User manual

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through the speaker now. Turning the “Volume” control clockwise or anticlockwise will
increase or decrease the volume level. Subsequent presses of the “Volume” control will
turn the speaker on and off. When switching back on the speaker will go to the last stored
setting when switched off.
Pressing the filter control knob switches the DSP noise cancelling filter on and off, the red
LED indicates filter off, and the green LED filter on (in filter scrolling mode). The filter level
can be changed when in the scrolling mode by turning the filter level control clockwise or
anticlockwise, and a beep will be heard for each filter level step, rising or falling in
frequency depending on whether the filter level is increasing or decreasing respectively.
To store the desired filter level press the filter select control for approximately one second
until a beep is heard and the LED changes to orange. Subsequent presses will turn the
stored filter level on and off. The LED will be orange if the filter is on when in the stored
filter level mode, and red when off. To exit the stored filter level mode, press and hold the
filter control knob for approximately 1 second and the DSP filter will exit back to the filter
scrolling mode.
Note: If the power is on and the DSP is switched off (red LED), the audio passes through
the DSP filter, but without any signal processing.
6. Speaker Tone Level Adjustment
There are four volume level settings for the audible speaker tones; off, low, medium and
high. To change the tone volume level to your preferred setting, press and hold the
volume control until you hear an audible tone and the LED flashes continuously. Release
the volume control to select the current level, otherwise press and hold the volume knob
again until you hear the next tone. (Note that with the audio tone in position off, only the
LED will flash when the volume control is pressed).
7. Sleep Mode
The DESKTOP speaker has a built in sleep mode feature whereby it will be put into
standby mode when there is no signal present after approx 60 minutes. This is indicated
by falling tones. In this mode the speaker only draws a small amount of current (approx
10mA). The speaker will be woken up if a signal is received whilst in sleep mode. This is
indicated by rising tones. If the speaker is switched off manually by pressing the volume
control knob momentarily with power still applied, the sleep mode is inactive and to wake
the speaker up in this instance, press the volume control knob again and the speaker will
switch on, with the last known settings restored.
The sleep mode function can be turned off and on by pressing and holding the filter level
control knob for approx 4 seconds. Falling tones indicate that the sleep mode is enabled,
and rising tones indicate that the sleep mode is disabled.
8. Input Overload
The DESKTOP has audio input overload protection for both the line level and speaker
level inputs. If the signal peaks go over the limits set out in the specification, the LED will
change red and flash 3 times. If the audio level is constantly above the overload
threshold, the red LED will flash continuously. Reducing the audio input level will bring the
speaker back in to normal operation.