
How long does SOX to AU conversion take?
Most conversions finish in seconds. Larger files or complex audio content may take 10–30 seconds. CocoConvert processes files in parallel for batch jobs.
Is SOX or AU better for long-term storage?
Both formats use lossy compression, so consider keeping your original source file for long-term storage.
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