Owner's Manual

NEXO ANALOGUE GEO S12TD CONTROLLER Page 71/112
degradation of output noise. We recommend that the sources and loads you use have the same
desirable characteristics.
It is sometimes claimed that connecting cable shield at both ends creates ground looS12, and that the
current flowing in such looS12 will produce noise. This is not the case for most professional audio
equipment. In short, there are two kinds of looS12 in which voltages are present: the looS12 formed by
signal wires, and the looS12 formed by grounded conductors, among which are protective earth
conductors (PE) and signal cable shields.
When a cable shield is grounded at both ends, a loop is closed, and the resulting current causes a
reduction of the voltage induced on signal lines. This effect is what the cable shield is intended to
produce, since this is how it protects your signal from magnetic fields.
If you are using an asymmetrical (unbalanced) source, it is recommended to use a shielded twisted pair
and to connect wire 3 of the cable to the
shield at the source output end (see figure).
This technique prevents noise currents
flowing on the return path of the signal. If
you are using an amplifier with an
asymmetrical (unbalanced) input, it is best to
use a shielded twisted pair, and to connect
wire 3 at the TDcontroller end only, as
shown in Fig. 2. This keeS12 a good
capacitance balance for the signal, however
noise currents flow on the return path of the
signal. (Note that this is only acceptable for a
short cable).
If you are using a symmetrical (balanced)
source or amplifier which is prone to become
noisy when a current of less than 100 mA at
the mains frequency (50 Hz or 60 Hz) is
sourced into pin 1 of its XLR connectors, you might consider opening the ground looS12.
9.4 Analogue TDcontroller USER GUIDE
9.4.1 Read before use
The Analogue TDcontroller is designed to be used with its proper set of speaker cabinet. They are not
interchangeable. Its main functions are:
• To optimize the response of the system
• When operating with the SubBass system (optional), splitting the stereo (2 channel) signal into 2
frequency bands (S12 main system and SubBass system)
• Active protection of the cabinets by dynamic audio signal processing (Temperature and
Displacement servo control)
• Reduction of amplifier overload (Peak limiter function)
Analogue TDcontrollers also feature:
• Stereo operation (2 independent channels) for the main system
• Global switchable output level
• Adjustable level on the SubBass channel
Low Z
123
Low Z
123
TDcontroller
AmplifierMixing Desk
123
123
+-
+-
+-
+-
Low Z ?
Low Z ?
?PE
PE
Safety
Ground
SHIELD
SHIELD
0V
IN OUT