user manual
NuQ series
LMS-D24/D26 Audio Connections
Audio Input connectors
These are fully balanced and are wired pin 1 ground, pin 2 hot and pin 3 cold. The two inputs have pin 1 connected directly to the chassis and feed the signal processing chains. If an unbalanced source is used, a connection should be made between the pin 3 ‘cold’ signal and the ground connection of the unbalanced source.
Audio Output connectors
The processed outputs are impedance balanced, and are wired pin 1 ground, pin 2 hot and pin 3 cold. An unbalanced input may be driven by connecting pin 3 ‘cold’ signal to the ground connection of the unbalanced destination input. Note that output pins 1 are ground lifted at audio frequencies but connected to ground at RF for good EMC performance. The intention being that the amplifiers the processor is driving should be responsible for the grounding of their input cable shields.
Presets and Secure mode
A momentary button is fitted on the rear panel, between the output XLRs and the RS232 port. When activated, this will disable all the front panel controls so they cannot affect the signal path, making the unit secure against tampering. When in secure mode, the indicators still operate normally however; Presets cannot be stored or recalled. If the unit is not responding then check that Secure Mode is not active.
Note that the communications port is still active in secure mode.
NuQ manual page 31