Waterfall Audio RS700, Instructions Manual

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• The speakers and enclosures of the "Pro Custom Series" range are designed to operate
recessed with the facias flush with the wall. Installation in any other manner will result in a
significant decrease in performance at low frequencies.
• Waterfall custom installation speakers (excluding subwoofers), have a specific horizontal
and vertical mounting requirement for dispersion. It is imperative to adhere to the speaker
product manuals regarding the location of the speakers in relation to the listening area.
• Low frequencies are non-directional, but this does not mean that the sound pressure of
bass will be equal at all points in the room. The location subwoofers relative to the listening
area must be chosen wisely in order to obtain the optimal sound pressure.
Finally, the acoustic qualities of the room plays a predominant role in the final result. Conducting a
proper acoustic study and implementing the findings into the design, using appropriate materials and
acoustic solutions, will play a pivotal part in the overall success of the project.
B. Equalization / Audio Correction:
The acoustic response of a room is characterized by resonance (modes) and cancellations (nulls). This
phenomenon is particularly prevalent at low frequencies. Put simply, the resonances vary in level but
relatively little in frequency, it is therefore quite possible to reduce the intensity of these modes by
electronic correction to improve the sound balance. On the other hand, the nulls are often high in
amplitude (-8dB to -20 dB), and are due to cancellations (caused by phase opposition in a given point
between the wave arriving from the original sound source and a sound reflected by a wall). In addition,
depending on the measurement and listening position the frequencies at which these cancellations
occur will vary. As the null is the result of the positive and negative of the exact same waveform
interacting, the amplitude of the wave does not matter as it will always cancel itself. Even if it were
possible to add an infinite amount of power the result would still equal a null. It is therefore not possible
to correct these by use of DSP. Only the acoustic treatment of the room and the positioning of the
speakers can reduce these cancellations.
For correction / equalization, the best practice is to attenuate the identified modes (and, if necessary,
raise the level in a partial band (shelving) or in the subwoofer band as part of a cinema or stereo 2.1 or
2.2 system.
Any attempt to "boost" the nulls results in a sound imbalance outside the measurement
points and unnecessary overdriving of the amplification and loudspeakers (resulting in a reduction in
dynamic range and an increase in distortion). Some processors define the maximum level of positive
(boost) and negative (attenuation) equalization within in a given bandwidth.
When using in <<SUB>> mode, we recommend limiting any positive equalization boost to between 0 and
+3dB max on the 30-120Hz band (and no equalization boost to frequencies under 30Hz). Once the
equalization is done (mode attenuation), if necessary, you can slightly raise the gain of the LFE channel
to obtain the desired audio balance. Thanks to the precise knowledge of the speakers and their load,
X-TEND™ processing makes it possible to extend the response in the sub bass while reducing the
group delay. With this technology, the speakers are able to work much more efficiently and powerfully.
When this processing is implemented,
we recommend that you avoid any positive equalization boost
so as not to reduce the dynamic range or distort the time optimization that X-TEND™ has produced.
C. Latency Information :
The RS700 circuitry is equipped with high-performance digital signal processing (DSP). Regardless of
the mode used, including digitally chaining multiple devices, this DSP induces a total latency of 1.95 ms.
In the context of a home theatre system, the use of several RS700s (for SUB and speakers) ensures
homogeneous signal processing of the different surround/subwoofer channels. When implementing as
a system with other manufacturers amplifiers (with or without internal digital processing), it is imperative
to adjust the "delays" in the processor so that all amplifiers in the system work to the same basic timing.
Additionally the latency between a speaker and a subwoofer can induce a change in response and a loss
of energy in the crossover frequency band. In stereo use the amplified outputs and XLR outputs of the
RS700 are perfectly synchronous. When XLR outputs are used, it is preferable to use an amplifier without
any internal digital processing so as not to induce relative latency between the two devices.