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QuickTime Music Architecture

Q Is it possible to have four simultaneous voices?

A Yes, you can have four simultaneous voices.

Q What load do four voices place on the CPU of a 25MHz 68030 Mac?

A Four voices are not a problem for a 25MHz 68030 Macintosh. On a Macintosh LC, we have measured approximately 30 percent CPU usage using 5 voices.

Q Does the load level depend on the number of instruments used simultaneously?

A Yes. The actual load depends on how many instruments are playing simultaneously.

Q Can we build our own instruments? If so, is there a tool available for this purpose?

A In QuickTime 2.0, there is no way to add user- instrument files. However, you can embed instruments into QuickTime movies. Future releases will add Musical Instrument Extensions to your system folder.

Q Are the answers to all the above questions the same for the Windows version of QuickTime as they are for the Mac version?

A On a Windows machine, the music in QuickTime movies plays through a sound card, with MIDI hardware support, using the MIDIMAPPER driver, with very minimal CPU load.

Q Are the instrument sounds the same on Windows?

A The sound of the instruments can vary with the sound card installed.

Q Are most PC sound cards supported?

A The music in your movies will play on any PC sound card that supports MIDI playback under Windows.

[May 01 1995]

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