Getting Started
At first, many people can be intimidated by mixing desks. They see a bewildering array of buttons and assume that it is way beyond their understanding.
However, it doesn’t take long to understand the basics of using a simple mixing desk and these basics can be transferred onto more advanced desks.
The most important lesson is to use and trust your ears. This is the most sensitive and powerful instrument at your disposal. Listen to what you are hearing and work out what you are trying to achieve. Just because you have buttons and faders attached to every musician doesn’t mean you have to use them all!

Connecting the desk
All microphones and DI’s are connected to the individual low-impedance Mic inputs of each mixer channel. If CD players, computers or keyboards are connected directly, they should be connected to the line inputs.
DI boxes take a line level signal (e.g. from a guitar pickup or keyboard) and convert it, using a transformer, to a balanced mic signal. This makes it less susceptible to interference, especially on long cable runs.

Knoborama
Every mixing desk is split into two sections channel strips and the master section. At its simplest, the channel strips deal with the sound coming into the desk and the master section deals with the sound leaving the desk.
We have included a selection of channel strips from some of the desks we have in our hire stock here. You might find it useful to print this out to have with you as you view this document.
Different desks will lay out their buttons in different ways, colour them differently and have different additional features but there are many broad areas of the desk that will remain the same.

Input Gain
The gain knob is used to adjust the input signal to an appropriate level as it enters the desk. The usual method for this is to “solo” the channel (press the solo or PFL button, usually near the main fader) and adjust the gain until the signal averages just below 0dB on the meters.

Inserts
Inserts are used to put a processor (such as a compressor or gate) into the signal path. Depending on the desk, this can be either before or after the gain.

Phantom Power
Phantom power is used by active DI boxes and condenser mics. 48V dc is sent down the ‘hot’ and ‘cold’ cores of the mic cable.
Some desks have a button that switches phantom on all channels or none, other desks can switch phantom on individual channels.

EQ
Similar in concept to the tone controls on a stereo. EQ (short for equalisation) is used to change the acoustic characterisation of a source. You can boost or cut a desired frequency to improve the overall sound of a source and hence the mix as a whole.
Some desks have EQ dials in pairs, with one dial controlling the desired frequency to adjust and its partner controlling the degree of adjustment.
Some desks also have a switch to turn the eq adjustments on or off.
While EQ can be used to improve a sound it can not fix everything! It is important to choose the correct microphones for the job at hand, place them correctly and help the users to understand proper microphone technique.

Low cut (or High pass)
This is a dedicated button that can filter out very low frequencies from the channel.
These should be used on all channels that do not have a low frequency component to them, for example vocals. There is no point amplifying frequencies below 250Hz which will usually be produced by banging into a mic stand and the like.

Auxiliaries
These are used to provide an alternative mixture of sound from the main output. This can be used for various purposes: foldback speakers - played back to the musicians so they can keep track of themselves and each other; loop systems – sending vocals to a hearing aid loop without the instruments can improve clarity; recording units and various other ideas.
Aux sends can be pre- or post-fader, some are switchable between the two. A pre-fade aux send works independently from the main fader, this is the usual type of aux used for monitors. IE, if you want to turn down a musician in the main mix you don’t want to adjust the mixture they are hearing.

Pan
The pan control determines where the mono signal appears in the stereo mix. You can use this control to ‘move’ the sound from one side to the other.

Fader
This controls the level of a particular channel added to the main mix.

Subgroups
More complex mixers have the ability to group channels together to simplify a large mix. These groups are then mixed together to form the main mix.