1. Home
  2. Audio Converter
  3. Convert AU to MMF

What is AU?

Sun AU is the native audio format for Sun Microsystems workstations, using simple mu-law encoding or uncompressed PCM.

What is MMF?

Synthetic Music Mobile Application Format (MMF/SMAF) is a ringtone format for feature phones, supporting melody and audio playback.

When Should You Use AU vs MMF?

Use AU When...

When legacy unix audio, sun workstation sound matters most, AU delivers. Its pristine output guarantees professional-grade results every single time.

Use MMF When...

Go with MMF when mobile phone ringtones, legacy polyphonic audio is on your mind. Its efficient encoding keeps things lean without sacrificing too much quality.

AU vs MMF: Key Differences

  • •AU uses lossless compression while MMF uses lossy compression — this is the fundamental technical difference between the two formats.
  • •Converting from AU to MMF changes compression type: lossy source becomes smaller but with some quality tradeoff.
  • •Alpha channel support: MMF lacks transparency support, so semi-transparent pixels from the source will be lost.
  • •File sizes: AU files typically range Small to medium, similar to WAV and MMF files Very small, under 100KB per ringtone.
  • •AU is optimized for legacy unix audio, sun workstation sound while MMF is designed for mobile phone ringtones, legacy polyphonic audio — choose based on your specific workflow needs

Advantages of AU

  • ✓AU uses lossless compression tailored for Legacy Unix audio, Sun workstation sound.
  • ✓AU is supported natively on virtually every device, browser, and operating system.
  • ✓AU files are bit-for-bit perfect, preserving every pixel and sample for professional work.
  • ✓AU integrates seamlessly with all major creative tools and workflows.

Advantages of MMF

  • ✓MMF uses lossy compression tailored for Mobile phone ringtones, legacy polyphonic audio.
  • ✓MMF is supported natively on virtually every device, browser, and operating system.
  • ✓MMF files are compact and quick to transfer, even over slow connections.
  • ✓MMF integrates seamlessly with all major creative tools and workflows.

Common Use Cases for AU to MMF Conversion

  • Streaming services
  • Audio books
  • Sound design
  • Language learning
  • Professional broadcasting
  • Video game audio assets

Industry Applications

Audio EngineeringLanguage LearningAccessibilityVoice-overAudio ArchivingGame Audio

Best Practices for AU to MMF Conversion

  • →Converting AU to MMF: MMF uses lossy compression — choose a higher bitrate (320 kbps) for near-CD quality
  • →Normalize audio levels before conversion for consistent playback volume
  • →MMF excels in professional audio workflows
  • →Always keep a backup of your original files before converting
  • →Choose the appropriate quality settings for your specific use case

Related Article

Video Compression Guide: Reduce File Size Without Losing Quality

Learn more about AU and MMF formats in our detailed guide.

Troubleshooting AU to MMF Conversion

  • !Clicks or pops in the converted MMF → sample rate conversion can introduce artifacts; use a clean multiple of the source rate
  • !MMF file has silence at the beginning or end → trim the source AU file before converting to avoid unnecessary padding
  • !Stereo image collapsed after converting AU to MMF → verify that the converter preserves channel mapping for multichannel audio
  • !The converted MMF clips or distorts at peaks → reduce the gain or apply a limiter before conversion to prevent hard clipping

Related Audio Converters

All Audio Formats

View all Audio converters →

More Audio tools

Convert to MMF →Convert from AU →

Convert AU to MMF Online - Free & Fast

Convert AU files to MMF online for free. High-quality conversion with no registration required.

Audio Converter

Upload or enter a URL to convert AU to MMF instantly

Click to upload or drag & drop AU file

or paste from clipboard

.au,.AU (max 100MB)

SSL EncryptedAuto-deleted in 1 hourProcessed securelyNo registration needed

Verifying security check…

About AU and MMF

AU

AU (AU audio) - Sun AU, legacy Unix audio format for Sun workstations. Best for legacy unix audio, sun workstation sound.

MMF

MMF (MMF ringtones) - SMAF, Synthetic Mobile Audio Format for ringtones. Ideal for mobile phone ringtones, legacy polyphonic audio.

Format Comparison

CompressionLossless → Lossy
TransparencyN/A
Use CaseConvert from legacy unix audio, sun workstation sound to mobile phone ringtones, legacy polyphonic audio
File Size~Very small, under 100KB per ringtone after conversion

FAQs

Is converting AU to MMF free?

Yes, GoConvertFile offers free conversion of AU to MMF for files up to 100MB. No registration required.

How long does it take to convert AU to MMF?

Most AU to MMF conversions complete within seconds for standard-sized files. Larger files may take longer depending on the conversion complexity.

What is MMF best used for?

MMF is ideal for mobile phone ringtones, legacy polyphonic audio. SMAF, Synthetic Mobile Audio Format for ringtones

Does converting AU to MMF lose quality?

Yes, converting AU to MMF uses lossy compression, which reduces file size by discarding some visual data. Set quality to 85-95% for a good balance of quality and file size.

What file size should I expect after converting AU to MMF?

MMF files are typically 50-80% smaller than AU files because MMF uses efficient lossy compression. The exact reduction depends on quality settings.

Related Tools

MP3 to AU
Convert MP3 to AU
MP3 to MMF
Convert MP3 to MMF
WAV to AU
Convert WAV to AU
WAV to MMF
Convert WAV to MMF
View all audio converter converters
Tune output for this audio conversion
80%