Cadac CDC four User Manual

CDC FOUR

Digital Mixing Console

User Manual

Cadac Holdings Ltd.
One New Street
Luton
Bedfordshire
LU1 5DX

Telephone: [phone]
Fax: [phone]

Email:
General information: [e-mail]
Service enquiries: [e-mail]

IMPORTANT SAFETY INFORMATION

CAUTION: These servicing instructions are for use by qualied personnel
only. To reduce the risk of electric shock, do not perform any servicing
other than that contained in the User Manual unless you are qualied to do
so. Refer all servicing to qualied service personnel.

1. Read these instructions.

2. Keep these instructions.

3. Heed all warnings.

4. Follow all instructions.

5. Do not use this apparatus near water. Do not expose this apparatus to dripping

or splashing and ensure that no objects lled with liquids, such as vases, are

placed on this apparatus.

6. Clean only with a dry cloth.

7. Do not block any of the ventilation openings. Install in accordance with the
manufacturer’s instructions.

8. Do not install near any heat sources such as radiators, heat registers, stoves,

or other apparatus that produce heat.

9. Only use attachments/accessories specied by the manufacturer.

10. Refer all servicing to qualied service personnel. Servicing is required when
the apparatus has been damaged in any way, such as the power-supply cord or
plug is damaged, liquid has been spilled or objects have fallen into the apparatus,
the apparatus has been exposed to rain or moisture, does not operate normally,

or has been dropped.

11. To completely disconnect mains power from this apparatus, the power supply

cord must be unplugged.

3

For US and CANADA only:

Do not defeat the safety purpose of the grounding-type plug. A grounding-type
plug has two blades and a third grounding prong. The wide blade or the third

prong is provided for your safety. When the provided plug does not t into your
outlet, consult an electrician for replacement of the obsolete outlet.

The lightning ash with arrowhead symbol, within an equilateral triangle is

intended to alert the user to the presence of an uninsulated “dangerous voltage”

within the product’s enclosure that may be of sufcient magnitude to constitute a

risk of electric shock to persons.

The exclamation point within an equilateral triangle is intended to alert the user to
the presence of important operating and maintenance (servicing) instructions in
the literature accompanying the appliance.

Revision 1 2012-13CDC FOUR

4

GENERAL PRECAUTIONS

• Do not place heavy objects on the control surface, expose it to sharp objects
or handle the console in any way that may cause damage, e.g., rough

handling and/or excessive vibration.

• Do not subject the equipment to dirt, dust, heat or vibration during operation

or storage. Never expose the console to rain or moisture in any form. Should

the console become wet, turn it off and disconnect it from the mains without
further delay. The console should be given sufcient time to dry out before

recommencing operation.

• When cleaning the console, never use chemicals, abrasive substances or

solvents.

• The console control panel should be cleaned using a soft brush and a dry
lint-free cloth. For persistent marks, use a soft cloth and isopropyl alcohol.

Switches and potentiometers do NOT require cleaning or lubrication. For

faders, see below.

• Keep these instructions for future reference. Follow all warnings in this

manual and those printed on the console.

• The console must be connected following the guidance in this manual. Never
connect power amplier outputs directly to the console. Connectors and

plugs must never be used for any other purpose than that for which they are
intended.

• The console mains input must always be connected to correctly rated mains
power as referred to in this manual. The mains input must, at all times, be

connected to the local mains power supply using the supplied power cord.

In cases where the supplied plug does not t, a qualied electrician must be

consulted.

• The power cord must be routed in such a way that the risks of accidentally
stepping on it, stretching it or it being pinched are minimized.

• WARNING ! THIS EQUIPMENT MUST BE EARTHED !

• Ventilation slots must never be covered or obstructed in any way, otherwise
airow required for safe operation may be restricted. Where the console is to
be operated in its ight-case, then this must be located in such a way that it

allows for proper ventilation.

• Refer servicing to qualied technical personnel only.

Revision 1 2012-13 CDC FOUR

CONFORMITIES

Declaration of Conformity

The Directives covered by this declaration: 2004/108/EC

The Products Covered by this Declaration: CDC FOUR audio mixing consoles

The Basis on which Conformity is being Declared: The products identied above

comply with the requirements of the above EU Directive(s) by meeting the
following standards:

BS EN 55103-1:2009 Product family standard for: audio, video, audio-

visual and entertainment lighting control apparatus for professional use.
Part 1 – Emission.

BS EN 55103-2:2009 Product family standard for: audio, video, audio-

visual and entertainment lighting control apparatus for professional use.
Part 2 – Immunity.

5

BS EN 61000-3 -2:2008 Electromagnetic Compatibility (EMC) Part 3.
Limits. Section 2. Limits for harmonic current emissions (equipment input

current ≤16 A per phase).

BS EN 61000-3 -3:2006 + A2:2009 Electromagnetic Compatibility (EMC)

Part 3. Limits. Section 3. Limitation of voltage uctuations and icker in low
voltage supply systems for equipment with rated current ≤16 A.

BS EN 60065:2002 + A1:2006 Audio, Video and similar electronic apparatus.

Safety requirements.

BS EN 61000-4-2:2009 Electrostatic discharge immunity test.

BS EN 61000-4-6:2009 Immunity to conducted disturbances.

BS EN 61000-4-11:2004 Immunity to voltage dips, short interruptions and

voltage variations

Attention!

The attention of the specier, purchaser, installer, or user is drawn to

special measures and limitations to use which must be observed when
these products are taken into service to maintain compliance with the
above directives. Details of these special measures and limitations to use

are available on request, and are also contained in this User Manual.

Revision 1 2012-13CDC FOUR

6

Contents

IMPORTANT SAFETY INFORMATION 3

For US and CANADA only: 3
GENERAL PRECAUTIONS 4
CONFORMITIES 5
Declaration of Conformity 5

Introduction 8

What’s in the Box 8
Overview 8
CDC FOUR – Main Feature Set 9
Stagebox options 10
Mechanical details 11
Power supply matters 12

Controls and Connections 13

Top view - control surface 13
Rear view – connector panel 14
Connector details 15

Block Diagram 18

Fundamentals 19

Central Assignment Module 19
Layers 23
Screen displays - overview 25
Screen navigation 29
Softkeys 30

Audio channel descriptions 31

Input channel 31
Stereo inputs 38
Groups 39
VCA groups 41
Aux outputs 43
Stereo master 45
FX sends and returns 49

Other screen pages 51

Channel 51
Routing 51
Metering 53
EQ detail 54
Dynamics detail 54
FX processing 58
System 62
Scene Control 67

Revision 1 2012-13 CDC FOUR

Other mixer functions 70

Graphic Equaliser 70
USB port 71
Ethernet port 71
MIDI 71
User buttons (U1 – U4) 72

Technical Specication 73

Appendix 74

Input Channel Block Diagram 74
Stereo Inputs block diagram 75
Groups block diagram 76
Aux outputs block diagram 77
Stereo master block diagram 78
Phones/Monitor block diagram 79
Maintenance page 80
Connecting the CDC FOUR to unbalanced sources and
destinations 82

7

Revision 1 2012-13CDC FOUR

8

Introduction

What’s in the Box

The CDC FOUR console is shipped in a triwall carton. Before unpacking, inspect

that the carton has not been damaged during shipping. If there are any signs of

damage, inform the shipping agent.

Inside the carton, you should nd the following items. If any are missing, contact
your Cadac distributor immediately.

• CDC FOUR mixing console

• IEC power cable (with UK/European or US connector as appropriate)

• Detachable gooseneck console lamp

• This manual

Overview

Thank you for purchasing this Cadac CDC FOUR digital audio mixing console.

From its founding in 1967, Cadac’s products have indisputably become the
benchmark for sound reinforcement consoles. The CDC FOUR is Cadac’s rst
compact digital mixer and is an all new development, based on a proprietary DSP

mix platform. It makes available many of the features of our world-famous large-

scale theatre and touring analogue desks in a compact, portable and fully-digital
package. However, you will still nd the attention to detail, high quality audio

circuitry and reliability on which the reputation of the Cadac brand is built.

The CDC FOUR’s basic conguration is 32/4/2, with 16 mic/line mono channels

and 8 stereo channels. It also has 8 aux sends and 8 VCA groups. Input channels
can be increased for live work with the optional CDC RACK Stagebox giving up
to a further 32 inputs.

Ergonomically, the CDC FOUR employs the now-familiar concept of “layering”
to reduce the width of the mixer to less than 19”, having 16 motorised plus one

manual (stereo master) 100 mm faders. The control surface has been designed
to be as familiar as possible to operators mainly used to working with analogue

Revision 1 2012-13 CDC FOUR

consoles. All the functions of the single, assignable, largely-standard channel strip
are duplicated on the high-resolution TFT colour display, allowing the engineer to

use either “conventional” controls or operate the mixer mainly through the display.

The CDC FOUR has a rear panel expansion port which can be tted with a

dedicated CADAC multichannel digital interface for use with the optional CDC
RACK stagebox.

CDC FOUR – Main Feature Set

• 16 mic/line inputs

• 8 stereo inputs

• 4 group outputs plus stereo main output

• 8 VCA groups

• 8 aux sends

• 2 internal FX processors

• 4-band parametric EQ on all channels and groups

• Variable-frequency HPF on all channels

• Dynamics section (compressor/limiter plus gate) on all channels

• Adjustable per-channel delay

• Inserts and Direct Outs on all channels

• Fully-featured Monitor, PFL and Talkback sections

• Internal Universal PSU

• 7” 800 x 480 pixel TFT display

• Scene automation, with 100 mm motorised faders

• 96 kHz, 24-bit Delta-Sigma AD and DA convertors

• Fourth generation 32/40-bit oating-point SHARC processors

• Low-noise, wide dynamic-range analogue mic pre-amps with gain controls

• Channel functions controllable either from standard channel strip or via

display

• Dedicated hardware bargraph meters on each input and stereo main output

• Global metering display

• Dynamics gain reduction displays

• Optional interface card for the CDC RACK expansion stagebox

• Optional remote stageboxes (32-in/16-out or 32-in/8-out) with proprietary

interface

• Optional rackmount kit

• Gooseneck console lamp

• No fans – silent in operation

9

Revision 1 2012-13CDC FOUR

10

Stagebox options

The CDC FOUR is designed to integrate immediately with existing analogue live

sound installations, and may be used stand-alone, with a conventional stagebox

and snake.

If more than 16 mic/line channels are required, a CDC-RACK can be added. This
is a remote stagebox with integral, remotely-controllable analogue mic pre-amps

of the same high-quality design as those in the CDC FOUR. It uses a proprietary

multichannel digital protocol developed by CADAC to connect to the mixer, and

two coaxial cables replace a conventional snake.

The CDC-RACK is a 19” rack-mounting unit which can be tted with either 16
inputs and 8 outputs, or 32 inputs and 16 outputs. The additional input channels

are available to the user using control surface layers (see ”Layers” on page

23). In the case of the 8-output version, the stagebox output connectors can

be assigned to any eight of the CDC FOUR’s various outputs.

Revision 1 2012-13 CDC FOUR

180.8

9.2

11

Mechanical details

436.0

569.6

85.5

520.0

NOTE: when installing the CDC FOUR in a permanent or semi-permanent

situation, an additional allowance must be made at the rear of the console for

connectors and cables.

Fitting the rack mounting kit

The CDC FOUR is supplied with a pair of rack mounting brackets which permit
the mixer to be installed in a standard 19” equipment rack.

To install the brackets, remove the three upper screws (those closest to the mixer

control surface) which secure each metal end cheek to the chassis. Fit the rack

mounting brackets over the end cheeks and ret the three screws. Note that
the brackets are handed (i.e., one is designed to t on the left hand side of the
console and the other to the right). This is indicated by an ‘L’ or ‘R’ label afxed

to the bracket.

Revision 1 2012-13CDC FOUR

12

Power supply matters

The CDC FOUR has an internal Power Supply Unit (PSU). The AC mains power

switch is located on the rear panel, integral with the IEC receptacle to which AC

mains is connected.

Removing the IEC cable from the rear receptacle will electrically isolate the CDC
FOUR from the AC mains supply.

It is always good operating practice to turn a mixer on BEFORE turning on the

ampliers, etc., to which its outputs are connected. Similarly, always turn the
ampliers off BEFORE turning the mixer OFF.

An IEC cable is supplied with the mixer to connect this to the AC mains supply.

The cable should be tted with a mains plug suitable for your country; if this is not
the case, either obtain one of the appropriate type, or replace the tted plug with

one of the correct type. Note the supply mains cable colour coding is as follows:

Mains connection Mains cable core colour

Live Brown

Neutral Blue

Earth (Ground) Green/Yellow

The PSU in the CDC FOUR is a “Universal” type, and may be connected to any

AC mains supply voltage of between 90 and 260 V, and frequency 50 or 60 Hz.

The IEC receptacle is integrated with both the mixer’s power on/off switch and a
mains fuseholder (immediately above the connector). If it is necessary to replace

this fuse, please only do so with one of the same type and rating:

115 or 230 V AC

Fuse type T2LA, 20 mm dia. anti-surge

Fuse Rating 2 A

Note that the integral fuseholder has storage space for a spare fuse.

This fuse is the only user-replaceable component the CDC FOUR contains. A

mains fuse should never be replaced without rst making an attempt to ascertain
the reason for its failure. If you are unsure why the fuse failed, or if the replacement
fuse also fails immediately, consult your Cadac dealer.

Revision 1 2012-13 CDC FOUR

Controls and Connections

Top view - control surface

13

MIC 1MIC 2 MIC 3MIC 4 MIC 5MIC 6 MIC 7MIC 8 MIC 9MIC 10MIC 11MIC 12MIC 13MIC 14MIC 15MIC 16

60 0600 60 0600 60 0600 60 0600 60 0600 60 0600 60 0600 60 0600 60 0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

3

3

3

3

3

3

3

3

3

3

3

3

3

6

6

6

6

6

6

6

6

6

6

6

SOLO

MUTE

VCA 3
AUX 7

6

9

9

12

12

15

15

18

18

24

24

36

36

54

54

SEL

SEL

SOLO

MUTE

10

10

+

+

5

5

0

0

5

5

10

10

0

0

20

20

30

30

40

40

50

50

60

60

-

-

∞

∞

VCA 4
AUX 8

9

9

9

9

9

9

9

9

9

12

12

12

12

12

12

12

CHNS
17 - 32

SOLO

MUTE

ST RT 2

AUX 3

12

15

15

18

18

24

24

36

36

54

54

CHNS

DEL RCL SVE COPY PASTE

33 - 48

PN

SEL

SEL

SOLO

MUTE

+

10

+

10

5

5

0

0

5

5

10

0

10

0

20

20

30

30

40

40

50

50

60

60

-

-

∞

∞

TAPE RT

AUX 4

15

15

15

15

15

18

18

18

24

24

36

36

54

CENTRAL ASSIGNMENT MODULE CENTRAL CONTROL MODULE STEREO MASTER OUTPUT MODULE

+

TRIM

+

HPF

GATE

+

THR

COMP

+

THR

20:11:1

RAT

+

LVL

LIM

+

THR

DLY

SmS

BYP PST

+

0

-

54

HI LO

-

48V

FREQ

+

-

REV

dB

HF

WN

HPF

Q

HI LO

FREQ

+

dB

HMF

-

WN

IN

Q

HI LO

-

FREQ

+

IN

dB

LMF

WN

AUT

-

Q

VIN

HI LO

-

FREQ

IN

+

dB dB

LF

WN

IN

Q

SEL

SEL

SOLO

SOLO

MUTE

MUTE

+

10

+

10

5

5

0

0

5

5

0

10

0

10

20

20

30

30

40

40

50

50

60

60

-

-

∞

∞

ST 1

ST 2

GP 1

GP 2

18

24

24

36

36

54

54

AUX 1

FX 1

0

0

ON

∞

IN

-

PRE

AUX 2

FX 2

0

0

ON

∞

PRE

AUX 3

IN

0

ON

∞

-

PRE

AUX 4

0

ON

∞

PRE

IN

AUX 5

0

ON

∞

-

IN

-

EQ
IN

SEL

SOLO

MUTE

ST 3
GP 3

LRGR

PRE

AUX 6

0

ON

∞

PRE

AUX 7

0

ON

∞

PAN

PRE

AUX 8

0

ON

∞

PRE

SEL

SOLO

MUTE

10

+

10

5

5

0

0

5

5

10

0

10

20

20

30

30

40

40

50

50

60

60

-

∞

∞

ST 4
GP 4

18

24

36

54

ON

∞

PRE

ON

∞

PRE

0

0

3

3

6

6

9

9

12

12

15

15

18

18

21

24

GT

36

LIM

54

12

3

4

LR

LR

LAYER SELECTCONTROL

IN

SOLO

MUTE

SEL

SEL

SOLO

SOLO

MUTE

MUTE

+

10

+

5

0

5

0

10

0

20

30

40

50
60

-

-

∞

ST 5

ST RT 1

AUX 1

AUX 2

15

18

24

36

54

USB

METERS

SCENE

FX

ROUTE

SYSTEM

CHN

CHNS
1 - 16

ST

OUTPUTS

CHNS
VCA

+

10

5

0

5

0

10

20

30

40

50
60

-

∞

9

12

12

15

15

18

18

24

24

36

36

54

54

SEL

SEL

SOLO

SOLO

MUTE

MUTE

CH 9CH 1 CH 2 CH 3 CH 4 CH 5 CH 6 CH 7 CH 8 CH 10 CH11 CH 12 CH 13 CH 14 CH 15 CH 16 MASTER

CH 25CH 17 CH 18 CH 19 CH 20 CH 21 CH 22 CH 23 CH 24 CH 26 CH27 CH 28 CH 29 CH 30 CH 31 CH 32

CH 41CH 33 CH 34 CH 35 CH 36 CH 37 CH 38 CH 39 CH 40 CH 42 CH43 CH 44 CH 45 CH 46 CH 47 CH 48

10

10

+

+

5

5

0

0

5

5

10

10

0

0

20

20

30

30

40

40

50

50

60

60

-

-

∞

∞

VCA 1

VCA 2

AUX 5

AUX 6

6

9

12

15

18

24

36

54

SOLO LOGIC

ENTERCLEAR

SEL

SOLO

MUTE

10

5

0

5

10

20

30

40

50
60

∞

VCA 5

FX 1

+

HOLD SIP

SEL

SOLO

MUTE

+

0

-

VCA 6

FX 2

12

15

18

24

36

54

TALK

ADJUST

3

6

9

U1

U2

U3

U4

-

10

+

5

0

5

10

0

20

30

40

50

60

-

∞

3

6

9

12

15

18

24

36

54

0

3

6

9

12

15

18

24

36

54

LRGR

COMP

-

+

THR

20:1 1:1

RAT

-

+

LVL

LIM

-

+

THR

BYP

GRAPHIC EQ

1-16

BANDS

17-32

SEL

SOLO

MUTE

10

+

5

0

5

10

0

20

30

40

50
60

-

∞

VCA 7 VCA 8

0

3

6

9

12

15

18

24

36

54

0

3

6

9

12

15

18

21

GT

LIM

IN

AUT

VIN

IN

PST

6/12

IN

SEL

SOLO

MUTE MUTE

FREQ

HF

Q

FREQ

HMF

Q

FREQ

LMF

Q

FREQ

LF

Q

10

5

0

5

10

20

30

40

50
60

∞

+

MONITOR

+

SUM M

HI LO

WN

HI LO

WN

HI LO

WN

HI LO

WN

TALK
BACK

PHONES

dB

dB

dB

SOLO

-

M

-

IN

-

+

IN

-

+

IN

-

+

IN

-

+

EQ
IN

10

5

0

5

10

20

30

40

50
60

∞

Mic pre-amp gain controls

Per-input bargraphs

Central Assignment Module – “channel strip”

Channel faders with SEL, MUTE and SOLO

Stereo fader with MUTE and SOLO

Central Control Module, including TFT screen and primary display controls

Layer selection controls

Screen navigation controls

System utility controls, PTT button and parameter “soft knob”

Stereo output channel

Solo logic controls

Talkback and monitor controls

Graphic equaliser controls

Revision 1 2012-13CDC FOUR

14

Rear view – connector panel

7 101156

LITTLITES

LEFTRIGHT

MONO

MON M

GP4

AUX 4

AUX 8

TALKBACK

GP3 GP2 GP1

AUX 3AUX 2AUX 1

AUX 7

AUX 6

MON LMON R

TAPE L OUTTAPE R OUT

CH 15

INSDO

AUX 5

INSDO

ST R8 ST L7ST R7 ST L6ST R6 ST L5ST R5 ST L4ST R4 ST L3ST R3 ST L2ST R2 ST L1ST R1

CH 13 CH 11 CH 9 CH 7 CH 5 CH 3CH 1

INSDO

INSDO

ST L8

INSDO

INSDO

INSDO

INSDO

IN OUT

MIDI

THRU

INSDO

INSDO

INSDO

INSDO

812 13 1415 9

* shown without optional CDC RACK interface installed

No. Connection Qty. Marking

1 Mic/line inputs 16 CH 1-16

2 Stereo line inputs 16 ST 1-8

3 Channel direct outputs (one only indicated) 16 DO

INSDO

INSDO

ETHERNET

INSDO

CH 2CH 4CH 6CH 8CH 10CH 12CH 14CH 16

INSDO

1

3

2

4

4 Channel insert send/returns (only one indicated) 16 INS

5 Group outputs 4 GP 1-4

6 Aux send outputs 8 AUX 1-8

7 Stereo master outputs: L, R and mono sum 3 LEFT, RIGHT, MONO

8 Stereo tape outputs 2 TAPE OUT, L & R

9 Monitor outputs: L, R and mono sum 3 MON L, R, M

10 Talkback mic input 1 TALKBACK

11 DC output for console lamp 1 LAMP 12V

12 Expansion port* 1 -

MIDI ports 3 MIDI IN, THRU, OUT

13

14 Ethernet network port 1 ETHERNET

15

IEC mains connector, fuse and AC power switch 1 -

* shown without optional CDC RACK interface installed

Revision 1 2012-13 CDC FOUR

Connector details

This section provides electrical details of the CDC FOUR’s inputs and outputs.

The tables at the end of this section, referred to in each connector description,

summarise wiring details.

1. Mic/line inputs 1-16 - Neutrik® Combo A connectors. These sockets accept

either a 3-pin XLR male connector or a ¼” (6.35 mm) 3-pole (TRS) jack plug. The

sensitivity of the XLR input is suitable for microphones, while the jack input, which
has an 18 dB pad, is intended for line level sources. The inputs are electronically

balanced with an impedance of 1.2k ohms (mic) or 10k ohms (line). Nominal input

level at the XLR (with gain control at minimum) is 0 dBu; maximum input level
is +21 dBu. (Note that Cadac dene 0 dBFS to be equivalent to +21 dBu in the
CDC FOUR). 48 V phantom power is available at the XLR pins of this connector,

switchable from the channel strip.

The mic/line inputs should be wired as per Table A (XLR connectors) or as per
Table B (jack plugs).

15

2. Stereo line inputs 1-8 – eight pairs of ¼” (6.35 mm) 3-pole (TRS) jack sockets

(separate L and R inputs). Intended for connection to the line outputs of external

stereo equipment, including outboard FX processors and stereo tape returns.

The inputs are electronically balanced with an impedance of 10k ohms. Nominal

input level is 0 dBu; maximum input level is +21 dBu.

The stereo line inputs should be wired as per Table B.

3. Direct outputs 1-16 – pre-fade outputs from each of the 16 mono mic/line

channels. The outputs are electronically balanced on ¼” (6.35 mm) 3-pole (TRS)

jack sockets, and have a maximum output level of +21 dBu.

The direct outs should be wired as per Table B.

4. Channel inserts 1-16 – send and return insert points in each mono mic/line

channel. The send and return are both unbalanced, and have a maximum level of

+10 dBu. The connectors are ¼” (6.35 mm) 3-pole (TRS) jack sockets.

The inserts should be wired as per Table C.

5. Group outputs 1-4 – post-fade outputs of the four audio subgroups. Outputs

are electronically balanced on ¼” (6.35 mm) 3-pole (TRS) jack sockets, and have

a maximum output level of +21 dBu.

The group outputs should be wired as per Table B.

6. Aux sends 1-8 – the outputs of the mixer’s eight auxiliary busses. Every

channel can send pre- or post-fade to each Aux buss, and each Aux buss has a

master level. The Aux busses can be used as sends to external FX equipment

(normally pre-fade), or as performers’ foldback (normally post-fade). The outputs
are electronically balanced on ¼” (6.35 mm) 3-pole (TRS) jack sockets, and have

a maximum output level of +21 dBu.

The Aux sends should be wired as per Table B.

Revision 1 2012-13CDC FOUR

16

7. Master outputs – the main outputs of the mixer. Three XLR male connectors

are provided: for left and right channels, and a mono sum of left and right
(L+R) - 6dB. The outputs are electronically balanced, and have a maximum

output level of +21 dBu.

The master outputs should be wired as per Table A.

8. Tape outputs – a secondary, buffered set of master outputs on ¼” (6.35 mm)

3-pole (TRS) jack sockets, intended to facilitate connection of a stereo recording

device. The signals at the L/R Tape Out connectors are identical to those at the

L/R Master Outputs [7] above, and are post the master fader and mute. There
is no equivalent mono sum output. The outputs are electronically balanced, and

have a maximum output level of +21 dBu.

The Tape outputs should be wired as per Table B.

9. Monitor outputs - the mixer’s monitor outputs. Three ¼” (6.35 mm) 3-pole

(TRS) jack sockets provide stereo monitoring, or a mono sum of left and right.
The stereo outputs are useful in a recording situation, but the same signal is

available for use in live sound at a dedicated headphone output under the front

armrest, with a separate level control. The mono sum output can also be used

in live sound situations to feed an engineer’s local wedge monitor. The monitor

source may be selected to be the master outputs, the PFL/AFL system or the
stereo tape return. The rear panel outputs are electronically balanced, and have

a maximum output level of +21 dBu.

The monitor outputs should be wired as per Table B.

10. Talkback mic – a 3-pin female XLR connector on the rear panel for a

dedicated dynamic mic or connection to a comms system.

The talkback mic should be wired as per Table A.

11. Console lamp – a 3-pin female XLR for connection of a gooseneck lamp to

provide console illumination.

12. Expansion port – this may be tted with an interface card for the CDC RACK

expansion stagebox; this uses a dedicated CADAC digital multichannel protcol.

13. MIDI ports – standard MIDI In, Out and Thru connectors

14. Ethernet port – RJ45 connector for software updates

15. AC mains - see “Power supply matters” on page 12 for wiring details.

Revision 1 2012-13 CDC FOUR

Table A*

Pin Connection

1 Screen

2 Signal ‘hot’ (phase)

3 Signal ‘cold’ (antiphase)

Table B*

Pin Connection

Tip Signal ‘hot’ (phase)

Ring Signal ‘cold’ (antiphase)

Sleeve Screen

Table C

17

Pin Connection

Tip Send

Ring Return

Sleeve Screen (common)

* See the Appendix for information about connecting the CDC-FOUR to unbalanced sources and
destinations.

Revision 1 2012-13CDC FOUR

18

Block Diagram

STEREO LR

AUX 1-8

FX 1&2

GROUP 1-4

AFL LR

PFL

Aux Output (TRS)

Group Output (TRS)

Monitor Output Left (TRS)

Headphone Output (TRS)

Monitor Output Right (TRS)

Monitor Output Mono (TRS)

Monitor Outputs

Stereo Output Right (XLR)

Mono Output (XLR)

Stereo Output Left (XLR)

Tape Output Left (TRS)

Tape Output Right (TRS)

Stereo Outputs

Internal mix busses

CDC FOUR - Basic Block Diagram

Mono Inputs 1-16 Aux Outputs 1-8

Mono Input (XLR)

Direct Output (TRS)

Insert Send/Return (TRS)

Stereo Inputs 1-8 Group Outputs 1-4

Stereo Input Left (TRS)

Stereo Input Right (TRS)

Internal FX Returns 1 & 2

FX Returns 1 & 2 (Internal)

Revision 1 2012-13 CDC FOUR

Fundamentals

Although the CDC FOUR control surface and operating system has been

designed to retain the familiarity and facilities of an analogue console, there are a

number of important aspects of its operation which differ markedly from analogue
mixers. These include the following concepts:

• Assignability - a single channel strip whose controls can be assigned to any
of the internal signal channels;

• Layers – the faders can be switched to control another set of channels or
groups, resulting in a small control surface for a large conguration mixer;

• TFT screen – most of the mixer’s controls and statuses are accessible
through the built-in display as well as by using hardware controls; some mixer
functions are only available via the screen;

• Soft keys – various controls whose functions vary depending on the current
state of the display, or of other mixer settings.

Central Assignment Module

19

CENTRAL ASSIGNMENT MODULE

-

+

48V

TRIM

-

REV

+

HPF

HPF

GATE

-

+

THR

COMP

-

+

THR

20:11:1

AUT

RAT

-

+

VIN

LVL

LIM

-

+

THR

DLY

SmS

BYP PST

HI LO

FREQ

HF

WN

Q

HI LO

FREQ

HMF

WN

IN

Q

HI LO

FREQ

IN

LMF

WN

Q

HI LO

FREQ

IN

LF

WN

IN

Q

AUX 1

0

IN

-

+

dB

AUX 2

0

AUX 3

IN

0

-

+

dB

AUX 4

0

IN

AUX 5

0

-

+

dB

AUX 6

0

IN

AUX 7

0

-

+

dB

AUX 8

0

EQ

IN

FX 1

0

ON

∞

PRE

∞

PRE

∞

PRE

∞

PRE

∞

PRE

∞

PRE

∞

PRE

∞

PRE

FX 2

0

ON

0

ON

3

6

9

12

ON

15

18

24

36

ON

54

LRGR

12

3

ON

LR

LR

ON

PAN

ON

∞

PRE

∞

PRE

SOLO

MUTE

The Central Assignment Module (CAM) is essentially a single,

ON

fully-featured channel strip, such as would be found on an

analogue mixer. The obvious differences are that potentiometers

ON

are replaced by continuous (360°) rotary encoders, and the push-

buttons are electronically latching and internally illuminated. The

0

encoders have a “press” function; turning the encoder knob while

3

pressing it in allows a ner degree of parameter adjustment. The

6

9

use of rotary encoders means that the value of the parameter

12

15

which the control varies is not related to the physical position

18

21

of the knob – in fact, the knobs do not have a pointer of any

GT

LIM

kind. Another implication of this system is that all the channel
parameters have default values which have nothing to do with

4

knob positions; these values can be regarded collectively as the

“initial state” of the channel. The actual value of each parameter

is available from the TFT display; this topic is covered in greater

IN

detail under “Screen displays”, see page 25.

The CAM controls the mixer’s DSP section, and is used to set the

channel parameters for the following mixer sections:

• All mono mic/line channels

• Stereo inputs 1-8

• Subgroups 1-4

• Aux. sends 1-8

• FX returns 1 and 2Note that unlike an analogue mixer, many of the channel

facilities found on an input channel strip are available to the output sections

of the CDC FOUR. Furthermore, there is no signicant difference in the

facilities available to stereo line input channels compared to mono mic/line
input channels.

However, it should be noted that not every channel facility is available to all types
of signal channel. The exceptions are noted in a later section of the manual, see

“Audio channel descriptions” on page 31.

Revision 1 2012-13CDC FOUR

20

SEL

SOLO

MUTE

CH 1
CH 17
CH 33

+

-

+

TRIM

-

+

HPF

GATE

-

+

THR

COMP

-

+

THR

20:11:1

RAT

-

+

LVL

LIM

-

+

THR

DLY

SmS

BYP PST

The SEL button

Each fader (except the stereo master) has a SEL button in addition to the usual
MUTE and SOLO. The channel for which the CAM is active is selected by
pressing SEL. Only one SEL button can be selected at a time.
Thus, if the SEL button above Fader 5 is pressed, the CAM will adjust the

parameters of whatever signal is currently assigned to that fader. (Note that each

fader, and hence each SEL button, may be assigned to one of up to ve possible

10

5

0

signals within the mixer. This concept is discussed further under “Layers”, see

page 23.)

The controls on the CAM are now discussed in more detail:

Input stage:

48V

REV

HPF

TRIM - input gain trim.

48v – phantom power at the mic input.

REV – phase reverse.

HPF – variable-frequency high-pass lter.

HPF – high-pass lter frequency.

Dynamics section:

IN

GATE: THR – noise gate threshold.

GATE: IN – noise gate in/out.

IN

AUT

VIN

IN

COMP: THR – compressor threshold.

COMP: RAT – compressor ratio.

COMP: LVL – compressor gain make-up.

COMP: IN – compressor in/out.

COMP: AUT – sets compressor attack/release times automatically

IN

COMP: VIN – selects “vintage” compressor algorithm.

LIM: THR – limiter threshold.

LIM: IN – limiter in/out.

BYP – dynamics section in/out.

PST – dynamics section post-EQ.

DLY

SmS

IN

Delay section:

DLY – delay time.

DLY: IN – delay in/out.

Revision 1 2012-13 CDC FOUR

21

HI LO

FREQ

HF

WN

Q

HI LO

FREQ

HMF

WN

Q

HI LO

FREQ

LMF

WN

Q

HI LO

FREQ

LF

WN

Q

IN

-

+

dB

EQ Section:

HF: IN – HF EQ in/out.

HF: FREQ – EF EQ frequency.

HF: GAIN – HF EQ cut/boost.

IN

-

+

dB

HF: Q – HF EQ Q setting.

HF Shelf – HF EQ bell/shelf switch.

HMF: IN – HMF EQ in/out.

IN

-

+

dB

HMF: FREQ – HMF EQ frequency.

HMF: GAIN – HMF EQ cut/boost.

HMF: Q – HMF EQ Q setting.

LMF: IN – LMF EQ in/out.

IN

-

+

dB

LMF: FREQ – LMF EQ frequency.

LMF: GAIN – LMF EQ cut/boost.

LMF: Q – LMF EQ Q setting.

EQ

IN

LF: IN – LF EQ in/out.

LF: FREQ – LF EQ frequency.

LF: GAIN – LF EQ cut/boost.

AUX 1

AUX 2

AUX 3

AUX 4

AUX 5

AUX 6

AUX 7

AUX 8

LF: Q – LF EQ Q setting.

LF Shelf – LF EQ bell/shelf switch.

EQ IN – EQ section in/out.

0

ON

∞

PRE

0

ON

∞

PRE

0

ON

∞

PRE

0

ON

∞

PRE

0

ON

∞

PRE

Aux Sends:

AUX 1 – Aux. 1 send level.

AUX 1: ON – Aux. 1 on/off.

AUX 1: PRE – Aux. 1 pre/post.

AUX 2 – Aux. 2 send level.

AUX 2: ON – Aux. 2 on/off.

AUX 2: PRE – Aux. 2 pre/post.

AUX 3 – Aux. 3 send level.

AUX 3: ON – Aux. 3 on/off.

AUX 3: PRE – Aux. 3 pre/post.

0

ON

∞

PRE

0

ON

∞

PRE

0

ON

∞

PRE

AUX 4 – Aux. 4 send level.

AUX 4: ON – Aux. 4 on/off.

AUX 4: PRE – Aux. 4 pre/post.

AUX 5 – Aux. 5 send level.

AUX 5: ON – Aux. 5 on/off.

AUX 5: PRE – Aux. 5 pre/post.

AUX 6 – Aux. 6 send level.

AUX 6: ON – Aux. 6 on/off.

Revision 1 2012-13CDC FOUR

22

AUX 6: PRE – Aux. 6 pre/post.

AUX 7 – Aux. 7 send level.

AUX 7: ON – Aux. 7 on/off.

AUX 7: PRE – Aux. 7 pre/post.

AUX 8 – Aux. 8 send level.

AUX 8: ON – Aux. 8 on/off.

AUX 8: PRE – Aux. 8 pre/post.

FX 1

0

ON

∞

PRE

FX 2

0

ON

∞

PRE

0

3

6

9

12

15

18

24

36

54

LRGR

12

3

LR

LR

PAN

0

3

6

9

12

15

18

21

GT

LIM

4

IN

Internal FX Sends:

FX 1 – FX buss 1 send level.

FX 1: ON – FX 1 on/off.

FX 1: PRE – FX 1 pre/post.

FX 2 – FX buss 2 send level.

FX 2: ON – FX 2 on/off.

FX 2: PRE – FX 2 pre/post.

Routing and metering section:

1 – Group 1 routing button.

2 – Group 2 routing button.

3 – Group 3 routing button.

4 – Group 4 routing button.

L – stereo buss (left) routing button.

R – stereo buss (right) routing button.

PAN – channel pan control.

PAN: IN – Group panning in/out.

L METER – channel bargraph meter (left).

R METER – channel bargraph meter (right).

GR METER – dynamics section gain reduction bargraph meter.

GT – noise gate active LED.

LIM – limiter active LED.

SOLO

Mute and Solo:

SOLO – channel PFL/AFL/SIP solo button.

MUTE

Revision 1 2012-13 CDC FOUR

MUTE – channel mute button.

Layers

On an analogue mixer, the necessity for every channel (input or output) to have

its own set of controls and electronic hardware inevitably means that the physical

size of the mixer becomes proportional to the number of channels. An analogue

mixer with many inputs and outputs has a very large “footprint”.

This relationship may be dispensed with in a digital mixer, which allows a small
control surface to control large mixer congurations.

On the CDC FOUR, in 19” of control surface width, sixteen faders can control
up to 48 mic/line and 8 stereo inputs, plus eight Aux sends, eight VCA masters,

two internal FX returns and four output groups. This is achieved by arranging all

these various fader-controlled channels into ve* layers. Only one layer at a time
is active; the faders, with their associated MUTE, SOLO and SEL buttons control

the sixteen channels in that layer.

NOTE: The red MASTER fader always controls the main stereo output – it is not
part of any layer.

23

LAYER SELECT

CHNS
1 - 16

CHNS

VCA

The active layer is selected by the ve LAYER SELECT buttons ([7] on “Top view

CHNS

CHNS

33 - 48

17 - 32

ST

OUTPUTS

- control surface” on page 13).

The rst three layers make mic/line inputs 1-16, 17-32 and 33-48 respectively

available to the fader set. The layers corresponding to mic/line inputs 17 and
above will only be operative if the CDC RACK stagebox is connected to the mixer.
The fader assignments for the mic/line input layers are printed on the fader panel
above the faders.

The remaining two layers assign a combination of stereo inputs, VCA masters,
group outputs, Aux sends and FX masters to the fader set. The fader assignments

for these layers are printed on the fader panel below the faders.

* The faders may also be assigned to control the 1/3-octave graphic equaliser available to the main

stereo output; this effectively consitutes two additional layers.

Revision 1 2012-13CDC FOUR

24

The table below summarises the signal which each fader controls in each layer:

LAYER SELECT BUTTON

FADER CHNS 1-16 CHNS 17-24 CHNS 33-48 ST CHNS VCA OUTPUTS

1 Mic/line input 1 Mic/line input 17 Mic/line input 33 Stereo input 1 Output group 1

2 Mic/line input 2 Mic/line input 18 Mic/line input 34 Stereo input 2 Output group 2

3 Mic/line input 3 Mic/line input 19 Mic/line input 35 Stereo input 3 Output group 3

4 Mic/line input 4 Mic/line input 20 Mic/line input 36 Stereo input 4 Output group 4

5 Mic/line input 5 Mic/line input 21 Mic/line input 37 Stereo input 5 Aux Send Master 1

6 Mic/line input 6 Mic/line input 22 Mic/line input 38 Stereo return 1 Aux Send Master 2

7 Mic/line input 7 Mic/line input 23 Mic/line input 39 Stereo return 2 Aux Send Master 3

8 Mic/line input 8 Mic/line input 24 Mic/line input 40 Tape return Aux Send Master 4

9 Mic/line input 9 Mic/line input 25 Mic/line input 41 VCA master 1 Aux Send Master 5

10 Mic/line input 10 Mic/line input 26 Mic/line input 42 VCA master 2 Aux Send Master 6

11 Mic/line input 11 Mic/line input 27 Mic/line input 43 VCA master 3 Aux Send Master 7

12 Mic/line input 12 Mic/line input 28 Mic/line input 44 VCA master 4 Aux Send Master 8

13 Mic/line input 13 Mic/line input 29 Mic/line input 45 VCA master 5 FX Master 1

14 Mic/line input 14 Mic/line input 30 Mic/line input 46 VCA master 6 FX Master 2

15 Mic/line input 15 Mic/line input 31 Mic/line input 47 VCA master 7 -

16 Mic/line input 16 Mic/line input 32 Mic/line input 48 VCA master 8 -

The SEL button for each fader - and hence the entire Central Assignment Module
– follows the currently selected layer. Thus pressing the SEL button above Fader

5 will assign the CAM to mic/line input 5 when the layer CHNS 1-16 is active, but
to mic/line input 21 if the next layer, CHNS 17-32, is active, and to stereo input 5

if the layer ST CHNS VCA is active.

Every channel parameter for all the channels in a layer retains its last value when

the active layer is changed. This means that all levels, EQ settings, sends, etc.,

adjusted for a particular input will stay exactly as they are when you change to
a different layer. Although the fader set and CAM are now assigned to mic/line

inputs 17-32, it is possible to check and adjust parameters in mic/line inputs 1-16

– or any other layer – through the TFT display. Note that as the active layer is

changed, the motorised faders will automatically move to the correct positions for

the new layer.

Revision 1 2012-13 CDC FOUR

CENTRAL CONTROL MODULE

USB

METERS

SCENE

FX

25

Screen displays - overview

The TFT screen in the Central Control Module displays various information about
the current status of the mixer. The screen may be switched to display any one of

several pages, each of which is concerned with a particular set of mixer functions.

There are six pages available, selected by the page select buttons to the left of

the display:

CHN: this is the default view.

ROUTE

SYSTEM

CHN

The screen shows a representation of a single channel strip. Every control on

the CAM has a “virtual” equivalent on the display, and the page layout follows the
conventional signal ow through a channel. It is divided into ve vertical strips, the
rst four of which follow the layout of controls on the CAM. The fth (rightmost)

page strip shows the channel fader and VCA assignment.

The on-screen display always follows the SEL and LAYER selection; thus the
screen provides conrmation of the control settings for the currently selected

channel.

Because the rotary controls in the CAM are 360° encoders, their physical position
is not an indication of the parameter value (as would be the case on an analogue

mixer). However, the Channel page shows all current parameter values. Switch

settings are displayed in textual format and rotary controls are represented as
“analogue” 300° potentiometers, with the actual parameter value alongside in
text.

Revision 1 2012-13CDC FOUR