Sample Files
Details
Mobile Music File
About
MMF is a lightweight audio format used mainly for mobile ringtones, notification sounds, and embedded system audio. It is part of Yamaha’s SMAF specification and is optimized for very small file sizes.
History
MMF (also known as SMAF) is a mobile audio format developed by Yamaha Corporation in the early 2000s. Designed primarily for ringtones, system sounds, and interactive audio on mobile phones, MMF provided compact file sizes suitable for devices with limited storage and processing capability. SMAF supported both synthetic music using Yamaha’s MA sound chips and encoded audio such as ADPCM, making it ideal for early feature phones and downloadable ringtone services popular before the rise of smartphones.
Learn more at: https://www.yamaha.com
Extremely small file sizes ideal for mobile devices
Supports both synthesized music and ADPCM-encoded audio
Optimized for low-power embedded hardware
Used widely in early mobile ringtone ecosystems
Efficient looping and control for interactive audio playback
Load MMF files onto compatible feature phones for ringtone playback
Convert MMF files to MP3, WAV, or M4R for modern devices
Use in embedded applications requiring compact audio assets
Test legacy ringtone or alert systems for compatibility
Use Cases
Here are the use cases for this file extension
Mobile Ringtones
Originally one of the most popular formats for downloadable ringtones on feature phones.
Device Notification Sounds
Used for system alerts, UI sounds, and embedded audio cues.
Embedded Systems
Suitable for handheld devices, toys, and gadgets requiring tiny audio assets.
Compatibility
This extension is compatible with the following platforms.
Older Mobile Phones (native)
Windows (via software tools)
macOS (conversion required)
Linux (conversion required)
Android (requires conversion)
iOS (requires conversion)
More Details
Here are some technical details about this extension
File Extension
.mmf
MIME Type
application/vnd.smaf
Container Format
SMAF (Synthetic Music Mobile Application Format)
Audio Support
ADPCM, MA-3/MA-5 synthesis data
Typical Duration
Often 5–30 seconds (for ringtone use)
Metadata Support
Limited (mainly SMAF control data)
Typical Use
Mobile ringtones, system alerts, embedded audio
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