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Owner’s Manual
Owner’
s Manual
Appendix D: FireWire
System Requirements
These are the minimum requirements for your com-
puter system to use the U.420 FireWire interface.
For the PC:
• Windows XP (service pack 2)
• Pentium 4 or Athlon XP processor
• 256 MB RAM
For the Mac:
• OS X (10.3.9 or higher)
• G4 processor
• 256 MB RAM
The internal FireWire interface will allow the left and
right main mix to be recorded on a Mac or PC computer.
It also allows two channels of audio to be added to the
main mix from the computer.
FireWire stream from computer
The following table shows the outputs from your com-
puter to the mixer’s FireWire interface:
The 2-channel digital stream from the computer
enters the mixer through the FireWire connector and is
converted to analog audio.
The audio level can be adjusted using the FW in
control [20].
Beware of a possible feedback loop, if you are
feeding the main mix back into the mixer.
FireWire stream to computer
In addition to a mix of channels 1 to 4, the FireWire
output to the computer can contain any FireWire input
from your computer, if the FW loop out switch [21] is
down.
The mains and phones outputs are not af-
fected by the switch, and always provide a
full mix of channels 1 to 4 and the 2-channel
FireWire input.
The analog audio from the mixer is converted to digi-
tal signals by the FireWire interface’s A/D converters.
The following table shows the outputs to your com-
puter from the FireWire interface:
Here are two examples of using the FW loop out
switch:
Studio Overdub – Tracktion playback is coming
into the mixer on FireWire inputs, and routing
through the mains/phones for you to hear. A
guitar plugged into channel 1 is being recorded
via the FireWire output, while you listen and
play along to the Tracktion playback. The FW
loop switch is up, so the FireWire output to the
computer contains all playing channels except
the FireWire playback.
Live Performance – Computer playback software
like Ableton Live is being mixed to the mains
with other stereo sources such as synths, sam-
plers, turntables, and CD-DJ players. The FW
loop switch is down, so everything will be fed to
the FireWire out for recording an entire set.
To
From
Computer input 1 Left mix of channels 1 to 4
with FW input (switch down)
or without FW in (switch up)
Computer input 2 Right mix of channels 1 to 4
with FW input (switch down)
or without FW in (switch up)
From
To
Computer output 1 Main mix L
Computer output 2 Main mix R
O
O
MAX
LEVEL
U
O
O
MAX
U
O
O
MAX
LEVEL
U
O
O
MAX
U
1
2
FireWire input from computer
3
4
MAX
FW IN
O
O
LOOP
OUT
PRESS IN TO MAKE THIS CONNECTION
FireWire recording channels 1–4 and FireWire in
FireWire recording channels 1–4 only
O
O
MAX
LEVEL
U
O
O
MAX
U
O
O
MAX
LEVEL
U
O
O
MAX
U
1
2
3
4