Fundamentals of Audio Production

1
Fundamentals of Audio Production

• Chapter Five
• Mixing Consoles

2
Three Functions of the Mixing Console

• Amplify
• Mix
• Route or Direct

3
Amplification

• The gain stage is the first stage in the
  console.
• Setting proper gain is critical for clear audio.
• Gain settings too low result in noise
• Gain settings too high result in distortion
• Click to hear distortion from high gain
• Click to hear noise from low gain

4
Gain Setting

• If gain is too low, turning up output levels will
  also increase the level of the inherent noise, as
  in the top illustration.
• Proper gain settings maximize signal to noise
  ratio, as in the bottom illustration.

5
Clipping

• Setting gain too high may result in clipping.
• The signals wave form becomes clipped when it
  exceeds the circuits capacity.
• Clipping causes the wave to become square and
  distorted.

6
Gain Setting

• Many recording and live sound consoles provide
  clip indicators to assist in proper
  gain-setting
• When the peak indicator illuminates, distortion
  will result.

7
Mixing

• Adjusting the relative levels of the audio
  signals leaving the mixer.
• Mixing is accomplished using the consoles faders
  or potentiometers.
• In most consoles, the potentiometers only cut or
  reduce levels.
• Faders full up no cut
• Faders completely down full cut

8
Potentiometers

• Most simple potentiometers use resistance to
  reduce levels.
• As the wiper is moved further from the input, the
  output level is reduced.

9
Mixers
Linear faders
10
Mixers
Rotary Potentiometers
11
Mixing is aided by meters
12
Meters Calibration

• All devices in the recording chain must be
  calibrated to assure proper levels.
• Using a steady tone, the console meter is set to
  100 modulation or 0 VU.
• Then all device inputs are adjusted so their
  meters match.

13
Meters Calibration
When all devices are calibrated, then maintaining
proper meter levels on the console will assure
that other devices are not over-driven.
14
Routing or Directing

• Sending the signal to a variety of destinations.
• Signals are transported via buses.
• Buses are simply wires or paths for the signal to
  travel.

15
Routing or Directing

• Typical console outputs
• Main or stereo bus
• Subgroups
• Monitor or foldback send to headphones
• Effects sends to outboard effects devices
• Auxiliary sends
• Cue sends to headphones or cue speakers
• Different manufacturers use different terms

16
Routing or Directing
Stereo Master Fader
17
Routing or Directing
Subgroup Faders
18
Routing or Directing

• Signals may be routed to outboard devices either
  pre fader or post fader.

19
Routing or Directing

• The pan control routes the signal to the left and
  right stereo channels.

20
The Mixing Console Connections
21
The Mixing Console Connections
22
Mixers
23
Mixers
24
Mixers