Pratish Kapoor
The History, evolution and importance of mixing consoles in music.
People have been trying to store sounds on practical and refined mediums for a long time. Édouard-Léon Scott de Martinville was a French book keeper who made the one of Phonoautograph. Scott’s Phonoautograph traced round waves on a carbonised cylinder with a stylus attached to a diaphragm that vibrated from spoken words and does not recorded sound, but data of sound itself.
The era of electricity surged extensive research in magnetism, which allowed the invention of magnetic recording. Thus forth it gave us the ability too infuse multiple simultaneous sound tracks into one storage medium.This was multitrack recording and was invented during the 1930s for testing purposes. It was also made manufactured by German audio engineers during the period of the World War II.
In the early 1950’s Les Paul, along with the companies such as Ampex and Western, facilitated the most crucial advancement that made magnetic tapes become a standard for music consumption and recording around the world.
A Westrex console built for Radio Westrex Portable Stereo Mixer, inside+out
In 1980s, Lots of companies like 3M, Mitsubishi, Sony each starts introducing multitrack digital recorders
Soon Yamaha unveils the ProMix,
the first ‘affordable’ digital
Multitrack console. And since then
there have been multiple
companies who’ve come out with
mixing consoles.
The terms mixer, mixing console, console, board, and desk are often used interchangeably. The main idea is of combining and re-routing audio signals from a set of inputs to a set of outputs with some added signal processing, panning and level adjustment. For the most standard mixers. Almost all mixers and consoles that have microphone or phono inputs include preamplifiers.
Mixers :
Mixers were evolving with companies making small, rack mountable mixers which were one or two rack spaces high around. As shown on the picture, every mixer follows this flow.
Several companies make small, rack mountable mixers that are one or two rack spaces high. These small mixes were usually used for meetings, church prayer or conferences.
Some of them accepted mics, some line input, others a combination. Sometimes limited channel Equalisation was provided, occasionally multi-band EQ and Auxillary bus for effects. But not every mixer had all of the controls. Nowadays The Rack Mount Mixers are also used to increase the capability of the main mixing console.
For ex- ample, if an additional mix of the inputs is needed for a remote feed or a monitor feed, and no more busses are available in the console, the input channels' direct out or insert out jacks can be patched into an external mixer, which are then used to create the additional mixes.
Small mixers are also very popular in broadcast applications, especially remotes. Here, the basic rack mount design may be augmented by a variety of specialised features, including an output level meter, phantom power, a built-in battery and/or DC input for operating the unit, and perhaps even a special output for connection to a telephone line.
Depending on the gig, If the mixer is to contribute to a large sound system, or is to be part of a recording system where the sound goes through the multiple equipment and multiple times.
Then it is advisable to use a Console. Because with only a few mics, if each mic input is a bit noisy (or a bit distorted), the overall effect may not be too bad. Multiply that noise or distortion by 20 or 40 inputs, and then the noise becomes a problem. If the mixer is to stand alone in a small sound system with few performers , less stringent standards may be just fine. Therefore, its necessary not to equate size with quality but rather evaluate according to the gig.
Consoles :
What is a console?
A mixing console is a complex audio system. Not only does it pre-amplify and assign input signals to different outputs, it also allows for a variety of different mixes and special signal routing and processing. The basic path of the signal is as follows: mic or line input to mixing bus to master level control to output. There are generally a number of inputs, of course, with each input being assignable to the busses. Sometimes assignment is via on/off (assigned/not assigned) switches, and sometimes it is via level controls, whereby some portion of the signal is assigned to a given bus.
Pre-Amplifiers is the first active stage unit, it is the first circuit that process the microphone signals, and is connected to a Mixer/Console.
Here the microphones signals are boosted from -70dB to -50dB, which is the nominal output level of microphones. In terms of voltage, the boost is from levels measured in micro-volts (millionths of a volt) to between 1110 volt and 2 volts. The power involved is boosted from tenths of a microwatt (tenths of a millionth of a watt) to between 1;100,000 watt and 211,000 watt.
The console will generally provide equalization, and possibly high pass filters, for each input channel, and sometimes for the output mixes. Other components or functions may be included in the console such as compressors, test oscillators, talkback circuits, and muting logic. Patching facilities are usually part of the console, too, allowing signals to be rerouted so that the signal path inside the console is altered, or so that external equipment can be properly integrated with the mixing system. In short, the console is the heart of the sound system.
Different mixes are used for different purposes. The main output mix in a sound reinforcement console is used to drive the main amplifier loudspeaker system. There may be one or more auxiliary mixes used for driving effects, such as reverb or echo, which, in turn, are mixed back into the main mix. One may want more of some input channels and less of others to contribute to a given effects mix, which is why proportional assignment controls are provided for assignment to the effects bus.
The overall output level applied to any assigned main mixing bus from Input channel is generally adjusted by means of a fader. The main or primary bus is nearly always post- fader. These days, most faders are linear (straight line) controls, rather
than rotary controls. However, smaller mixers, and some larger broadcast consoles, still use rotary faders because they occupy less panel space than linear types, which is sometimes essential in crowded control rooms or remote trucks. On the other hand, some old timers just prefer rotary faders because they grew up with them.
3 types of consoles :
1) True Digital Console : Quickly convert input signals into a digital format and keep them digital throughout the mixing process.
2) True Analog Console : Offers no digital capabilities at all.
3) Analog with Digital : Its internal circuit is in the analogue domain but offers digital audio interfacing at the output stage to allow for direct DAW integration.
Below is the signal flow of an audio through a console. All consoles may not have all these features. As companies are trying to innovate the board with new realises. But most of the industry standard consoles have these functions in them.
Input section :
a.1) Input Gain Control : It sets the Mic or line input amplifier gain to match the level of the incoming signal.
a.2) Phantom power: Many professional Mics require 48V Phantom powering and, sometimes also by switching on the module to turn it on/off.
a.3) MIC/Line Switch: It switches between the channels, MIC input and Line input. The line input could be the playback output from a tape machine. On another line, signal such as synthesiser, guitar or sound effect devices.
b) Routing Section :
b.1) Track Routing Switches : The number of Routing Switches depends on the Console; some will have 24, some 32 & some 48. The switches route the channel path signal to the multitrack machine, and it is possible to route a signal to more than one track.
b.2) Mix Routing Switches : Sometimes there is a facility for routing the channel path output signals to the main display Mix, or to one of perhaps four output groups and these switches will frequently be positioned along with the track routing.
b.4) Odd/Even/Both switch : This switch will determine whether the signal is sent to the odd channel only, the even channel only or both.
b.5) Direct switch: Used for routing the channel output directly in accordance with the corresponding track on the multi-track machine without going via the summing buses. This can reduce the noise level from the console since the summing procedure used for combining a number of channel output to a track bus can add noise of a channel, is routing directly
to a track no other signal can be routed to that track.
C) Dynamic Section :
Advanced consoles include dynamics control over every module.
So that every signal can be handled without resorting to exterior devices. These commonly include compressor and expander sections, which can act as limiters and gates respectively. If required, system allows that EQ to be positioned in the side chain of the dynamic section also, providing frequency sensitive limiting amongst other things. It is usually feasible to link the action of one channel’s dynamics to the next in order to “gang” stereo channel so that the image doesn’t change when one channel has a sudden change in level while the other doesn’t. When dynamics are used on stereo signal it is important that left and right channels have the same setting otherwise the image may be affected
D) Equalizer section :
The EQ section is usually split into three or four sub sections, each operating on a different frequency band and to have similar functions. These will be described in general here.
(a) HF, HMID, LMID, LF
A high frequency band, high Mid, Low Mid and Low frequency band equilizations are often provided. If the mode is parametric, these bands will allow continuous variation of respective frequency ‘Q’ and boost/cut. If not parametric, then there may be few switched frequencies for the Mid frequency band and perhaps a fixed frequency for LF and HF bands.
(c) ‘Q’ :
The ‘Q’ of a filter is defined as its centre frequency divided by its bandwidth (the range between frequencies where the output of the filter is 3db lower than the peak output) in practice this affects “the sharpness” of the filter peak or notch, high ‘Q’ giving the sharpest response and Low Q giving a very broad response.
Low ‘Q’ would be used when Boost/Cut over a relatively wide range of frequencies is required.
While high ‘Q’ is used to Boost/cut one short specific region
(d) Frequency Control :
Sets the centre frequency of peaking filter or the turn over frequency of a shelf
(e) Boost/Cut :
Determines the amount of boost or cut applied to the selected band usually up to maximum around ±15db
(f) HPF/LPF :
Sometimes the high and low pass filters are positioned here instead of at the input. In addition they normally have a constant frequency turnover point and a constant roll-off of either 12 or 18db per octave. These will often function even if the EQ is switched off.
(g) In/Out :
Equalization circuits can introduce noise and phase distortion, so they are best switched off when not required, by input cut off switch.
E) Channel & Mix Controls
Pan :
When a pair of busses is used to carry a stereo signal, it is generally essential to be able to assign a given input to either or both of these busses in an constant proportion. The relative signal level on the left and right busses of the stereo pair will determine the perceived stereo position of the sound image. A pan pot (short for panoramic potentiometer) is nothing more than a pair of specially tapered pots (level controls) wired back-to-back so that as the level going out of one pot increases, the level going out of the other decreases.
In sound system applications, it is desirable to taper the resistance elements in the two sections of the pan pot so that when the pot is centred, the output level from each section is 3 dB less than it would be if the pot were turned all the way up for the individual section.
(c) Line/Tape or Bus/Tape
In Line or Bus mode the monitor paths are effectively ‘Listening to’ the line output of the console’s track assignment buses while in ‘Tape’ mode the monitor paths are listening to the off tape signal.
(d) Bus or Monitor Bus :
It routes the output of the monitor fader to the input of the channel path (channel fader) so that the channel fader will be used as a post-fader effects send to any one of the multi-track buses.
(e) Mute or cut :
There are two types of cut switches one for cutting the channel signal from the multi-track send the other for cutting the Mix signal from the mix.
(f) PFL :
Pre fade listen is the signal monitoring without pass through fader, the signal coming from the source without routing to fader.
(g) AFL/Solo :
After fade listen is similar to PFL this is sometimes called as solo, which routes a panned signal of the track to the main monitor, cutting all other signals, these functions are useful for isolating signals at the time of setting. In most of consoles, the AFL Bus will be stereo. Solo functions are useful when applying EQ and effects, one may hear the isolated sound and treat individually without hearing the rest of Mix.
E) Auxiliary section :
(a) Aux Sends : It controls for the level of each individual channel in the numbered aux mix.
(b) Pre/Post switch : It determines that whether the signal send in taken off before or after the fader. If it is before, then the send will still be live, even when the fader is down, effects sends will normally be taken post fade.
(c) Mix/Channel : Determines whether the send is taken from the Mix or channel paths: it will often be sensible to take the send from the channel path, when effects are to be recorded on to multi-track rather than on to the Mix. This function is labeled ‘WET’
(d) Mute : It will cut the numbered send from the aux mix.
F) Master Controls :
This section normally placed on the right hand end of the Audio Console or now in
the digital Mixers, it is on the middle of the Console. It has following facilities:
a) Monitor Selection : Monitor selection means it will feed the signal to the loud speaker of the control Room/Studio but not the mix output, there are many switches to select the source to be monitored like. Aux sends, the main stereo mix on Tape Machines etc.
b) Dim : It decreases the level of the signal feed to monitor around 40db, for quick silencing of the room.
c) Record/Overdub/Mix Down : This Facility, depends the mode of operation, the Mic/Line input switching, large and small faders and auxiliary sends. This will over write the signal on one another or it will dub the signal on an appropriate position (between memories we have given)
d) Auxiliary Level Control : This is the master control for setting the overall level of each Aux send output.
e) Talkback : Talkback is usually placed on the console, having a small built in Microphone, which is usually used for giving instruction to the studio hands ( instrumentalist ) from the control room and which can be routed to a number of destinations like Aux sends, Mix bus or studio loud speakers etc.,
f) Oscillation : For analog tape recording, we need the magnetic tape to be given bias, which is a signal of frequency of accurate 1khz and 10khz tone. The 10khz tone is the accurate setting the bias of an analog tape machine, in which the tone (1khz, 10khz) is fed to the tape from the Mixers “oscillator” option or sometimes it is given from the Tape Recorder facilities option.
G) Metering Section :
Metering system is placed on audio consoles to measure the level of the audio signal feeding in & coming out from the Mixer. This is important for measuring the audio level without noise & distortion and to record the correct sound.
Usually two types of metering are provided in the audio console.
1. Mechanical Meter
2. Electronic Bar – graph meter.
Mechanical Meter: Generally two types of Mechanical meter have been used.
VU ( volume unit ) Meter
(b) PPM ( Peak Program) Meter
In the VU meter, there is associated variable attenuator, which could vary the electrical alignment level for O VU up to +24dBu. Now it is common for this to be fixed these days at OVU = ±4 dBu
In Electronic bar graph meter there can be an infinitely fast rise time, although this may not be ideal in practice but cheaper bar graphs are made out of new of LEDS (Light Emitting Diode) & the resolution accuracy depends on the number of LEDs used.
There is a facility provided to switch the peak response of these meters from peak to VU mode. where they will imitate the scale and ballistic response of a VU meter.
The main advantage of the Bar graph vertical VU meter is that it takes a little space on the audio mixer.
STEPS OF INSTALLING CONSOLES IN A STUDIO?
Analog condoles, where built of individual modules. Each ,module is a channel, which has not all but most of the different sections discussed above for signal to travel. The manufacturer first designs the base for the mixing desk first and then all the channels are installed on the desk separately.
As seen in the pictures. We can see the process, how the guy in the first picture is painting the desk first. And the second picture the board is ready to be installed modules in it. And all the modules can bee seen in the pictures below
Usually the company first assembles there console test it and then it’s de-assemble all the modules before they are delivered to the customer. Usually a company
engineer comes for the installation. But if the customer has basic understanding of installing the modules, then it can assembled.
Depending on the companies, either the modules have a solid back and can be slid into the desk. But some companies to save money, instead of sliders they use rubber strips which connects into the console.
With the computers getting more and more advanced and DAW(Digital Audio Workstaion) coming into the picture, Digital Console were introduced. They were in a high demand, since there were light and no modules were used to build them, Only faders and knobs which send the data to the computer. Below are 3 console, Euphnic CS3000 which as the first digitally controlled analog console. And Avid System 6 and SSL XLDesk both of which are digital consoles.
Euphonix CS3000
It was one of the first console to build a bridge between the analog and digital world. It was the first Digitally controlled analog console. s
The system foundation consists of four component.
The digital Mix Controller, The Audio Tower, The patchbay, and The support computer.
The Mix Controller : The Mix Controller resembles a conventional control surface in many ways, with rotary controls, faders, and routing displays. However, the Mix Controller is basically a group of computer systems working together, connected to the remotely located Audio Tower via a multi-way serial cable snake. This snake passes information from the Mix Controller to the electronics in the Audio Tower. Every block of 8 faders in the Mix Controller is a computer, as is the Master Controller and the Digital Studio Controller
The Audio Tower : A single Audio Tower can accommodate up to 56 faders worth of audio. Consoles above 56 faders have two Audio Towers; the first houses. The audio electronics for 48 faders, and the second for up to 56
faders, making a potential maximum of 104 faders.
The Support Computer : The Euphonix system includes a high-speed, 19” rack-mounted support computer. The support computer is connected to the Mix Controller via a high speed data link which enables it to manage all of the other computers in the Mix Controller. It drives the screen display and the disk storage facilities as well. During automation the support computer keeps track of all the moves and transfers mix data to and from the Mix Controller. The computer, associ- ated hardware and the MixView software package, is often referred to as the MixView Platform. In the unlikely event of a support computer failure, the Mix Controller and Audio Tower can operate on the fly without it.
The Patch Bay : Systems include high-quality Euphonix patchbays. As a custom option, sys- tems may be supplied without patchbays. This is generally discouraged since Euphonix patchbays are tested with the system to ensure signal integrity throughout the system. The Euphonix patch system has one dual 48-jack row for each group of 8 faders, and one for the Master Audio Module.
AVID SYSTEM 5
Soon, Euphonix was bought by Avid and they used there technology to make the Avid System. Which is considered to be one of the best Digital mixing consoles.
Avid was the first company to take the big leap into digital. With there DAW Pro Tools, Avid system consoles were the best option around that time.
Overview and some features of the System :
The Control Surface connects to the processing core via Ethernet and the EUCON Hub. The Audio does not pass through the control surface.
The SC264 System Computer runs the eMix software application; all file management and system setup is done from that computer.
Expandable DSP SuperCore can accommodate over 450 audio channels, each fully resourced with EQ, dynamics, Aux sends, panning, and routing.
Modular control surface with up to 112 channel strips, each with 8 touch- sensitive encoders and a motorized 100mm fader per channel
Customizable modular I/O to match your needs.
View metering, routing, panning, and EQ/dynamics visual feedback on high-resolution TFT displays
Mix multichannel audio in up to 7.1 surround
Control multiple DAWs with the EUCON Hybrid option.
SSL XLDESK
XL-Desk is a digital twist on the classic analogue studio console. It’s designed for tracking or mixing engineers who require an analogue console within a DAW-centric studio, but don’t want or need the integrated DAW control and analogue level automation.
Features of XLDESK :
20 + 1 fader, over 40 input SuperAnalogueTM SSL console
8-built in Variable Harmonic Drive (VHD) preamps
16 dual input mono channels (switchable between main input or DAW return)
4 stereo channels (switchable to mono for tracking).
The legendary Stereo Bus Compressor, with new high-pass filter sidechain
18-slot 500-series rack built-in, accessible from channels or mix busses
In addition to a 500-series rack insert each mono channel also has a standard insert point
4 stereo Mix Buses with their own insert points and access to the 500 rack.
This is a perfect mixing console for small studios or can be used as the second mixer in the studio.
CONCLUSION :
To conclude, Mixing console are the heart of any studio. Without them one can’t get the High-Quality sounding product. Importance of mixing was released long ago, and people having been striving for the best sounding mixing desk since then. It clearly can be seen that we have come a long way from the days when the First Phonoautograph was made. With the ability of multi track recording, people have been lucky to be able to experience the magic of music and films. With ever evolving technology, Digital consoles have made the Consoles easy to use, much faster and light weighted. Companies Amek, Euphonix, Avid and SSL have also played a huge role in revolutionising the Entertainment Industry. And the reason the audience are able to experience and feel different dimensions within the music and films, Mixing Consoles played a very important role in it.
References :
http://www.soundrecordinghistory.net/history-of-sound-recording/multitrack-recording-history/
http://cemca.org.in/ckfinder/userfiles/files/10_Lesson-09_AUDIO_CONSOLE.pdf
https://bgaudioclub.org/uploads/docs/Yamaha_Sound_Reinforcement_Handbook_2nd_Edition_Gary_Davis_Ralph_Jones.pdf
http://www.aes.org/aeshc/docs/audio.history.timeline.html
https://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwjx8LPxxerTAhXLBcAKHcqhC9UQFggpMAA&url=http%3A%2F%2Fdzwiek.org%2Fattachments%2Fg_series_shortform-pdf.3408%2F&usg=AFQjCNGNzO_q2I3opGvue1XcZ-g1vkqITQ&sig2=iCygtKtiz11LBOCTHuxvrQ
http://sslweb.solidstatelogic.com.s3.amazonaws.com/content/XL-Desk/pdfs/docs/SSL-XL-Desk-Owners-Manual.pdf
https://medias.audiofanzine.com/files/euphonix-cs2000-3000-manual-471935.pdf
http://www.evolutionstudios.co.uk