AU to MMF — Format Comparison & Online Converter
Fast, instant AU to MMF (SMAF) conversion. No signup required. Just drop your .au file and get .mmf in seconds.
Batch Settings
在数字音频文件日益普及的今天，您可能会遇到各种格式转换的需求。AU文件，作为历史悠久的音频格式之一，常用于UNIX系统或一些专业的音频编辑软件中。而MMF，即Yamaha MA-1/MA-2/MA-3/MA-5格式，则在早期手机铃声和游戏音效中占据一席之地，尤其在多媒体功能相对简单的设备上表现出色。当您需要将这些AU音频内容，转换为更适应特定设备或场景的MMF格式时，我们的转换工具将是您的得力助手。无论是为了在老式手机上播放，还是集成到某些嵌入式系统中，我们都能帮助您高效、准确地完成转换，确保音质不受损耗，让您的音频文件在新平台焕发新生。
- 老式手机铃声制作
- 小型游戏音效嵌入
- 特定硬件设备兼容
MMF格式在2000年代中后期，曾是中国大陆、台湾及东南亚地区早期功能机市场非常流行的铃声和通知音格式。随着智能手机普及，其使用场景已大大减少，但仍存在于一些遗产系统或怀旧应用中。
About AU to MMF (SMAF) Conversion
AU and MMF are both audio formats, but they differ in important ways. AU is a widely used file format. MMF is a widely used file format.
When you convert AU to MMF, the goal is to convert between formats quickly. Converting AU to MMF maintains high quality with CocoConvert's optimised encoder settings. Understanding these technical differences helps you choose the right format for your workflow.
Your AU file is decoded and re-encoded as MMF. The conversion involves 4 steps: (1) your au file is uploaded and validated, (2) the file is decoded (parsed into its raw data), (3) the data is re-encoded in mmf 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 MMF file. For the opposite direction, CocoConvert also supports MMF to AU conversion.
How to Convert AU to MMF (SMAF)
- 1
Upload .au file
Select your AU file by dragging it to the upload zone or using the file picker. Batch upload is available for multiple files.
- 2
Choose .mmf
Set MMF as the output format. The converter uses optimal settings based on the AU→MMF conversion profile.
- 3
Convert
The server-side engine decodes your AU file and re-encodes it as MMF. Processing time depends on file size and complexity.
- 4
Download result
Grab your converted .mmf file. Multiple output files can be downloaded together.
What Happens When You Convert AU to MMF (SMAF)
Your AU file is decoded and re-encoded as MMF.
Your AU file is uploaded and validated
The file is decoded (parsed into its raw data)
The data is re-encoded in MMF format
The converted file is ready for download
Format Comparison
AU
.au file
| Extension | .au |
| MIME Type | audio/basic |
| Category | Audio |
MMF (SMAF)
.mmf file
| Extension | .mmf |
| MIME Type | audio/x-smaf |
| Category | Audio |
Should You Convert AU to MMF (SMAF)?
When to Convert
- ✓When you need a MMF file
Frequently Asked Questions
What is the difference between AU and MMF?
AU is a widely used file format. MMF is a widely used file format.
Does AU to MMF conversion affect quality?
Converting AU to MMF maintains high quality with CocoConvert's optimised encoder settings.
Which format has better compression, AU or MMF?
AU is a common audio format. MMF is widely supported. The better choice depends on whether you prioritize file size or quality.
How long does AU to MMF 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 AU or MMF better for long-term storage?
Both formats use lossy compression, so consider keeping your original source file for long-term storage.
Versions are pinned in our worker Dockerfile and re-built via CI on every change.