Waterfall Audio RS700, Instructions Manual

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IMPORTANT NOTES:
In "SPEAKER" mode, the W1.0 program is designed for Cinema applications where the speakers are
configured high pass (usually at 80Hz) by the Audio-Video processor, X-GUARD™ processing is not
operational. By listening at high power in "pure stereo" mode or if the speakers have been configured to
“WIDE” mode in a Cinema installation, then there will be increased risk of mechanical damage of the
loudspeakers.
• U-GUARD™ PROCESSING
U-GUARD™ processing aims to reduce the formation of square audio signals ( also known as clipping
distortion) at the output of the device when the maximum volume level is reached. The DSP
continuously measures the amplitude of audio signals and limits them so as to never let the power stages
crest to a square signal. The analog circuits are used to create what is known as "soft clipping" to provide
protection from a square signal, which in turn alters the original signal.
The U-GUARD™ processing goes further by maintaining the form of the “clipped” signal closer to the
original which is more natural to listen to. This technology also helps protect power stages and speakers
in extreme cases. This processing is also applied on low-level outputs to avoid overdriving of the XLR
outputs.
• T-GUARD™ PROCESSING
When listening at very high sound levels over an extended period of time, the moving coils within the
Loudspeakers will get hot (this may exceed 200°C) and may lead to a loss in performance of the speakers
or subwoofers. This decrease in efficiency is also known as "thermal compression". Correspondingly with
the power stages of the amplifier being driven hard to achieve high sound levels, the overall operating
temperature of the electronics will be increased.
The T-GUARD™ processing manages, in real time, the thermal parameters of the power stages and also
those of the moving coils in the speakers or subwoofers connected (according to the chosen setup.) It
can help mitigate issues when the devices and/or speakers are being used inappropriately.
The DSP continuously analyses and measures the audio signals transmitted to the power stages and
calculates the average power during a rolling period (from 3 to 12 sec). When the thresholds are
exceeded, the algorithm triggers a drop of -15 dB on all outputs of the RS700 (speaker outputs, XLR
outputs, and digital S/PDIF link) in order to reduce the power level of the system. Depending on the
nature of the audio signals and if the input levels are not reduced, the thermal protection can remain
continuously active. With a drop in the input audio level (about 10 dB), normal operation will resume after
about 25 seconds.
When this protection is active, the 2 red LEDs (13) will be permanently lit . At the same time, the levels on
the power outputs, XLR outputs as well as on the digital output are reduced by 15 dB in order for this
audible alert to be propagated to the equipment connected downstream of the amplifier.
The sudden and general drop in the noise level combined with the permanent lighting of the red LEDs
is a prompt to the user to lower the volume.
NOTE 1 : This processing does not protect the system against errors of installation, handling and use
such as (but not limited to): Improper connection – handling of cables (modulation, networks ...) - switches
at full level - feedback - ground loop - inappropriate signal measurement - short circuits etc.
NOTE 2 : Short-circuit protection is operated directly on the amplifier power stages. It intervenes in case of a
short circuit on the output connections but also in some cases of damage to the speakers and filters. It
generally results in quick cut outs with a degradation of the signal depending on the sound level. If this
occurs, the amplifier should be turned off immediately. Wiring and enclosures must be thoroughly inspected
before recommissioning. If in doubt, consult your dealer and/or authorized service agent.