To download OMS Emulator click here. Here is how to use it.

      First of all, what is this OMS Emulator. As you might know programs like sequencers use pieces of software that are responsible for the communication between the host program (i.e. DP) and other midi devices thru midi interface. DP uses its own FreeMidi and OMS (Opcode's Open Music System) is the other one used by Pro Tools, Reason and Logic to name just a few. Let's talk a little bit about Reason.

      Reason is a funny, little program that consists of different modules (synths, sample player, Rex player, drum machine and effects). It's a really fun program to play with and if you haven't discovered it yet, you should give it a try. You can program it and/or play in real time and when you do that you're controlling it from you master keyboard using ... OMS, of course. The next step forward would be to use it with DP so you can play it while you're sequencing.

      We already know that they use different midi communication programs so we have to find a way so they communicate with each other. If you go to the FreeMidi preferences window you will see the option "Use OMS when available" which means that your FreeMidi will communicate thru OMS with the outside world.

      Let's go back to Reason for a second. When you launch the program on its own, it uses OMS and audio it's routed to the sound card. What we really want is to be able to route audio to DP and record it, for example. This is how you do it: open DP first and then Reason. When Reason sees DP on its boot-up it will go to ReWire mode. ReWire is simply the mode where audio from Reason doesn't go directly to the sound card but it goes to DP and then out. This is all done internally on software level so you don't have to patch anything.

      Here is something noteworthy, DP's and Reason's controls are synchronized so when you hit play in DP, Reason will play too. Also when you change tempo in DP, Reason will follow it. Generally speaking, think about DP as your "master" and Reason as a "slave". Now, the only thing you have to do is create an Aux Track in DP and assign its input to Reason Mix 1&2.

      OK, so we took care of audio routing now let's go back to midi. Assuming that you set your FreeMidi pref to "Use OMS when available", when you go to assign an output of your midi track you should see your synths and IAC Busses. If you select one of the Inter Application Connection Bus and then set Reason to receive midi on this bus you should be able to play Reason instruments from DP. But it's kind of a hassle and your computer has to run four applications to handle it (DP, Reason, FreeMidi and OMS). What if we could get rid of one of them and maybe fool the computer that it's still there.

      Well, after this brief intro :-) now is the time to finally talk about OMS Emulator. What it does, as you might guess, it emulates OMS so we can still use the configuration described above but avoid dealing with OMS (which is not supported any more, by the way). This also means that the overall performance of the system is better, we will most likely encounter fewer crashes and the timing is tighter.

Instructions:

      When you download OMS Emulator make sure that you have the latest version of Stuffit Expander. Once you have it here is what you do. You go to your System Folder and find two folders: Extensions and Extensions (Disabled). Move you current OMS from Extensions to Extensions (Disabled) and place the OMS Emulator in the Extensions folder. Then, restart your computer. If you need to use programs that require OMS (i.e. Logic) make sure that you switch OMS Emulator with OMS. Now, go to FreeMidi configuration and FreeMidi preferences and check Inter-application MIDI. Open DP and next Reason. In Reason Audio Out you should see that it's in ReWire Slave Mode. Go to the Preferences, MIDI and set sequencer port and External Control Bus A to Digital Performer. On the top of the Reason virtual rack you will see MIDI In Device channels 1 through 16. This is where you can assign which channel will control which module. Go back to DP and on any midi track assign input to Reason 1 through 16 (these are your instruments in Reason). Record-enable the track, create an Aux Track and set its input to Reason Mix 1&2. Finally, you should be able to control Reason from within DP and have its audio playing an the Aux Track.

      Wow, this was supposed to be a short tutorial but it came out rather lengthy. I think that you will benefit more from it as opposed to an article that doesn't explain anything and just tells you do this, do that. If you don't understand something I'll be happy to explain it again and probably we will spend one of our meetings talking about these issues.
      Good luck and don't forget to let us know if you come up with a piece of good music. After all, that is what we really want to do isn't it?

          - Daniel Birczynski