Usb audio interfaces – Apple Soundtrack Pro 3 User Manual
Page 512
USB Audio Interfaces
There are a wide variety of USB audio interfaces available. USB supports plug-and-play
operation and the ability to connect several devices in sequence (daisy-chaining). USB is
included on all current Macintosh computers.
Most USB audio interfaces support two or four audio channels at one time. USB audio
interfaces vary in quality considerably, so take some time to research them before you
purchase one. The connectors on USB interfaces vary; some interfaces have RCA connectors
and others have both XLR and 1/4" TRS connectors. Very inexpensive USB audio interfaces
may only have a stereo miniplug.
Computer
USB
RCA connector (2)
Analog or digital VTR
Audio interface
Make sure you don’t exceed the total bandwidth of the USB bus. USB 1.1 has a fairly low
data rate, so be careful not to add too many USB items to the bus. Ideally, USB audio
interfaces are always directly connected to your computer, not connected via a hub or
to the computer’s display, keyboard, or another peripheral. If you are having audio
problems with a USB interface connected to a hub, try removing USB devices and
eliminating the hub from the connection.
USB 2.0 audio interfaces are also available. Because USB 2.0 devices can handle high data
rates (similar to FireWire 400), you can treat them similarly to FireWire audio interfaces
(see
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Appendix C
Working with Professional Video and Audio Equipment