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Cervone.net Tech Files - Simple jOrgan setup on OS X


jOrgan is an open-source, free, virtual organ, which can be run on several platforms. Most of the people using it seem to be running Windows, and some of the Mac users have had trouble getting it to run, so I hope that these notes might be helpful. I have not done extensive testing with a lot of different configurations, so you may need to be adventurous in your own setup, but good luck!

I have used it successfully under 10.7 (Lion) and 10.9 (Mavericks) on an iMac and a recent MacBookPro. From the looks of it, the methods described here ought to work on Macs running recent versions of OS X. I have worked only with dispositions (the virtual organs made to run in jOrgan are called "dispositions") that are made for FluidSynth (see "basics", below), but I'm guessing if you run into a disposition that is intended for some other synth you may be able to figure it out in a similar way to what I did.


jOrgan requires its sounds to be played through a software synth of some sort. The dispositions I looked at were for FluidSynth, also an open source project. Fortunately, FluidSynth is included built-in to the OS X binary distribution of jOrgan, which was version 3.20 at the time of this writing [Fluidsynth can be installed and used as a stand-alone system, but that is an entirely different matter from what I have discussed here, and not necessary if all you are doing is trying to play organs through jOrgan].

To make the dispositions that I downloaded work on OS X, a few minor changes were necessary, as described below. You might want to try it out on a copy of the disposition called "fluidsynth-sample.disposition", which is supplied as part of the installation. If you can get this one to work, then you should be able to download other fluidsynth-based dispositions and have them work on your Mac.

Modifications to disposition files to make them play under OS X

IMPORTANT: These modifications worked for me but I cannot guarantee that they will work on your system. Use at your own risk, as I will not be responsible if they don't work for you, or cause some other pain. If they don't work, maybe they'll suggest something to you that will work for you, though.

I STRONGLY advise you to always work on copies of the original files so that in case something goes wrong, you can start over with a fresh copy.

OK - finally here's the fun part, and the guts of what makes the whole thing work!

  1. Open the disposition file that you want to play from inside jOrgan, or simply double-click the disposition file to open it (but if you are on Mountain Lion or Mavericks, or any version higher than 10.7 Lion, you might run into the situation discussed in the sidebar at the right).
  2. If it is the first time you have used this disposition, you may get a message saying that the disposition needs to be customised for your system and offering to let you do that now. The customisation is where you can assign inputs and midi channels to the various manuals and pedals in the organ (see my discussion of using jOrgan with Finale®, below) and you can do that later if you wish, as you can still test the functionality of the disposition using the jOrgan onscreen keyboard.
  3. go into "construct" mode by using the menu or clicking the icon: construct mode
  4. in the "elements" pane, look for something called "Fluidsynth Sound" and click it. In the "Fluidsynth-sample.disposition" file, it is at the root level of the elements list, but in more complex virtual organs it is often in a folder called "sounds" or "Sound Sources" [In some dispositions, it might be called something else, but it should still have the icon shown in the example below].
  5. in the "properties" section below, look for a property called "audio driver", it should be the fifth one down in the list. It may be blank, or may have a value. Click where the value should be and select "coreaudio" from the popup list (this is the crucial modification since coreaudio is the native sound system for OS X):
  6. leave construct mode by clicking the icon again, and save the disposition.
  7. now you should be able to test it back in play mode by clicking on keys in the onscreen keyboard - you should hear the corresponding sounds being played.

There is one other possible source of trouble that I have seen in some of the dispositions that I have downloaded, so if the steps above do not result in an instrument that plays from the onscreen keyboard, you may need to look further. Try going back into construct mode, and checking in the consoles folder, and look for an item with "connector" as part of its name, usually right at the top of the list. Click it and see what is next to "output" in the properties list. Sometimes it has something else there that may not exist on your system, but for Mac OS X it seems to work fine when left blank:

So at this point, your jOrgan disposition should be able to play through your system. However, you will still need to be able to route the MIDI data through to it. The way to do this will depend much on what kind of system you are using. At the moment, I do not have a MIDI keyboard or interface available to test with, although I have some ideas about how this might be done. I'll try to update this document later, when I am back in my regular location with the requisite equipment at hand. However, I have been able to make jOrgan work with the musical notation/playback program, Finale®. If you are interested in that approach, then read on!

Using jOrgan with Finale®

Finale® is a music notation and playback program, and jOrgan can easily be used as the playback instrument in Finale®, with the obvious set of advantages that jOrgan provides over the few organ sounds available in the stock Finale® installation. I have tested this method with Finale® 2012 under OS X 10.7 (Lion) and 10.9 (Mavericks), and would expect the procedure to be similar and to work as well with the various other combinations of recent versions of the two products.

Assuming that you have a working jOrgan disposition, as described above, here's the procedure to play Finale® scores through jOrgan:

  1. Do not open jOrgan yet (important), but run Finale® first, and open or create the score that you wish to play [NOTE: you should also be able to use jOrgan as the playback device for note entry after setting things up as described here].
  2. Select "Play Finale Through MIDI" from the "MIDI/Audio" menu:
    Play Finale through MIDI
  3. Select "Device Setup", then "MIDI/Internal Speaker Setup..." from the "MIDI/Audio" menu:
    device setup
  4. In the MIDI Setup window:
    • Set Playback To: "MIDI System"
    • Check the box to "Enable Inter-application Ports"
    • Set at least the first bank in the output section to one of the Finale 2012 Output channels (there are 4 to choose from). [NOTE: unless you are using a lot of Finale channels, you will probably only need to set the first bank, but you can set others if needed].
    • Click the "OK" button to save and close the window.

    MIDI setup window
  5. Select "Score Manager..." from the "Window" menu.
  6. In the ScoreManager window, set the device for each staff set to match what you chose in step 4. Also note the channel used by each staff set and change it if necessary:
    score manager
    Since each manual or pedal board of your jOrgan disposition could potentially be controlled by a different MIDI channel, you may wish to make finer adjustments to the MIDI channels used by Finale. If you open each staff set using the small grey disclosure triangle, you will see individual entries for each staff. It is possible to set a different channel for each staff here (and thus, use a different manual or pedalboard in the jOrgan disposition). Further, you can even set different channels for different layers on the staff for even more refinement (I don't think the "sound" or "Prg" values will matter in this case for basic playback):
    score manager
  7. Once the channels have been set to your satisfaction, close the ScoreManager window.
  8. At this point, I suggest saving the Finale score file so that these settings will be retained in the document, but leave Finale® running.
  9. Now run jOrgan and load the disposition that you want to use.
  10. Select "Customize..." from the "File" menu.
  11. The details of the Customize disposition window will vary depending on the specifics of the disposition in use, but in general, there should be one row for each manual and pedalboard, where you must set the device and channel for each to match the settings you made in Finale:
    Customize disposition
  12. It is not necessary to use the "Next >" button at this point, but go ahead and use it if you want to go to the following customisation screens to make other changes, then click the "Finish" button when ready.
  13. Save and close the disposition, and quit jOrgan [NOTE: You may find that on your system it is not necessary to quit jOrgan and reload the disposition, but in most cases, I have found that it will not play if I do not do this intermediary step].
  14. Reopen jOrgan and load the disposition, but do not do the customisation if asked.
  15. Now go back to Finale® and play the piece -- you should hear it through jOrgan!

I hope this page has helped you to get jOrgan running on OS X!

last updated:2014-01-01
update history:v-1.1 - Removed the Mavericks hack for the Gatekeeper message, and replaced it with the better and more general Gatekeeper procedure.

Gatekeeper Note

If you are running jOrgan under a version of OS X with Gatekeeper (10.8 and above), you might get a message saying that "jOrgan is damaged and can't be opened. You should move it to the trash".

The problem is that the Java stub used in the jOrgan binary distribution is unsigned, so Gatekeeper thinks it is from an unknown developer and wants to protect you from a potential danger. Since we trust jOrgan, we can temporarily disable the protection, teach Gatekeeper that this application is safe, then turn the protection back on.

NOTE: The protection provided by Gatekeeper is there for a good reason. Don't defeat it unless you know the implications of what you are doing, and are sure you can trust what you are trying to run, or beware the consequences, which can be dire!

That being said, here's how to fix the problem for jOrgan:

  1. select "System Preferences..." from the Apple menu.
  2. click the "Security & Privacy" button.
  3. if the lock in the lower left corner of the window appears locked, click it and authenticate with administrator user credentials.
  4. click the "General" tab if it is not already selected.
  5. in the section labelled "Allow apps downloaded from:", note the current setting, then click the radio button for "Anywhere".
  6. run jOrgan. If you get a message saying that the app was downloaded from the internet and asking whether you really want to run it, say to run it.
  7. back in the Security & Privacy window reselect the original option and close the window.
Now, you should be able to run jOrgan without getting any messages.