Internal Objects

Internal objects include instruments located inside your Mac computer (such as software synthesizers and other musical applications). Although communication with sound sources inside the computer does not actually use MIDI, it still conforms to the MIDI communication protocol.

Internal objects have an input, but no output. They therefore act like extra output ports, which are hard-wired to the relevant sound generator (software instrument or application).

Apple QuickTime

The QuickTime system extension offers a software-based GM sound generator. The QuickTime Musical Instruments file must be present on your system.

To create a virtual representation of the QuickTime synth
  • Choose New > Internal > Apple QuickTime from the Environment’s local menu bar.

This software synth is 16-part multi-timbral. As usual, you can switch sounds via program changes; these are arranged according to the GM table. Channel 10 is always set to drum sounds, with GM key assignments. The QuickTime synthesizer reacts to notes and program change commands, as well as to pitch bend (volume controller #7).

The first note is used to initialize the relevant MIDI channel of the QuickTime synthesizer, and is not played.


You can use ReWire objects to send MIDI data to ReWire-compatible applications and their software instruments. To connect to a ReWire-compatible software instrument, first open Logic Pro and then the ReWire application. When shutting down, first quit the ReWire application, then Logic Pro.

You can use the Library to create ReWire objects automatically. (See Working with ReWire Applications.)

To manually create a ReWire object in the Environment
  • Choose New > Internal > ReWire.

Figure. ReWire object and its parameter box.

Apart from common parameters, the Rewire object offers three settings: