Sirus Live M416, Руководство пользователя

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Use the Pink noise generator to check the signal routing and loudspeaker response. ‘Pink noise’ is a
random signal that contains all audio frequencies and is therefore a very good test source. Unlike with
‘white noise’ which has an equal energy per HZ and sounds like system or inter-band tuner hiss, pink
noise has equal energy per octave, a response that matches the logarithmic way our ears perceive
sound. You can hear all frequencies clearly from deep bass, through mid to treble. This means you
can route the noise to a speaker system and quickly hear if one tone of the sub, mid or HF drivers is
faulty. With the noise sent to several speakers at the same time you can listen for comb filtering
effects, and the severe phasing effect which indicates that one of the speakers may have its wires
reversed. Pink noise is also used with an RTA (real time analyzer) when measuring room frequency
response. Testing a system with pink noise through the speakers is often referred to as ‘pinking the
room’.
The mixing console signal generator is an invaluable tool for calibrating and testing the system during
setup. To prevent any unexpected mishaps during the sound check or show, remember to disable it by
releasing the recessed ON switch once you have finished the testing. We also advise that you always
start the calibration with the OSC/NOISE trim turned fully off so that you can bring up gradually without
the risk of overloading the destination.
11.3. Mixing with faders or gain controls?
There is a technique used by some operators where they set al the faders to ‘0‘ position and balance
the mix using the channel gain controls. We do not advise this method as the signal to noise ratio and
control resolution can be severely degraded. In addition, it is impossible to mix monitors from FOH in
this way as changes to the gain settings affect the monitors too.
The correct method is to use the GAIN to match the source to the operating level of the channel for
optimum dynamic range, and then use the FADERS to balance each source into the mix. With correct
system gain structure, prime sources such as vocals would have their faders operated around ‘0’ while
sources low in the mix such as backing vocals and acoustically loud brass drums would display their
true contribution with their lower fader positions. This is a much more visual and accurate way of
mixing.
11.4. Using PFL/AFL
We are renowned for bringing you the most comprehensive engineer’s monitoring system in consoles
at this price point. We recognize the importance of correct gain structure and signal handing. The
mixing console includes LED meters for every input channel and main output, as well as a pair of high
resolution meters dedicated to monitor duty only. In monitor mode the M fader and associated controls
become a full featured PFL/AFL monitor feed for the engineers listen wedge.