Apple Final Cut Express HD - Manual (Page 568)

568 Part VIII Audio Mixing
Choosing an Audio Interface
An audio interface provides high-quality audio input and output between your computer
and audio equipment. This includes analog-to-digital (A-to-D) and digital-to-analog (D-to-
A) converters, a stable digital audio clock, and input connectors that are compatible with
your equipment, such as 1/4" phone (tip-ring-sleeve) and XLR connectors.
When you select an audio interface, make sure it has the following:
 Connectors that match your audio equipment, such as XLR, 1/4" TRS, RCA, or
TOSLINK (optical connector)
 Support for audio signal formats that your audio equipment uses, such as AES/EBU,
S/PDIF, or ADAT Lightpipe
 Enough audio inputs and outputs to connect your equipment
 Sample rate and bit depth at least as high as your audio equipment. For example, if
you have an audio device with a sample rate of 96 kHz and 24 bits, your audio
interface should at least match this.
Some PCI card audio interfaces include a breakout box. A breakout box allows you to
extend the interface’s audio connectors away from the back of the computer, such as
on a desk or even in an equipment rack.
The most common kinds of audio interfaces are described below.
Built-in Audio
For basic mixing, you can connect the built-in audio output on your computer to a pair
of external speakers. This gives you two output channels, which can be configured for
dual mono or stereo playback.
DV (FireWire)
If your sequence uses a DV codec, you can output audio via the FireWire port on your
computer. This allows you to use a DV deck, camcorder, or DV-to-analog converter as an
audio interface. In this case, you connect your FireWire cable to your DV device, and then
connect the audio outputs of the DV device to external speakers or a television monitor.
Third-Party Audio Interfaces
Third-party audio interfaces support more audio channels than your computer’s
built-in interface, and they often have professional connectors such as XLR or
1/4" phone (tip-ring-sleeve).
Important: If you are considering purchasing an interface, make sure it supports
Mac OS X Core Audio.