You would sometimes wonder why on earth the sound of the live performances of bands seems to be solid even from different vantage points. How do they do it? Well, this is possible because of the use of digital mixers for live sound. Sound engineers always work feverishly behind the scene to ensure that the audio output of live performances are balanced and palatable to the ears of the listeners, and they make this possible via the use of digital mixers for live sound.
To tinker with sound using digital mixers, however, is not an easy task. It requires an in-depth understanding of various factors like the signal flow, room size, compatibility of the digital mixers with your computers and other devices, good ears for mixing vocals and other sounds. It also requires excellent skills in mixing sounds and these skills are never achieved overnight. Other than the audio interface and mic preamps. The digital mixer is also one of the music equipment you must have on your mixing / music console desk. But what is a digital mixer for live sound after all?
Table of Contents
- Understanding Digital Mixers
- Understanding the Intricacies of Mixer Controls
- Recommended Best Live Sound Digital Mixers:
Understanding Digital Mixers
The digital mixer is an electronic device used in sound processing, specifically for combining sounds from different audio sources using digital circuitry. The digital mixer—otherwise known as mixing desk, mixing console or mixing board—is widely used to engineer sound quality in both recordings as well as in live broadcast like in public address (PA) system. It is also used to change the sound dynamics and many other properties of the audio signals using one or more of its multiple input channels. Moreover, with the use of the digital mixer, you can easily tweak or add effects to audio signals; afterward, you can combine these signals to mono or stereo output for amplification on a PA system. This process is called a “house mix.”
When engineering a “house mix” for a particular indoor venue like an auditorium, you should take into consideration the acoustic parameters of the location in order to incorporate the various adjustments needed in volume, equalization, treble, bass, and other effects. House mix can significantly improve the sound quality produced inside an auditorium, especially, during concerts or musical plays. However, you can never use a house mix when recording the audio of such event as its use could significantly diminish the audio quality.
Digital mixers usually have a number of the descriptor that describes their input-output functions. A three-number descriptor like that of the 24:8:2 indicates the number of inputs, output buses, and master output channels, respectively. A two-number descriptor, on the other hand, indicates the absence of output bus. Presonus studiolive, Allen & Heath and Behringer x32 are the some of the most popular and high-end mixers you can easily spotted on the live concert.
Understanding the Intricacies of Mixer Controls
The basic unit of a digital mixer consists of the channel and digital mixers. The appearance of a digital mixer alone can be very intimidating for a novice due to the number of knobs and sliders on its channel console. If you would learn to understand how one channel works, you would surely be able to understand entirely how the digital mixer works because every channel basically has the same functions as the other channels. Once an audio signal enters the input, it travels through the various parts of the mixer down to the slider or fader before being passed through the output. These myriads of parts of the digital mixer include the following:
This is the terminal where an audio source (e.g., microphone, guitar and keyboard) can be connected to the digital mixer. The input terminal usually has an XLR connection port for microphone and a ¼-inch jack for line signal source like a keyboard.
The insert connection allows you to apply additional effects by diverting the audio signal out of the channel into the “effects unit” like those of the limiter, reverb, or compressor, while at the same time, returning the audio submix to the channel instantaneously for scheduled programming. The insert also allows you to divert the audio signal for recording or to another mixer without having the audio signal returning to the mixer. The insert terminal is a ¼-inch three-conductor TRS jack. While the TRS phone jack is typically used for the insert; however, the two-conductor T/S phone jack could also be used. The audio signal may be inadvertently removed from the mix when the jack is pushed all the way.
The gain is the first set of knobs under the insert that is used to control the input level in a channel. The gain allows you to prevent distortion and overloading of the channel.
This control knob allows you to change the sound’s frequency curve just like when the sound source is “bright.” In such a case, you can quickly reduce high frequencies via the EQ. Many mixers feature a 3-band EQ that allows you to raise or diminish the low, mid, and high frequencies separately.
The “auxiliary send” or “aux send” allows you to create “auxiliary” mix and you can also use this for different tasks. You can make use of it to create a monitor or headphone mix to allow performers to hear themselves amid performances or to send an audio signal to the effects unit via aux send output. When using a common effects unit like reverb, it is possible to control all channels using a single effects (FX) unit by connecting the effects unit back to the mixer using the aux return input. If the mixer doesn’t possess this feature, the FX unit should be connected back to one of the mixer’s channel inputs.
The aux send is also used for sending audio signal from a certain channel for recording. This feature is especially helpful when doing overdubs. The aux send can also be used to create a submix. There are two ways to use the aux send; either you can use by Pre-fader or by Post-fader. In Pre-fader mode, the aux level can only be controlled from the “aux send” knob, and can’t be affected by the channel fader. In post-fader mode, the opposite happens, and the aux level can only be controlled from the channel fader.
Pan or Panorama
The Pan is used to control the stereo field where the sound will be heard. When you turn the pan control knob to the left, the audio signal is boosted to left output and vice versa. In a multi-bus mixer, you can rout an audio signal to a particular output bus by merely pressing a button on individual channels. Each button corresponds to two outputs (e.g., 1 and 2, 3 and 4, etc.) When you want to direct to bus #1, you can turn the pan control all the way to the left. To direct it to bus #2, you can turn the pan control all the way to the right. In panning, it is essential to keep the vocals, bass guitar, kick and snare drums in the middle.
Mute control allows you to stop the channel from sending a signal to any output. In case that the mixer mute has “solo” button, this button allows you to mute everything except the “soloed” channel or channels.
The channel fader controls the level of audio signal that is being passed to the bus or master output. The channel fader is also used to control the sound “mix” that goes to PA system or to a recording device.
This is the overall audio level control before the audio is being sent to the bus or master output.
This is where the “mixed” audio signal departs the digital mixer for amplification. The master output usually has a pair of XLR terminals as well as ¼-inch jacks for left and right outputs and headphone jack.
Recommended Best Live Sound Digital Mixers:
1) Mackie DL1608 16-Channel Live Sound Digital Mixer
This model features a powerful 16-channel digital live mixer that provides seamless wired to wireless mixing. It also provides the sound engineer complete control from his iPad via the use of its highly intuitive Mackie Master Fader app. Many sound engineers worldwide have attested to the proven reliability of this digital mixer. It has been used in millions of gigs worldwide and has proven to be impeccable in providing awesome live sound mixes. It is convenient and portable and provides impressive ease-of-use using an iPad.
It is ideal for use in band production and other types of audio productions. It provides awesome mobile freedom to its users and allows for wireless control of the mix and powerful plug-in processing of audio anywhere within the venue. Lastly, its hardware with its 16 high-quality Onyx preamps and its Cirrus Logic converters would surely deliver sterling and unparalleled sound quality to the listeners.
2) Mackie DL DL806 8-Channel Digital Live Sound Mixer with Apple Lightning Connector
Mackie DL DL806 8-Channel Digital Sound Mixer with Apple Lightning Connector is an awesome 8-Onyx mic preamp that combines an awesome power of reliable digital mixer that you can easily use using your iPhone connector. It provides its users unmatched freedom to wirelessly operate and control the mix anywhere within the given venue. It features 8-channel DL806 hardware with its eight boutique-quality preamps together with Cirrus Logic converters that are capable of producing unparalleled audio quality. It also features an intuitive Master Fader app for iPad Model and includes an Apple Lightning connector.
3) Fosa Mixing Console Mini 3-Channel Sound Card Mixing Console
Fosa Mixing Console Mini 3-Channel Sound Card Mixing Console is a stereo digital mixing console that is equipped with XLR and LINE switchable outputs. It features a 3-channel insert point with capability of processing additional effects. It also features a one AUX auxiliary main line output. Fosa Mixing Console Mini 3-Channel Sound Card Mixing Console comes with built-in digital delay effect for creating a superb super cool mixing sound effect. It also features a built-in MP3 music player with USB port, support U disk input for playing your favorite songs. This digital mixing console is surely widely used in many small stages, Bars, and KTV box, and is surely dependable in creating an awesome music ambiance.