Making the Most Of Your Mixer
MG10/2
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The First Steps in Achieving Great Sound
Before you even consider EQ and effects, or even the overall mix, it is important to make sure that levels are
properly set for each individual source. This can’t be stressed enough—initial level setup is vitally important for
achieving optimum performance from your mixer! Here’s why … and how.
3-1. The Head Amplifier “Gain” Control Is the Key!
Let’s review our simplified mixer block diagram:
Each and every “stage” in the mixer’s signal path will add a certain amount of noise to the signal: the
head amp, the EQ stage, the summing amplifier, and the other buffer and gain stages that exist in the
actual mixer circuit (this applies to analog mixers in particular). The thing to keep in mind is that the
amount of noise added by each stage is usually not dependent to any significant degree on the level of
the audio signal passing through the circuit. This means that the bigger the desired signal, the smaller the
added noise will be in relation to it. In tech-speak this gives us a better “signal-to-noise ratio”—often
abbreviated as “S/N ratio.” All of this leads to the following basic rule:
In our mixer, that means the head amplifier. If you don’t get the signal up to the desired level at the head
amplifier stage, you will need to apply more gain at later stages, which will only amplify the noise con-
tributed by the preceding stages. Just remember that too much initial gain is bad too, because it will over-
load our channel circuitry and cause clipping.
To achieve the best overall system S/N ratio, amplify the input to the desired average
level as early as possible in the signal path.
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MG10_E.book Page 11 Monday, May 26, 2003 1:52 PM
