Threshold / Adjusting The Background Audio Level - Minelab Excalibur II Instruction Manual

Threshold
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Adjusting the Background
Audio Level
Threshold is the constant audible background audio
tone or 'hum' produced by the detector.
The level of the Threshold should be set low/to a
minimum, but still audible and stable. Ideally it should
be a smooth, gentle hum.
Small targets or large deep targets may not produce
a distinct target signal, but may cause only a small
variation in the threshold.
If the Threshold level is set too high or too low, these
very small variations may be missed.
Listening for a target signal with a high threshold would
be like trying to hear a whisper within a crowded noisy
room. A high threshold level may also be uncomfortable
for your hearing.
If the Threshold is set too low, the target signal needs to
be loud enough to become audible, therefore very soft
target signals from small or very deep targets may not
be heard.
It is important to reset the Threshold level as conditions
change. For example, your ears may adjust to the low
levels of audio after an hour or so, or the conditions may
have become windy.
Turn the Threshold control clockwise to increase
the threshold level, or anti-clockwise to decrease the
threshold level.
When the threshold is
too high, a faint signal is
threshold level
masked, and only the peak
of the loud signal is audible
Audio Range that
above the Threshold.
you are able to hear
With the threshold set
correctly, both target
signals are easily heard.
Audio Range that
you are able to hear
threshold level
A threshold level that is too
low does not allow faint
target signals to be heard.
Audio Range that
you are able to hear
threshold level
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