Virtual Composer is a multiple track graphical music sequencer acting as a QuickTime Musical Instruments interface for the Macintosh, designed for perfect execution of complex polyphonic music using QuickTime's Musical Instruments libraries or using custom SoundFont libraries to replace QuickTime's instrument waveforms.
Virtual Composer is mainly a musical renderer and sequencer and thus is predominantly performance-oriented. It is NOT a musical notator as it contains only a minimal (but sufficient) set of notation capabilities. If you want to quickly turn your doodles into printable music, this program is not for you.
Virtual Composer is mainly intended for performers who want to generate high quality musical executables. Playing is effected via QuickTime's internal Musical Instruments synthesizers or via SoundFonts so you don't need MIDI cables or external devices and all upsampling and downsampling is done automatically via QuickTime.
NOTE: The program gradually became obsolete when Apple switched architecture on its microprocessor and moved to Intel. It still works with some older versions of MacOS X, such as versions up to 10.1.3, however. If you have an older Mac with older versions of MacOS and you find that it works, contact me and I will send you a registration number for free.
The Help Manual is included with the download in .pdf format and describes the program's more elaborate program functions. You can read it here. You can view some screenshots here.
The projects below have been created by exporting Virtual Composer scores into AIFFs and then encoding them as .mp3s at 128/112 kbits and 44.1 kHz, using QuickTime's Musical Instruments version 4.1.2. Click on an project to download:
Depending on your System, you must download and install:
| CPU | OS1 | Application and Fonts2 | Supporting Files3 | QuickTime4 |
| 68k | MacOS 7.x | Virtual Composer 68k (350 KB) | Manual, Examples and Scripts (2.2 MB) | 4.0.3 |
| PPC | MacOS 7.x-9.x | Virtual Composer fat (410 KB) | Manual, Examples and Scripts (2.2 MB) | 4.1.2/5.x/6.x |
| PPC or Intel (up to 10.1.3) | OS X | Virtual Composer X (588 KB) | Manual, Examples and Scripts (2.2 MB) | 7.x |
1: The table above assumes that you are BOOTING into the indicted OS. The Virtual Composer applications are not guaranteed to work if you are booting into a different OS or if you use the applications in Classic mode emulation from OS X.
2/3: Downloading the application and fonts without the supporting files or the opposite (the supporting files without the application and fonts) will be an exercise in futility/frustration. You need to download BOTH, for the corresponding version of your OS.
4: You may need to install a different QuickTime version depending on your System configuration. For more details, consult the program manual.
5: The FAT application is basically identical to both 68k/PPC versions and is provided for people who don't know if they are running on a 68k or a PPC machine (it will run on both). If your machine is PPC, download the PPC version to minimize download times.
Latest version is 3.5.9, build #0 of 7/11/2005, for MacOS 9 and 3.6.1 of 7/11/2005, for MacOS X.
The unregistered version is fully functional except that you cannot save files in the program's internal format. You can still save in all other supported formats.
For the Classic version, Virtual Composer, you can use the registration number: M-62-Ff-98-Qw-95. If your system can still run MacOS 7-9, you can edit with the free Classic version and play with the OSX version, since files are interchangeable between both versions.
For the OSX version, Virtual Composer X, if you have an older Mac with older versions of MacOS (up to pre-Lion) and you find that it works, you can use the registration number: T-18-aB-13-ZX-98.
The author can be contacted here.