Nexo GEO D - Manual (Page 15)

GEO D G ENERAL S ET - UP I NSTRUCTIONS Page 15/97
• Bridge-Mono: the second signal channel processes the same input as the first channel, but with
reversed phase. The (single) load is connected between the two positive channel outputs using a
suitable connection. While the total output of the amplifier remains the same, the available output
voltage, the minimum impedance that can be connected and the voltage gain are doubled as
compared with stereo operation. Typically, only channel 1 input is active. Positive and negative
output connections vary depending on amplifier manufacturers.
NEXO does not recommend Bridge Mono Mode unless amplifier power is clearly not sufficient.
IMPORTANT
When in Bridge-Mono mode, check your amplifier user manual for proper connection of
outputs 1(+) and (2+) in relation to input phase.
• Parallel-mono: the output terminals of the two channels are configured in parallel using an
internal relay. The (single) load is connected either to the output of channel 1 or to that of channel
2 (as if in stereo). While the total output of the amplifier remains the same the output voltage level
is also the same as in stereo mode. The minimum impedance that can be connected is reduced
by half due to the fact that current capability is doubled. Typically, only channel 1 input is active.
NEXO does not recommend Parallel-Mono Mode for any GEO D10 or GEO SUB amplification.
Warning on amplifiers signal processing features
Some high-end amplifiers may include signal processing functions similar to those found in the NX242
TDcontroller ("loudspeaker offset integration", "limiter", "compressor," etc.). Moreover, when this
processing is digital, computation latency time can introduce a few milliseconds delay from input to
output. These functions are not adapted to specific system requirements and may interfere with the
complex protection algorithms used in the NX242.
NEXO do not advise using other protection systems in conjunction with the NX242 and they should be
disabled.
IMPORTANT
For proper system protection, no latency time or non-linear devices should be
introduced between the output of the NX242 TDcontroller and the input of loudspeakers
through use of DSP modules such as internal amplifier signal processing.
2.2.5 Example
For a 6 GEO D10 and 2 GEO SUB cluster, and considering an amplifier model which is capable of
delivering 2 x 3300W into 2 Ohms or 2 x 2300W into 4 Ohms, NEXO recommends the following
quantities and settings:
• GeoD Passive Mode:
2 amplifiers, 3 x GEO D10 per amplifier (1 channel LF rear, 1 channel LF/MF/HF Front), mode
switch in Stereo position, Gain switch in 26 dB gain position, all dynamic or filter processing
switches off.
• GEO SUB :
1 amplifier, 2 x GEO SUB per amplifier (1 channel VLF rear, 1 channel VLF/LF Front), mode
switch in Stereo position, Gain switch in 26 dB gain position, all dynamic or filter processing
switches off.
Which gives a total of 3 identical amplifiers for such a cluster.