http://support.apple.com/en-us/HT200269
MainStage 3.1 includes the following changes. For more information, see http://www.apple.com/logicpro/mainstage.
New Features and Enhancements
* Redesigned Compressor plug-in with scalable, Retina-ready interface and a new compressor model.
* Retro Synth can now create wavetables from imported audio and is able to stack up to 8 voices.
* The Plug-in Manager now allows you to customize the organization of your menu.
* Expanded sound library includes over 200 new synth patches and 10 Mellotron instruments.
* New Auto Sampler plug-in converts hardware synthesizers into sampled instruments.
* Custom shortcuts can be assigned and managed using the new Key Command editor.
* It is now possible to copy and paste ranges in the layer editor.
MainStage 3.1 includes the following changes. For more information, see http://www.apple.com/logicpro/mainstage.
New Features and Enhancements
* Redesigned Compressor plug-in with scalable, Retina-ready interface and a new compressor model.
* Retro Synth can now create wavetables from imported audio and is able to stack up to 8 voices.
* The Plug-in Manager now allows you to customize the organization of your menu.
* Expanded sound library includes over 200 new synth patches and 10 Mellotron instruments.
* New Auto Sampler plug-in converts hardware synthesizers into sampled instruments.
* Custom shortcuts can be assigned and managed using the new Key Command editor.
* It is now possible to copy and paste ranges in the layer editor.