User`s manual

Page 23
they are “out.” Taking one of these filters out and then putting it back in does not
overwrite the programmed cutoff (for the HPF) or maximum gain (for the AGC)
settings.
The two adaptive filters always use their programmed enable/disable setting.
There is no way to enable or disable these filters in standalone mode, so if you
program the unit with one or both of these filters disabled, then it can never be
enabled again until the unit is re-connected to the PC. There is no way to specify
that an adaptive filter should be run in some channel modes but not in others.
nCH Setting Changes
Changes in the nCH setting produce the largest chance of diverging from the
programmed settings. If a reference canceller mode (2CH, 3CH, or 4CH) is
programmed and the unit is changed to another reference canceller mode, then
the behavior is just like a mono/stereo change – the stored settings will be used,
although they will be clamped as necessary to stay within the legal range for the
new channel mode. If a reference canceller mode is programmed and the unit is
changed to a 1CH filter, then the stored settings are no longer meaningful and
are ignored; the 1CH runs at factory default settings. Similarly, if a 1CH is
programmed and the unit is changed to a 2CH, 3CH, or 4CH mode, the 1CH
settings are ignored and factory defaults are used for the reference canceller.
Lock State Changes
When the unit is powered down, its lock state is always preserved in nonvolatile
memory. When the unit is programmed from the PC, it is always programmed to
power up locked. But, if later in standalone mode it is unlocked and powered
down in the unlocked state, then it will power up unlocked the next time.
Similarly, if the unit is powered down locked, it will power up locked the next time
it is turned on.
Preservation of Programmed Settings
Only settings that are controllable from the front panel can be overwritten in
unlocked standalone mode. This means that, if a programmed unit is unlocked
and its front panel settings are changed, then it can be returned to its exact
programmed state by using the front panel controls to return to the original mode
settings.
For instance, say the unit is programmed to use a maximum length mono 2CH
reference canceller. If the unit is unlocked and changed to a stereo mode, then a
ceiling will be applied to the filter size to accommodate the second filter stage
that is required. However, the new clamped filter size is NOT stored in the
nonvolatile memory, so if the mode is later changed back to mono, then the
original programmed size is used.
In short, filter controls available on the front panel WILL overwrite their
nonvolatile memory values once the unit is unlocked. These are: