Apple Logic (1.1) - Manual (Page 67)

Chapter 7 Mixer, Instruments, and Effects 67
The cabling between Audio Objects—which deals with the audio signal flow—is
automatically and invisibly connected by Logic, as new Audio Objects are created and
assigned. This invisible cabling follows a fairly standard signal path, normally found on
a mixing console with audio channels, busses, master faders, and so on. As such, the
Logic mixer will immediately be familiar if you’ve had any experience with mixing
consoles.
This section describes the most important Audio Object types, and what they are used
for.
Audio Track Object
The Audio Track Object is, as mentioned, the fundamental Object used for audio
functionality in Logic’s Environment. By default, any Audio Object created will be
assigned to the first available playback channel, or Audio Track. An Audio Track Object
is used to record and play back Audio Regions on the corresponding track in the
Arrange window.
Audio Instrument
This Audio Object supports the use of software-based instrument plug-ins. These plug-
ins include those that are built into Logic, plus third-party Audio Unit instruments.
Although the Audio Instrument Object looks similar to Logic’s other Audio Objects, it
supports MIDI note input, which the others do not. This enables appropriate plug-ins to
be played via MIDI, just like an external MIDI synthesizer, sampler or module. The
corresponding Audio Instrument tracks in the Arrange window allow you to record and
play back MIDI Regions.
Bus Object
Signals from various Audio Objects can be mixed to a Bus Object, which is the software
equivalent of a bus/group on a hardware mixing console. One or more effects are often
inserted in a bus. In this scenario, the bus acts as both an effect unit and a return
channel strip simultaneously.
A Bus Object also acts as a “group” fader, where multiple audio channels can be routed
to it, allowing volume or pan to be globally adjusted for all grouped channels by
adjusting these parameters on the Bus channel strip. Busses can be routed to Output
Objects (Master Faders) or to other Bus Objects.
Output Object
This is Logic’s Master Output Object, equivalent to the master output faders on a
mixing desk. If your audio interface features multiple outputs, you can set up an Output
Object for each physical output—or output pair. This fader type features a Bounce
button (labeled Bnce) which is used to bounce (digitally combine, or mix) any incoming
audio—from the other fader types—to a mono, stereo or multiple Surround (Logic Pro
only) format audio files.