OPTIMOD-PC INSTALLATION
2-21
C)
If you wish to edit an existing (or factory) setup, proceed to step 3 below.
D)
When you are finished setting up each card, close the
I/O
M
IXER
window by
clicking
D
ONE
.
3.
Configure global audio processing parameters.
A)
From the
T
OOLS
menu, open the I/O Mixer and click the Configuration tab
The Configuration page appears:
B)
Set the
M
AX
L
OWPASS
F
ILTER
cutoff frequency.
[10.0 kHz] to [20.0 kHz]
You can set OPTIMOD-PC’s audio bandwidth in two places:
(1) in
C
ONFIGURATION
,
and (2) in the
B
ASIC
M
ODIFY
screen. OPTIMOD-PC’s
bandwidth is always the
lowest
of these settings. The frequency in Setup
is a technical parameter that determines the
highest
bandwidth avail-
able. The installing engineer should set it to be appropriate for the sam-
ple rate of the digital system that OPTIMOD-PC is driving. For example, if
OPTIMOD-PC is driving a system with a 32 kHz sample rate, set the
M
AX
L
OWPASS
F
ILTER
cutoff frequency to 15.0 kHz. That way, a setting of 20
kHz elsewhere will not cause excessive bandwidth and aliasing because
OPTIMOD-PC will automatically override it with the
M
AX
L
OWPASS
F
ILTER
cutoff frequency setting.
Note that the LP filter on the Basic Control page is part of the active pre-
Figure 2-6: Configuration Page in the I/O Mixer
