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64-bit Issues and Limitations in Max

The 64-bit implementation of Max is an exciting development for people creating patches with large memory requirements, but it comes with some limitations. These limits are based on underlying technologies that have either changed or are no longer available. We are actively working to resolve these issues, and future updates will improve the functionality of the 64-bit versions.


The primary change is Max’s use of QuickTime as a media layer for graphic and audio content: QuickTime is unavailable under 64-bit Windows, and has reduced functionality in 64-bit MacOS. Therefore, objects and functions that were based on QuickTime capabilities have to be rewritten to use other technologies. In the short term, this means that the following objects are not supported in our 64-bit versions:

  • jit.avc
  • jit.broadcast
  • jit.desktop
  • jit.displays
  • jit.qt.broadcast
  • jit.videoout
  • spigot~

The jit.qt.effect~ object is not suported on any version or platform starting with version 7.0 of Max.

The spigot~ object works only in conjunction with the jit.movie object with Quicktime selected as the video engine.


Codec support for the AVF engine is limited. The known supported codecs are:

  • H264
  • Photo-Jpeg
  • ProRes

Support for the AVF engine is limited on Apple OS 10.7.

There is limited support for reading non- JPG or PNG files under Win64 (e.g. PICT, TIFF, GIF, etc.)

The jit.movie object on Windows x64 is currently limited to DirectShow-supported movie files.

To support factory mp4 files on win-64, users should install Haali media splitter and ffdshow codec, as described here:


64-bit Windows no longer supports the “Microsoft Synthesizer” as a MIDI destination. The “Microsoft GS Wavetable Synth” should be used in its place.

Using the 64-bit Version

Windows 32- and 64-bit versions of Max are contained in separate installers. Externals for these versions have different extensions: .mxe for 32-bit and .mxe64 for 64-bit.

The MacOS installer is provided as a FAT bundle, and contains both 32- and 64-bit versions. When installed, the application defaults to 32-bit mode. To change this, select the application in the Finder and choose the “Get Info” menu option, then turn off the “Open in 32-bit mode” setting in the General tab.

Externals under MacOS are also FAT bundles, and contain both 32- and 64-bit versions of the underlying code.

3rd party external use is limited to the 32-bit version until the externals are converted into 64-bit equivalents by the developer. 32-bit externals cannot be used by the 64-bit version of the Max application.

See Also

Name Description
Technical Notes Technical Notes