Mixers
A mixer will take multiple inputs, allow the soundman to set the volume (and other
levels) of each input individually, and then send the "mixed" output to e.g. a set of
speakers for a live audience. There are many variations to the designs; usually the
most notable difference from this one is the presence of faders instead of knobs for
the "gain" on each channel. Obviously, many more than eight channels can be present.
Notice that in addition to gain (volume), each channel can be adjusted for built-in
reverb or some special effects (that can be added using ports in the Master section).
Each channel also has individual controls for high and low EQ. Below the gain knobs are
the inputs, with 1/4" ports for instrument cables and XLR ports for microphone cables.
The 1/4" port on channel 2 has been marked off limits, because it has bit the dirt.
The above is a powered mixer, meaning that it has a built-in amplifier. The mixer shown
below is unpowered, so though it can provide a balance between its four channels, the
output must be sent to an external amp on its way to the speakers. The output from this
one can be sent to the one above, expanding the 8-channel mix into an 11-channel mix.
A couple of possible uses for the 4-channel mixer are (1) controlling the microphone levels of a
vocal quartet and (2) using four microphone to capture various components of a drum set. Added
to the 8-channel mixer, such a setup still leaves seven channels for the rest of an ensemble.
~ FURTHER READING ~
The two most disappointing concerts I have attended, although by two different pop groups, have
this in common: On their recordings, one of the best features (in my opinion) is the close vocal
harmonies; however, in the live performance, the vocals were drowned out by the lead guitar and
various other aspects of the sound. . . . In short, I disagreed with whatever crew operated the . . .