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M 18 Digital Mixer User’s Manual
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M 18 Usage
Secrets of mixing on a digital console
The most important thing to keep in mind using a digital console is the Gain Structure.
Mixing is essentially an art, but the Gain Structure is based on mathematical reasoning and represents the
most important thing to learn to manage before taking off with your mixing creativity!
The correct input level, starting from the Analog Gain, with all the further processing inside the mixer, must
be set by checking continuously the master output to avoid overload because digital consoles work
differently from analog ones.
The 0dBFS level (where FS stands for full-scale) refers to sound level in the digital domain, inside the mixer
itself, and corresponds to the maximum signal that can be applied to an Analog-to-Digital conversion stage:
above this level, the conversion process clips the signal and sever distortion appears.
A fair starting point to set the proper Analog Input Gain is to set the individual sounds levels in the range of
-18 .. -14 dBFS.
One of the most powerful but often underestimated tools is the High-Pass Filter (HPF); in the M Series
mixer the HPF is located in the PRE-DYN page. The proper HPF setting on the individual channels is
important to optimize the processing of the audio sources, and furthermore it also helps to cut away some
subsonic inaudible components of the sounds that often cause an efficiency loss of the power amplification
system.
It’s highly suggested to always use the HPF on all the input channels, especially on mic inputs during live
gigs where the HPF is a great tool to reduce the noises captured by the microphones by transmission (as an
example, foot stomping or noises captured touching the mic stands).
How to set the HPF?
Generally, except for instruments with lot of low end like a Kick Drum or Bass, 50Hz is a good frequency to
start with. The HPF is not only the first tool to optimize the signal chain but it must be considered like an
EQ band, and for this reason it should be used to easily optimize the frequency range aimed to achieve a
more focused overall balance between the different sounds
A classic example of HPF usage in frequency range optimization is on the Toms. When played alone, Toms
have huge energy in the low end; in a mix of medium density of instruments the perception of those low
frequencies is masked by other instruments, so to make the Tom sound more focused we could boost some
mid-hi frequency or cut some low end with the HPF – 100Hz and above - and increase the level.
This approach allows to keep the same RMS audio level (matching the perceived audio level), but with an
optimized frequency range.
The approach described for Toms above should be reiterated for all instruments.
Gain Input Level, HPF and Gain Structure are the most important elements to keep in mind for the usage of
a digital console.