A sound mixer can also be known as a mixing console or more commonly as an audio mixer. This is an electronic device used for mixing, balancing and combining different sounds and audio signals, sources like microphones, instruments, and synthesizers or previously recorded audio.
The adjusted sound signals are then sent to a result known as the output, which is then transmitted and amplified using a sound system.
The mixer is the central hub where sound signals from different sources are combined and mixed. Effects and ambience can also be added, EQ and stereo imaging are balanced and then the output is directed to the monitor speakers using the mixer.
Some people often become hesitant by the number of channel strips, faders and knobs they see on the mixing desk. In reality most of them are just duplicated with only a few important controls to learn and master. For instance, an audio mixer of a big cinema or concert may have about 100 channels or more whereas a DJ mixer may just have only 2 channels which would be used to mix two signals from the sound source.
There are different types of mixers.
· A digital mixer can both receive digital and more common analogue signals.
· An analogue mixer can receive and process analogue signals.
· A software mixer makes use of digital recording software, which is done via a computer.
The way a mixer works depends on the number of input and output channels it has. For instance, 8×2 mixer means there are 8 inputs channels being mixed into 2 output channel for a stereo recording while a 16×8 mixer means there are 16-in and 8-out options on the mixing console with 16 input channels and 8 output channel for recording a multi-track. With more input channels a mixer has, the more capacity of instruments and sound signals the mixer can combine and blend.
A standard analogue mixer usually has three parts. Understanding how it works will throw more light in learning other types.
The input channels connect the microphones and instruments with the mixer. It consists of:
- Aux (auxiliary): this dictates the amount of effects and reverb each channel has blended. A separate aux also sets the volume of the sound through the monitors and or headphones
- Channel faders: controls the volume of the respective instruments in the mix
- Equalization (EQ) knobs: the tone or timbre of each instrument can be parted into bass, treble or midrange by the EQ knobs. More detailed sound mixers will have more detailed EQ options.
- Bus (sends): Bus channels are used to mainline an effect or processing aspect through the mix. Each instrument track can be fed the bus information in amounts that suit the sound engineer or producer who is working. Using multiple bus options and experimenting with different routing combinations can create different interesting effects for your mix.
- Pan pots: these direct each sound whether instrument or vocal to a particular place in the stereo image field.
The output directs the balanced mix to the track recorder. It is made up of the master channel meters and mixing circuits. The mixing circuit receives signals from the input and blends them together to then send on to the recorder. It also receives return signals from effects such as reverb and delay.
The output section connects also to the monitor amplifier. The meters adjust to the recording volume in order to help you prevent sound distortion.