MIDIDevice Files (Common Elements)
MIDIDevice files are used on the Macintosh as a description of a MIDI device or MIDI instrument.
MIDIDevice files are found in the folder or subfolder of
These files contain xml format text which describes the MIDI devices in your system. If you currently have any of these files, you will usually find that there is one file per device manufacturer (eg. one file for Roland, one for Korg, one for Yamaha, and so on).
Since these folders are currently protected by the OS and require admin level security to access, when Midi Quest creates middev file containing information for an instrument, it stores that file in a sub folder of the Midi Quest data folder, the MIDI Devices folder to be exact. If you have created any midnam instrument name files on the Mac, you will find that this folder contains corresponding middev files for each instrument.
Why do I need these files?
In truth, hopefully you don't but here is why you may need them. Some sequencers (eg ProTools) use the middev information to access the midnam files and if the information isn't exactly right, the midname information will not be accessible.
How does it work?
Every midnam file includes Manufacturer and Model information. If the Manufacturer and model name you assigned to your MIDI device when it was added to the Audio MIDI Setup does not EXACTLY match that used by Midi Quest, the midnam information is not accessible. In most cases everything is probably fine. If you have a Korg M1, you likely set the manufacturer as Korg and the model as M1, which is what Sound Quest uses. However, in some cases, there might be a discrepancy. Is it a Roland MKS80, MKS-80, SuperJupiter, or "Super Jupiter"?
As a solution to this, Midi Quest Pro creates its own .middev file when a .midnam file is written. If you find yourself in a situation where the sequencer is unable to find the midnam file information you will need to do the following:
1. Open the manufacturer's .middev file in the /Library/Audio/MIDI Devices folder in a text editor
2. Open the instrument's .middev file stored in /users/<username>/Documents/Sound Quest/MidiQuestPro/MIDI Devices in a text editor
3. Copy the contents of the instrument .middev file into the manufacturer .middev file and save the manufacturer mididev file
4. You may need to close and re-open the AudioMIDI setup application for the additional MIDI devices to be accessible.
5. In AudioMIDI Setup, create a MIDI device definition using the newly added definitions.