Nexo NXAMP4X1, User Manual

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MENU DESCRIPTION
If external pilot tone is used (from the audio program sent to the NXAMP on its analog or
digital inputs), be sure that the frequency selected here is as close as possible to the
frequency of the pilot tone.
(2) Internal HF burst generator level
The level of the internal HF burst generator can be adjusted here.
If the load monitoring function is not needed, or if external pilot tone is used, set the level
to OFF.
If the user wants to use the internal HF burst generator for impedance monitoring, then set
the level to the desired voltage between 0.5 and 5 volts. This voltage is intended at the
output of the NXAMP speakon connectors for the channel selected in zone 6, when all
settings are set to default position, with a FLAT setup, except the volume set to 0 dB
attenuation. The true output voltage can be slightly different depending on selected
speaker setup and user settings, but this does not affect the performance of the load
monitoring system.
Set the level to 1 volt is a good start, then adjust the output level to have a stable reading
of the impedance in the zone 7 of the display. Long speaker cable and high impedance
speaker(s) connected might need a higher output voltage. A too big output voltage can
lead to sub harmonic generation that can be audible at the speaker output.
(3) and (4) Impedance low and high limits
Once the measured impedance is display in the Zone 7, you can select low and high limits
that will trigger the fault report on the GPIO port of the NXAMP of on the Ethersound™
network.
To report the impedance fault on the GPIO port, set the GPIO to mode 5 (see above). To
report the impedance fault on the Ethersound™ network, dedicated hardware (like Auvitran
AVNF49-ES) or software should be used. Please contact us for further details on this.
These limits in zone 3 and 4 should be adjusted with care; External parameters such as
cable type and length, temperature, wind and output level can slightly change the
speaker’s impedance measurement.
Be sure to adjust these limits on site in real life conditions to prevent false triggering of the
impedance fault.
(5) Back to previous menu
Use the A button to go back to previous menu (“Options”).
(6) Selected Channel
Use the B button to select the channel currently affected by the settings of the zone 1, 2, 3
and 4.
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