Signal Flow & Audio Consoles MSD2013 – SOUND DESIGN I

Prepared by: Mr. Ajoi

Signal Flow

Why…??

Knowing the audio path through a mixing console is absolutely critical to a sound engineer’s success.

Using this information, the engineer can quickly TROUBLESHOOT the likely causes of common problems, and can even narrow down the possibilities of unexpected major problems.

Basic Signal Flow

Pre-Amplifier

Consoles

Power Amplifier

DAW (PC)

Analog Console Signal Flow

Mixer vs. Console

Mixer vs. Console

The terms mixer, mixing console, console, board, and desk are often used interchangeably.

All are used for combining and re-routing audio signals from a set of inputs to a set of outputs, usually with some added signal processing, and level adjustment.

Mixer vs. Console

Console is an abbreviation for mixing console.

Mixer generally refers to a small unit, either rack mountable or with fewer than 10 to 12 input channels.

The differences between them are that a mixer is small, quite portable, and performs limited processing functions.

The console is larger, substantially so in many models, more complex, and perform numerous processing functions.

Portable Microphone Mixer

Analog Consoles

Console: Mackie CFX16 MkII

Analog Consoles The basic path of an audio signal is as follows: •mic or line input to mixing bus to master level control to

output.

Mic or Line Input

Mixing Bus / Channel Strip

Master Level Control

Output

Analog Console Signal Flow

Channel Strip

The Channel Strip Sections Inputs

Inserts

Auxiliary/Effects Sends

Equalizations

Pan pots

Channel Assignments

Channel Faders

Inputs Section Microphone-line input selector

• controls which signal source enters the input section.

Phantom power • Just ahead of the microphone preamplifier is the phantom power supply ( 48 volts

DC). • When activated it provides voltage for condenser mics, thus eliminating the need for

batteries.

Trim/Gain Knob • The trim is a gain control that controls the nominal input levels of various input sources.

Pad • reduces the power of a signal. It is used when the trim, by itself, cannot prevent

overload in the mic signal.

Inputs Section

Inserts Section High-end production consoles usually include a inserts/dynamics section after each I/0 module for added signal processing.

It often includes compression, limiting, and noise gating.

Auxiliary Sends Section

The aux (auxiliary) send control (also called

effects [EFX or FX} send, reverb send, or echo send) feeds the input signal to an external

(outboard) signal processor, such as a reverberation unit,

compressor, or harmonizer.

Equalizations section An equalizer is an electronic device that alters a signal's frequency response by boosting or attenuating the level of selected portions of the audio spectrum.

Most production consoles have separate equalizer controls for selected frequencies grouped in the lo, middle, and high ranges.

Pan Pots Section

pan pot (short for panoramic potentiometer) is a control that can shift the proportion sound to any point from left to right between two output buses and, hence, between the two loudspeakers necessary for reproducing a stereo image.

Channel Assignment / Buss Sections

This is a group of switches on each

channel strip used to direct the signal from

that channel to one or more outputs; or

several input signals can be combined and

sent to one output.

Solo & Mute Switches Solo

• This is a group of switches on each I/O channel used to direct the signal from that channel to one or more outputs; or several input signals can be combined and sent to one output.

Mute

• The mute function, also called channel on/off, turns off the signals from the I/O channel.

Channel Faders The channel and

monitor faders control the channel level of the signal being recorded and its monitor level,

respectively.

During recording channel levels to the

multitrack recorder are set for optimal signalto-

noise ratio.

Other Sections • master buses, master fader, aux (or

effects) send, aux (or effects) return, and meters.

Master section includes:

• Speakers volume, recorder select, send, mix, loudspeaker select, and mono switches.

Monitor section includes:

• talkback, slate/talkback, and oscillator.

Communications section includes:

Video Mixing Console Explain (Part II):

http://www.youtube.com/watch?v=_11Z3BEUArY

Digital consoles

Digital Consoles Digital consoles use the assignable concept in

three configurations:

• in an analog console that is digitally controlled

• in an all-digital console • in a virtual console which is not a console per

se, but an integrated system that combines a harddisk computer and specialized software to record and process audio direct to disk.

Digital Consoles

With digital consoles, instead of individual controls for channel-to-track routing on each channel strip, these functions have been centralized into single sets so they can be assigned to any channel.

Digital Console: Mackie d8b

Digital Consoles Signal Flow

Video Sound One Studios:

http://vimeo.com/19688642

References

Alten, Stanley R.. Audio in media. 6th ed. Belmont, Calif.: Wadsworth Pub. Co., 2002. Print.

Davis, Gary D., and Ralph Jones. The sound reinforcement handbook. 2nd ed. Milwaukee: Hal Leonard, 1989. Print.

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