Century Series LM Owner's Manual

CENTURY SERIES

OWNER'S MANUAL

LM

Congratulations on your purchase of a Century Series console. All of us at Crest Audio in Paramus, NewJersey, USA, support your decision, knowing your console contains the finest combination of design andmanufacture in the industry.

While your new Century Series console is one of the most feature-packed available, great effort has beenput into making it simple to operate.

This manual explains the functions of your new console, how they operate and how they relate to eachother. If properly cared for, your new console will provide you with trouble-free, sonically accurate mixingclear into the next Century and beyond.

Please keep the following contact information on hand:

Crest Audio Customer Service Dept.100 Eisenhower Drive

Paramus NJ 07652 USATEL 201.909.8700 FAX 201.909.8744

http://www.crestaudio.com

Crest Audio Inc.100 Eisenhower Dr., Paramus NJ 07652 USA

TEL: 201.909.8700 FAX: 201.909.8744http://www.crestaudio.com

Printed in USA

Feature Overview 2A brief description of the LM design, features and functions.

System Connections 3Contains diagrams illustrating conventional system connections.

Wiring Conventions 5Contains diagrams indicating how connectors for Crest consoles are wired.

Power Supply 6A description of the rack-mountable Century Series consoles power supply.

Power Connections 7A description of Crest console power connections.

Console Cooling 7A brief description of the dual-fan cooling setup.

LM-12 Input Module 8Profiles the LM-12 input module. The module is illustrated and described.

LM-20 (LM-8+4) Input Module 10Profiles the LM-20 (LM-8+4) input module. The module is illustrated and described.

LM-12 Output Module 13Profiles the LM-12 ouput module. The module is illustrated and described.

LM 8+4 Output Module 15Profiles the LM-8+4 output module. The module is illustrated and described.

LM-20 Output Module 17Profiles the LM-20 ouput module. The module is illustrated and described.

Master Module A 19Profiles the LM A-Master module. The module is illustrated and described.

Master Module B 21Profiles the LM B-Master module. The module is illustrated and described.

Technical Information Appendix AIncludes dimensions, specifications, console access details,user options, console block diagram, and rear panel layout.

Glossary Appendix BThe specific details of console operation are described here, alphabetically.

Schematics Appendix CThis appendix lists available LM console & power supply schematics.

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TABLE OF CONTENTS

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CENTURY SERIES

Feature OverviewThe Century Series was designed to have all the features andfunctions demanded by the modern music professional. Theengineers at Crest Audio have delivered the finest combinationof function and sonic accuracy in an affordable intuitive con-sole. The features listed below are common to all CenturySeries LM Consoles.

• SSM/PMI High quality devices on balancedmicrophone/line inputs and on all outputs for uncompro-mised audio quality and reliability. All IC’s within the audiopath are socket mounted for easy upgrade or service.

• The signal path is completely free of electrolytic capaci-tors and all internal audio connections are gold plated.

• Passive microphone splitters on every microphone input.

• 48 Volt switchable phantom power on all microphoneinputs.

• Optional transformers available on all microphone inputsand primary outputs.

• Dynamic Signal Present and multiple-sample- point Peakindicator LED’s are used on all input sections of the consoleas well as on all primary outputs.

• Mono/Stereo PFL system. When a stereo module is used,the signal is monitored in stereo while mono modules are mon-itored in mono.

• Standard frame sizes include 32, 40, 44, 52 and 64 modulepositions. Any frame size may be ordered short loaded for laterexpansion.

• The three banks of four rotary send controls each have anassociated Pre switch. This switch can be internally selected tooperate as pre EQ or pre Fader; this selection applies to allthree Pre switches on the module.

• Each of the twelve send controls can be internally selectedto operate in one of three modes: follow its associated Preswitch, always Pre or always Post.

• Mute system on input channels is designed to mute both preand post fader signals. When muted, PFL circuitry and, Peakand Dynamic Signal Present LED indicators remain fully oper-ational. This is a feature not available on many consoles at anycost.

• Four scene (A-D) mute system

• The EQ section includes an EQ IN switch with LED and a100Hz High Pass filter switch. The EQ itself offers four bands(LF-40-800Hz, LMF-100Hz-2kHz, HMF-400Hz-8kHz, HF-1.5k-20kHz) that are sweepable, providing full frequency con-trol with generous overlap. The high and low frequency bandsare selectable between Peaking and Shelving via internaljumpers.

• Each LM output Module (except those in the master mod-ule) has a ten-segment LED array, three-band sweepable EQ,EQ-In switch, variable high-pass filter, polarity reverse, Insertswitch, Talkback enable, Dim, Peak & dynamic Signal PresentLEDs, local Mute and PFL.

• Return level controls provide signal from Returns 1 and 2found on the Master section. The Sub Input controls deliversignal from outputs 11 and 12 which are selectable pre or postfader. This feature allows mixes 11 and 12 to be cross-mixedto all other outputs.

• Comprehensive Talkback section allows access to all pri-mary console outputs. External signals can also be assignedinto the talkback system.

• The basis of every Century console is signal integrity.From the input preamplifier's impressive EIN of -129 dBu, tocompletely balanced primary busing, the Century LM deliversone of the cleanest signals available at any cost. This signalpurity comes from using only the highest quality componentsin its innovative design. All inputs and outputs are electronical-ly balanced, the primary inputs and outputs have the option oftransformer isolation.

• UL/CE-approved external power supply over-designedwith ample current reserves. For the ultimate in fail-safe relia-bility, a back-up power supply can be linked to the primarysupply with only an inexpensive jumper cable. Externalswitching is not needed.

LIVE MONITOR CONSOLE

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CENTURY SERIES LM

System ConnectionsThe console is the nerve center of a sound system and controlsmost of the variables within a system. Proper connection andcomponent relationships are vital to assure accurate operationand results. The following diagrams illustrate conventional sys-tem connections.

Signal Processors

In

Out

BAL INSERT RTN

DIR OUT

INSERT SEND

BAL MIC IN

BAL LINE IN

BAL INSERT RTN

DIR OUT

INSERT SEND

BAL MIC IN

BAL LINE IN

BAL INSERT RTN

DIR OUT

INSERT SEND

BAL MIC IN

BAL LINE IN

BAL INSERT RTN

DIR OUT

INSERT SEND

BAL MIC IN

BAL LINE IN

Front of HouseConsole

FromStage

Microphones

Insert Send/Return Connection

Microphone Splitting

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Clip/Limit

Signal

Temp/DC

Active

Ch B

-1

0dB

-3-6

-10

-15

-30

-80

6001 Professional Power Amplifier

Ch A

-1

0dB

-3-6

-10

-15

-30

-80

Clip/Limit

Signal

Temp/DC

Active

Ch B

-1

0dB

-3-6

-10

-15

-30

-80

6001 Professional Power Amplifier

Ch A

-1

0dB

-3-6

-10

-15

-30

-80

Transmitters forIn-Ear Monitors

Receivers forIn-Ear Monitors

Floor Wedge Connection

Stereo In-Ear Monitor Connection

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12

3

PIN 1 = GROUND

PIN 2 = POSITIVE

PIN 3 = NEGATIVE

OUTPUT XLRINPUT XLR

PIN 3

PIN 1

PIN 2PIN 3

PIN 2

PIN 1

TIP - POSITIVE

RING - NEGATIVE

SLEEVE - GROUND

INPU

T

TIP - SEND

RING - RETURN

SLEEVE - GROUND

INSER

T

TIP - POSITIVE

RING - NEGATIVE

SLEEVE - GROUND

OU

TPU

T

Input Plug Polarities

Insert send & Insert return PolaritiesOutput Plug Polarities

Wiring ConventionsSince the same connectors are used throughout the professional audio industry, it is important to know how the connectors forCrest’s Century Series are wired. The wiring is as follows.

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Power SupplyCentury Series Consoles use a separate rack-mountable power supply which provides the specific voltages used by each console.Century Consoles make use of two different power supplies. The model and frame size of your particular console determineswhich of the two supplies should be used.

Model

LM

Supply Model XCVA04

Frame Size 24,32

Supply Model XCVA06

Frame Size 40,44,52,64

Power Supply

C O N S O L E S

+20V

-20V

+48V

+24V

Press to Reset

4AON

Designed & manufactured in the USA by:

A division of Crest Audio Inc.100 Eisenhower Dr.

Paramus, New Jersey 07652 USA

POWER OUT

POWER OUT

RISK OF ELECTRIC SHOCKDO NOT OPEN

CAUTION

AVIS : RISQUE DE CHOC ÉLECTRIQUE—NE PAS OUVRIR

WARNING TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK DO NOTEXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE.

ATTENTION! POUR ÉVITER LE RISQUE D'INCENDIE OU DE CHOCÉLECTRIQUE, NE PLACEZ PAS CET APPAREIL SOUS LA PLUIE OU Á

L'HUMIDITÉ

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2 145 3

Pin 1 +24VPin 2 +20VPin 3 AnalogPin 4 AnalogPin 5 DigitalPin 6 +48VPin 7 -20V

CONSOLEGROUND

CHASSISGROUND

MAXIMUM AC IN:XCVA04: 415 WATTSXCVA06: 825 WATTS

+ 48V @ 1+ 24V @ 6± 20V @ 6

Model XCVA06

Model XCVA04± 20V @ 4+ 24V @ 4

S/N

Supply IdentificationThe type of power supply can be identified by the model num-ber shown on the back of the chassis and panel label.

Power RequirementsThe Century Series power supplies have certain electricalrequirements to operate properly. If possible the power supplyshould be connected to a dedicated circuit. Should any otherappliance on the same circuit draw enough current to overloadthe circuit, the breaker or fuse will trip causing loss of powerto the console. Note the maximum current draw specificationsat right. Be sure that the circuit to which you connect the sup-ply can handle the draw. The power switch on the supply front panel is also a circuitbreaker, there is no power fuse. Should the supply ever shutdown, or trip at start up, simply push the switch to the off posi-tion and then on again.

Ground LinkingSafety Considerations - Each new power supply is shippedwith the AC third wire ground connected to the console chassisground. The connection is made at the rear of the power supplyunit. This is necessary for safety reasons so that exposed metalparts are grounded. In the event of a live conductor makingcontact with the console chassis or the power supply chassisthen the current will flow to ground without a safety hazardarising. Note that when the console is disconnected from thepower supply the chassis ground connection to AC third wireground is broken and safety protection is lost. For uninterrupt-ible grounding, in a fixed installation for example, make a con-nection directly to the console chassis from the safety ground.Disconnect the ground link on the rear of the power supply.This disconnects console ground from power supply AC thirdwire ground which would otherwise create a hum-loop.

Twin Supply OperationWhen twin supplies are in use for automatic back-up, then theground links on both supplies should be fitted. In a situationwhere the safety ground to the console chassis has been con-nected and the ground path via the power supply is causing ahum-loop, then disconnect the ground links on BOTH powersupplies.

Console and Power Supply GroundingConsole chassis ground is electrically connected to audioground, pin 1 of XLR connectors and 1/4" sockets and to theterminal ‘CONSOLE GROUND’ at the rear of the power sup-ply. The AC third wire connection in the power supply cableconnects the metal chassis of the power supply to safetyground. This connection should never be disturbed. Hazardousvoltages exist inside the power supply which require the caseto be grounded. When rack-mounted, the power supply groundmay transfer to the rack case thru the front fixing screws,though this connection is not reliable. When a console is con-figured within a complete sound system the grounding require-ments may call for the ground link to be disconnected. This ispermissible only when an alternative ground path has beenprovided. If in doubt seek theadvice of an experienced elec-trical engineer.

+48V @ 1A+24V @ 6A±20V @ 6A

Model XCVA06

Model XCPS-40±20V @ 4+24V @ 4

S/N

Power Supply ModelXCVA04XCVA06

Max Current Draw 120V/230V7A/4A9A/5A

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POWER OUT

POWER OUT


CAUTION




L'HUMIDITÉ

67

2 145 3


CONSOLEGROUND

CHASSISGROUND


+ 48V @ 1+ 24V @ 6± 20V @ 6

Model XCVA06

Model XCVA04± 20V @ 4+ 24V @ 4

S/N




POWER OUT

POWER OUT


CAUTION




L'HUMIDITÉ

67

2 145 3


CONSOLEGROUND

CHASSISGROUND


+ 48V @ 1+ 24V @ 6± 20V @ 6

Model XCVA06

Model XCVA04± 20V @ 4+ 24V @ 4

S/N

To AC Mains

To AC Mains

Interface Cable

To Console

Power ConnectionsThe connections to and from the power supply vary depending on your specific configuration. Multiple power supplies can bedaisy-chained to provide fail-safe protection in the event of a supply failure. When two or more supplies are used, they may beconnected to the same mains voltage since only one of the supplies will actually be feeding the console at any given time.

The connectors on the power supply are “smart” so that either one can be used as the console or interface connection.

Console CoolingA cooling fan configuration is included in all LM consoles except the LM-12 and the 32-chassis space LM Dual/Stereo models.Two fans (one at each end of the console) draw air in through the sides of the chassis (under the sidebars). Air is distributedthrough the chassis via a “vortex pan”, then proceeds up through the console modules, where the heated air exits the consolechassis.

Once the console is powered up, cooling fans remain on. A rear panel switch permits the fans to be set at low, medium or highspeeds.

There are no filters to change or clean. As with any console, use in dusty/unclean environments should be avoided.

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LM-12 INPUT MODULE The LM-12 input module is the primary input control for the LM-12 monitor console. It differs from the LM-20 input module onlyin the mix send section.

48V Phantom Power SwitchTurns on 48V Phantom Power as required by certain microphonesfor proper operation.

LINE SwitchSelects between the Balanced XLR Microphone Input connectorand the Balanced Line Input 1/4" TRS connector.

PAD SwitchIntroduces a -15 dB cut to the mic input signal.

GAIN ControlAdjusts input gain for proper signal level.

100Hz High Pass SwitchReduces all low frequency content at a 12db per octave rate refer-enced to 100Hz (-3db point).

Polarity Reverse SwitchInverts the polarity of both the microphone and line inputs.

Four-Band Sweep Equalizer ControlsThere are two knobs for each of the four bands. The inner knobcontrols the boost or cut; while the outer knob controls the centerfrequency. These center frequencies are printed on the chassisaround the outer knob.

EQ IN SwitchInserts the EQ section into the input channel signal. An associatedLED illuminates when the switch is down.

PRE Switch 1-4Toggles mix sends 1-4 between Post and the internally selectedPre state.

Mix Sends 1-4Adjusts signal level sent to output mixes 1-4





MUTE Switch with LEDMutes the channel and all sends except the insert send. Thisswitch does not affect the PFL switch or the Peak and SignalPresent LED indicators, The LED illuminates when the channel ismuted either from the local mute switch or the scene mute system.

20

10

6

30

60

100

40

1503

6

800

250

100

400

1

2K

1K

400

1.5 3

6

8K

3

2K

4

10

20K

+48V

100

EQ IN

HM

LM

PAD

LF

GAIN

HF

PRE

PRE

PRE

7

8

9

5

2

1

34 6

7

8

9

5

2

01

34 6

10

7

8

9

5

2

01

34 6

10

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5

2

01

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2

01

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5

2

01

34 6

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5

2

0

1

34 6

10

7

8

9

5

2

01

34 6

10

7

8

9

5

2

0

1

34 6

10

LINE

ø

5

6

7

8

1

2

3

4

9

MUTE

PFL

PEAK

SIG

0

5

10

30

40

20

PRE

PRE

7

8

9

5

2

01

34 6

10

7

8

9

5

2

01

34 6

10

7

8

9

5

2

01

34 6

10

7

8

9

5

2

01

34 6

10

7

8

9

5

2

01

34 6

10

7

8

9

5

2

01

34 6

10

7

8

9

5

2

01

34 6

10

7

8

9

5

2

01

34 6

10

7

8

9

2

0

1

3

10

SCENEMUTE

SELECT

A

B

C

D

SAFE

7

8

9

5

2

01

34 6

10

5

6

7

8

4

9

10

11

12

BAL INSRT RTN

DIR OUT

INSRT SND

BAL MIC IN

BAL MIC OUT

PIN 1LIFT

BAL LINE IN

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PFL SwitchSamples the channel’s signal pre-fader and allows for monitor-ing within the master section of the console. This signal is notaffected by the Mute Switch. When depressed, the signal levelcan be seen on the output 12 meter, and heard via the mixer’sheadphone or local monitor output. When this PFL Switch isdepressed, the channel PEAK LED indicator illuminates at alower intensity. When used as a status indicator of switch posi-tion, the Peak LED indicating circuit remains fully operationalby illuminating at a much higher intensity than when indicat-ing PFL status.

PEAK LED IndicatorIlluminates RED when any of the points monitored come with-in 3db of the clipping point. Signal is sampled after the inputpreamplifier stage, after the EQ section, and after the fader.

This LED also serves as a PFL ON indicator, but at a muchlower intensity than when it is used to indicate clipping.

SIGNAL PRESENT LEDThis green LED constantly displays level activity of the inputchannel by varying in intensity.

100mm FaderUsed for control of all outputs of the channel except thosesends selected pre fader. (The Insert Output level is not affect-ed by the fader position.)

Scene Mute AssignmentsAssign the input channel to any of the four scene mute groups.Scene mute combines with the module’s local mute button, andactuates the local mute LED.

Scene Mute Safe SwitchDisables any selected scene mute assignments. An associatedgreen LED indicates that the channel is in a safe state.

Rear Panel ConnectionsDirect OutThis 1/4-inch TRS jack carries the direct output signal (postfader & post mute) from the associated input channel.

Insert SendThis 1/4-inch TRS jack carries the send signal of the insertloop to the external effect or signal processor.

Balanced Insert ReturnThis 1/4-inch TRS jack accepts the return signal of the insertloop from the external effect or signal processor back into theconsole.

Balanced Line InThis 1/4-inch TRS jack accepts balanced and unbalanced linelevel inputs and delivers it into the associated input channel.

Lift Pin 1This ground lift switch may be used to isolate pin1 of the micXLR from console ground.

Unpressed = pin 1 grounded

Pressed = pin 1 lifted

Balanced Mic InThis XLR connector accepts balanced microphone inputs forthe associated input channel.

Balanced Mic OutThis XLR connector is in parallel with the Balanced Mic Inconnector and allows easy connection of the monitor board tothe FOH console.

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LM-20 (LM-8+4) INPUT MODULEThis module serves as the input module for LM-20 and the now-discontinued LM-8+4. The only difference between the two isthe factory default settings on the dual concentric sends.For theLM-20 the sends are set for level/level operation. For an LM-8+4 the sends are set for level/pan operation.

48V Phantom Power SwitchTurns on 48V Phantom Power as required by certain micro-phones for proper operation.

LINE SwitchSelects between the Balanced XLR Microphone Input connectorand the Balanced Line Input 1/4" TRS connector.

PAD SwitchIntroduces a -15 dB cut to the mic input signal.

GAIN ControlAdjusts input gain for proper signal level.

100Hz High Pass SwitchReduces all low frequency content at a 12db per octave rate ref-erenced to 100Hz (-3db point).

Polarity Reverse SwitchInverts the polarity of both the microphone and line inputs.

Four-Band Sweep Equalizer ControlsThere are two knobs for each of the four bands. The inner knobcontrols the boost or cut; while the outer knob controls the cen-ter frequency. These center frequencies are printed on the chas-sis around the outer knob.

EQ IN SwitchInserts the EQ section into the input channel signal. An associat-ed LED illuminates when the switch is down.


Mix Sends 1-4Adjusts signal level sent to stereo output mixes 1-4 or monomixes 1a through 4b.





20

10

6

30

60

100

40

1503

6

800

250

100

400

1

2K

1K

400

1.5 3

6

8K

3

2K

4

10

20K

+48V

100

EQ IN

HM

LM

PAD

LF

GAIN

HF

PRE

PRE

4

PRE

7

8

9

5

2

1

34 6

7

8

9

5

2

01

34 6

10

7

8

9

5

2

01

34 6

10

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5

2

01

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01

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5

2

0

1

34 6

10

7

8

9

5

2

01

34 6

10

7

8

9

5

2

0

1

34 6

10

LINE

ø

2

3

1

5

6

7

8

9

MUTE

PFL

PEAK

SIG

0

5

10

30

40

20

PRE

4

PRE

7

8

9

5

2

01

34 6

10

7

8

9

5

2

01

34 6

10

7

8

9

5

2

01

34 6

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01

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01

34 6

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8

9

5

2

01

34 6

10

7

8

9

2

0

1

3

10

SCENEMUTE

SELECT

A

B

C

D

SAFE

5

6

7

8

9

10

11

12

BAL INSRT RTN

DIR OUT

INSRT SND

BAL MIC IN

BAL MIC OUT

PIN 1LIFT

BAL LINE IN

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MUTE Switch with LEDMutes the channel and all sends. This switch does not affectthe PFL switch or the Peak and Signal Present LED indicators,The LED illuminates when the channel is muted either fromthe local mute switch or the scene mute system.

PFL SwitchSamples the channel’s signal pre-fader and allows for monitor-ing within the master section of the console. This signal is notaffected by the Mute Switch. When depressed, the signal levelcan be seen on the output 12 meter, and heard via the mixer’sheadphone or local monitor output. When this PFL Switch isdepressed, the channel PEAK LED indicator illuminates at alower intensity. When used as a status indicator of switch posi-tion, the Peak LED indicating circuit remains fully operationby illuminating at a much higher intensity than its use as a PFLstatus indicator.



SIGNAL PRESENT LEDConstantly displays level activity of the input channel by vary-ing in intensity.

100mm FaderUsed for control of all outputs of the channel except those Auxoutput sections selected by switch to a pre fader position. (TheInsert Output level is not affected by the fader position.)


Scene Mute Safe SwitchDisables any selected scene mute assignments. An associatedgreen LED indicates the channel is in a safe state.

Rear Panel ConnectionsDirect OutThis 1/4-inch TRS jack carries the direct output signal (postfader & post mute) from the associated input channel.

Insert SendThis 1/4-inch TRS jack carries the send signal of the insertloop to the external effect or signal processor.

Balanced Insert ReturnThis 1/4-inch TRS jack accepts the return signal of the insertloop from the external effect or signal processor back into theconsole.

Balanced Line InThis 1/4-inch TRS jack accepts balanced and unbalanced linelevel inputs and delivers it into the associated input channel.

Lift Pin 1This ground lift switch may be used to isolate pin1 of the micXLR from console ground.

Unpressed = pin 1 grounded

Pressed = pin 1 lifted

Balanced Mic InThis XLR connector accepts balanced microphone inputs forthe associated input channel.

Balanced Mic OutThis XLR connector is in parallel with the Balanced Mic Inconnector and allows easy connection of the monitor board tothe FOH console.

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CENTURY SERIES

OUTPUT

+9

+6

+3

0

-3

-6

-9

-12

-15

-18

1 1

8 8

O +

1 1

8 8

O +

SUBINPUT

1

1

HF

LF

10

4

15 30

6

1

60

30

1 3

5

8

7

8

9

5

2

01

34 6

1

7

8

9

5

2

01

34 6

1

3

1

51

1

20

1 1

8 8

O +MID

ø

EQ IN

HPF

4

2

8 10

20

40

RETURN

1

2

7

8

9

5

2

01

34 6

1

7

8

9

5

2

01

34 6

1

MUTE

PFL

PEAK

SIG

DIM

TB ENB

INSERTON

SUBINPUT

1

1

1

0

5

10

30

40

5

20

7

8

9

5

2

01

34 6

1

7

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01

34 6

1

ø

4

2

20

40

RETURN

1

2

7

8

9

5

2

01

34 6

1

7

8

9

5

2

01

34 6

1

BAL OUT

INSERT RTN

INSERT SEND

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CENTURY SERIES

LM-12 Output ModuleThe LM-Mono Group output module is the primary outputmodule on the LM-12 and the secondary output module on theLM-8+4 and the LM-20

Output MeterMonitors the post-fader output signal via a ten-segment LEDarray.

Output EQControls the the equalization of the output mix signal throughthree bands, via six controls. The upper knob of each banddetermines the center frequency (high-1kHz-20kHz, mid-300Hz-8kHz, low-40Hz, 1kHz), while the lower knob adjuststhe amount of boost or cut.

EQ IN SwitchInserts the EQ section into the output channel signal. An asso-ciated LED illuminates when the switch is down.

High Pass Filter SwitchInserts the High Pass Filter into the output signal.

HPF Frequency ControlThis knob adjusts the high pass filter frequency from 20Hz to400Hz. The filter operates at a -12 dB per octave rate.

Return Level ControlsAdjusts the level of return signals 1 and 2 in the output. Thesesignals come from the Master Section. See Returns 1 & 2 onthe Master Section description for more information.

Sub Input ControlsAdjusts the level of cross-mix in the output from mono outputs11 and 12.

Polarity Reverse SwitchInverts the polarity of the output.

Insert On SwitchTurns on the insert loop for the output signal. If a completeinsert loop is not present depressing this switch will mute theoutput.

TB Enable SwitchInjects the talkback signal from the master section into thegroup output.

DIM SwitchIntroduces a -6dB drop to the output signal. This is a pushon/push off switch, not momentary.

MUTE Switch with LEDMutes the output. This switch does not affect the PFL switchor the Peak and Signal Present LED indicators.

Output PFLEnables Pre Fader Listening of the output signal. (this signalcan be internally selected post fader)

Output PEAK & Signal LEDsThe red LED indicates that the output is within 3dB of the clip-ping point.

The green LED constantly displays the level of signal activityby varying in intensity.

Output FaderControls the final output signal level.

Rear Panel ConnectionsBalanced OutThis XLR connector carries the post-fader output signal fromthe associated output module.

Output Insert SendThis 1/4-inch TRS balanced jack carries the send signal of theoutput insert loop to the external effect or signal processor.

Output Insert ReturnThis 1/4-inch TRS balanced jack accepts the return signal ofthe output insert loop from the external effect or signal proces-sor.

LM

PAGE 14

CENTURY SERIES

MONO

OUTPUT

+9

+6

+3

0

-3

-6

-9

-12

-15

-18

16 16

8 8

O +

16 16

8 8

O +

SUBINPUT

11

12

HF

LF

100

40

150 300

6

1K

600

300

1K 3

5

8K

7

8

9

5

2

01

34 6

10

7

8

9

5

2

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34 6

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3

1K

5 10

15

20K

16 16

8 8

O +MID

Ø

EQ IN

HPF

40

20

80 100

200

400

RETURN

1

2

7

8

9

5

2

01

34 6

10

7

8

9

5

2

01

34 6

10

MONO

MUTE

PFL

PEAK

SIG

DIM

TB ENB

INSERTON

SUBINPUT

11

12

0

5

10

30

40

5

20

7

8

9

5

2

01

34 6

10

7

8

9

5

2

01

34 6

10

Ø

40

20

100

200

400

RETURN

1

2

7

8

9

5

2

01

34 6

10

7

8

9

5

2

01

34 6

10

INSERT RETURN

BAL OUT LEFT

INSERT SEND

INSERT RETURN

BAL OUT RIGHT

INSERT SEND

LM

PAGE 15

CENTURY SERIES

LM-8+4 Output ModuleThe LM-Stereo group output module is the primary outputmodule on the discontinued LM-8+4.

Output MetersMonitors the post-fader output signal via two ten-segmentLED arrays.

Output EQControls the the equalization of the output mix signal throughthree bands, via six controls. The upper knob of each banddetermines the center frequency (high-1kHz-20kHz, mid-300Hz-8kHz, low-40Hz, 1kHz), while the lower knob adjuststhe amount of boost or cut.




Return Level ControlsAdjusts the level of return signals 1 and 2 in the output. Thesesignals come from the Master Section. The center knob adjustslevel while the outer knob adjusts panning within the stereoimage. See Returns 1 & 2 on the Master Section description formore information.

Sub Input ControlsAdjusts the level of cross-mix in the output from mono outputs11 and 12. The center knob adjusts while the outer knobadjusts panning within the stereo image.

Mono SwitchDepressing this switch mixes the left and right pre-insert sig-nals together onto the Left Insert Send jack. The Left InsertReturn is switched to both Left and Right Returns. This allowsfor a mono processor to be used, but affect both channels.






Output PFLEnables Pre Fader Listening of the output signal. (this send canbe internally selected post fader)



Output FaderControls the final output signal level

Rear Panel Connections (L & R)Balanced OutThis XLR connector carries the post-fader output signal fromthe associated output module.



LM

PAGE 16

CENTURY SERIES

OUTPUT

+9

+6

+3

0

-3

-6

-9

-12

-15

-18

16 16

8 8

O +

16 16

8 8

O +

SUBINPUT

11

12

HF

LF

100

40

150 300

6

1K

600

300

1K 3

5

8K

7

8

9

5

2

01

34 6

10

7

8

9

5

2

01

34 6

10

3

1K

5 10

15

20K

16 16

8 8

O +MID

Ø

EQ IN

HPF

40

20

80 100

200

400

RETURN

1

2

7

8

9

5

2

01

34 6

10

7

8

9

5

2

01

34 6

10

A B

MUTE

PEAK

SIG

DIM

TB ENB

INSERT ON

SUBINPUT

11

127

8

9

5

2

01

34 6

10

7

8

9

5

2

01

34 6

10

Ø

40

20

200

400

RETURN

1

2

7

8

9

5

2

01

34 6

10

7

8

9

5

2

01

34 6

10

A B

PFL

0

5

10

30

40

5

20

INSERT RETURN

BAL OUT LEFT

INSERT SEND

INSERT RETURN

BAL OUT RIGHT

INSERT SEND

LM

PAGE 17

CENTURY SERIES

LM-20 Output ModuleThe LM-Dual group output module is the primary output mod-ule on the LM-20.

Output MeterMonitors the post-fader output signal via two ten-segmentLED arrays.

Output EQControls the the equalization of the output mix signal throughthree bands, via six controls. The upper knob of each banddetermines the center frequency (high-1kHz-20kHz, mid-300Hz-8kHz, low-40Hz, 1kHz), while the lower knob adjuststhe amount of gain or cut. This single set of knobs controlsboth channels A & B.



HPF Frequency ControlThis knob adjusts the high pass filter frequency from 20Hz to400Hz. The filter operates at a -12 dB per octave rate. This sin-gle knob controls both channels A & B.

Return Level ControlsAdjusts the level of return signals 1 and 2 in the output. Thesesignals come from the Master Section. The center knob adjusts“level A” while the outer knob adjusts “level B.” See Returns 1& 2 on the Master Section description for more information.

Sub Input ControlsAdjusts the level of cross-mix in the output from mono outputs11 and 12. The center knob adjusts “level a” while the outerknob adjusts “level b.”






Output PFLEnables Pre Fader Listening of the output signal. (This sendcan be internally selected post fader)



Output FadersControls the final output level of each signal (a & b).

Rear Panel Connections (L & R)Balanced OutThis XLR connector carries the post-fader output signal fromthe associated output module.



LM

PAGE 18

CENTURY SERIES

OUTPUT

MONITOR A LEFT

MONITOR A RIGHT

BAL OUT

EXT TB IN

INSERT RTN

INSERT SEND

LM

PAGE 19

CENTURY SERIES

LM Master Module AThis the first of two modules that include master controls forall LM consoles in addition to mono output eleven.

Output MeterMonitors the post-fader output signal of group 11 via a ten-segment LED array.

Monitor Level AAdjusts the output level of local monitors A.

Monitor Mute AMutes local monitor A.

Sub 11 Post SwitchSwitches the subgroup send between pre and post fader.

Sub 11 On SwitchSwitches the subgroup send on and off.

Lamp Dim ControlControls the brightness of any 12 volt lighting devices attachedto the XLR connectors on the light bar.

Power IndicatorsShows the status of the four voltages used by the console.

Phantom Master Switch w/LEDSwitches +48V phantom power on and off for the entire con-sole.

Input/Output PFL IndicatorsThese LEDs indicate what type of signal (input or output) isPFL’d at any given time. Input PFL always gets priority overoutput PFL.

Input Fader Mix SwitchSums all input mixes and assigns the summed signal to theMonitor A output. This output is stereo when stereo signals arepresent. This signal is post fader.

Return Master Peak & Signal LEDsThe red LED indicates that the output is within 3dB of the clip-ping point. The green LED constantly displays the level of sig-nal activity by varying in intensity.

Return Master PFL SwitchPFLs the return signal.

Return Master MuteMutes the return signal

Return Master Level ControlsControls the final return signal level.

Output 11 Polarity Reverse Inverts the polarity of outputs 11.

Output 11 Insert On SwitchTurns on the insert loop for the output signal. If a completeinsert loop is not present depressing this switch will mute theoutput.

Output 11 Talkback Enable Injects the talkback signal from the master section into thegroup output.

Output 11 Dim SwitchIntroduces a -6dB drop to the output signal. This is a pushon/push off switch, not momentary.

Output 11 Mute SwitchMutes the output. This switch does not affect the PFL switchor the Peak and Signal Present LED indicators.

Output 11 PFL SwitchEnables Pre Fader Listening of the output signal. (This can beinternally selected to post fader)

Output 11 Peak & Signal LEDsThe red LED indicates that the output is within 3dB of the clip-ping point. The green LED constantly displays the level of sig-nal activity by varying in intensity.

Output 11 100mm FadersControls the final signal level of outputs 11.

Rear Panel ConnectionsOutput 11 Bal OutThis XLR connector carries the post-fader output signal fromthe output group 11

Insert SendThis 1/4-inch TRS balanced jack carries the send signal of theoutput insert loop to the external effect or signal processor.

Insert ReturnThis 1/4-inch TRS balanced jack accepts the return signal ofthe output insert loop from the external effect or signal proces-sor.

Monitor A Out (L&R)These two connectors deliver local monitor A ‘s balanced out-put signal.

Oscillator / Pink Noise InThis 1/4-inch connector accepts a balanced or unbalanced sig-nal from an oscillator or pink noise generator. This signal isassignable via the talkback assignment switches.

LM

PAGE 20

CENTURY SERIES

OUTPUT

INSERT RTN

MONITOR B LEFT

MONITOR B RIGHT

BAL OUT

OSC IN

INSERT SEND

LM

PAGE 21

CENTURY SERIES

LM Master Module BThis the second of two modules that include master controlsfor all LM consoles in addition to mono output twelve.

Output MeterMonitors the post-fader output signal of group 12 via a ten-segment LED array. This meter also indicates PFL level.

PFL IndicatorThis LED illuminates when the signal on meter 12 is a PFL orAFL signal

Talkback Mic InputAllows for connection of a gooseneck or other XLR typemicrophone to the talkback system. Phantom power is avail-able here for condenser mics.

Headphone JackAllows for connection of headphones via a 1/4" TRS plug.

Headphone Level ControlControls the output level of both headphone jacks.

Group Mix SwitchSums all output mixes and assigns the summed signal to theMonitor B output. This output is stereo when stereo signals arepresent. This signal is post fader.

Monitor Level BAdjusts the output level of local monitor B.

Monitor Mute BMutes local monitor B.

Oscillator OnSwitches on the internal 1kHz oscillator. The internal oscillatoronly operates when the Talkback system is engaged.

External TB Input SwitchAdds an external signal to the internal talkback signal. Thissignal is patched in via the external talkback connector on theback of the master module.

Talkback Level ControlAdjusts the final level of all talkback signals.

External TB Output SwitchFeeds signal to the external talkback output connection. Onlythe internal talkback signal is present at this connector.

Talkback Master On/OffSwitches the internal talkback system on and off

Sub 12 Post SwitchSwitches the subgroup send between pre and post fader.

Sub 12 On SwitchSwitches the subgroup send on and off.

Output 12 Polarity Reverse Inverts the polarity of output 12.

Output 12 Insert On SwitchTurns on the insert loop for the output signal. If an incompleteinsert loop is present, depressing this switch will mute the out-put

Output 12 Talkback Enable Injects the talkback signal from the master section into thegroup output.

Output 12 Dim SwitchIntroduces a -6dB drop to the output signal. This is a pushon/push off switch, not momentary.

Output 12 Mute SwitchMutes the output. This switch does not affect the PFL switchor the Peak and Signal Present LED indicators.

Output 12 PFL SwitchEnables Pre Fader Listening of the output signal. (This can beinternally selected to post fader)

Output 12 Peak & Signal LEDsThe red LED indicates that the output is within 3dB of the clip-ping point. The green LED constantly displays the level of sig-nal activity by varying in intensity.

Output 12 100mm FaderControls the final signal level of outputs12.

Scene Mute MastersThese four switches turn the four scene mutes on and off forthe entire console.

Rear Panel ConnectionsOutput 12 Bal OutThis XLR connector carries the post-fader output signal fromthe output group 12.

Insert SendThis 1/4-inch TRS balanced jack carries the send signal of theoutput insert loop to the external effect or signal processor.

Insert ReturnThis 1/4-inch TRS balanced jack accepts the return signal ofthe output insert loop from the external effect or signal proces-sor.

Monitor B Out (L&R)These two connectors deliver local monitor B ‘s balanced out-put signal.

Ext. Talkback InThis connector accepts a balanced signal which is assignable toany of the locations in the talkback system.

Appendix A

TechnicalInformation

LM

LM

APPENDIX A

CENTURY SERIES

SpecificationsThe following are the technical specifications for the CenturyLM console.

Frequency Response+0.0, -0.5dB, 20Hz to 20 kHz (referenced to 1kHz)

Total Harmonic DistortionMic input to Group output20Hz to 20 kHz at +15dBu <0.01%

Noise (22Hz to 22kHz)Mic EIN -129 dBuGroup Output Noise (20 ch routed)- 80 dBu

Crosstalk (Measured at 1kHz)Channel Mute >102 dBChannel Fader Attenuation > 96 dBChannel Routing > 85 dB

Input/Output ImpedancesMic Input 4kΩ balancedLine Input >10kΩ balancedOutputs 140Ω balanced

Input/Output Levels (0VU = +4 dBu, 1.23V RMS)Mic Input Sensitivity + 4 to -62 dBuLine Input Sensitivity + 12 to -38 dBuInput Insertion Point Level + 4 dBuOutput Insertion Point Level - 2 dBuNominal Output Level + 4 dBuMaximum Balanced Output Level +28 dBu

LM-12 (12 mono outputs)12, 20, 28, 32, 40, or 52 inputs

LM-20 (20 mono outputs)12, 20, 28, 32, 40, or 52 inputs

ConfigurationsCentury LM Consoles are availablein the following configurations:

Architect’s & Engineer’sSpecificationsThe following text should be used when specifying a CenturyLM in a bid or proposal.

The monitor console shall be constructed in a modular fashionand be housed in a steel frame with molded plastic sidepanel/carrying handles. The console shall be black with whitelabeling and utilize XLR lighting device connectors. Allmicrophone inputs shall be electronically balanced andaccessed via 3-pin XLR connectors and have an EIN of -129dBm. All line inputs shall be electronically balanced andaccessed via 1/4" TRS jacks. The insert points shall have dis-crete send and return connectors. Each input channel shallhave: a +48 volt phantom power switch, a -15 dB mic padswitch, a 100Hz high pass filter switch, a polarity reverseswitch and 4-band (LF-40-800Hz, LMF-100Hz-2kHz, HMF-400Hz-8kHz, HF-1.5k-20kHz) sweepable EQ with selectablepeak/shelve settings on the high and low controls and an EQIn switch. Each input channel shall also have: a FET con-trolled (10 millisecond ramp) mute switch with LED, dynamicsignal present LED and peak LED, 4 scene mute switches (A-D) each with LED, scene mute safe switch with LED and a100mm long throw fader. Each input channel shall have outputsend controls appropriate to the specified model. Each bank offour rotary controls shall have an associated pre switch whichshall be internally elected to operate as pre EQ or pre Fader;this selection shall apply to all three pre switches on the input.Each of the send controls shall be internally selectable to oper-ate in one of three modes: follow its associated pre switch,always pre or always post. The console shall be available intwo output configurations: 12 mono or 20 mono. Each outputshall have a ten-segment LED array, three-band sweepableEQ, EQ-In switch, variable high-pass filter, polarity reverse,insert switch, talkback enable, dim, peak & dynamic signalpresent LEDs, local mute and PFL. The mono outputs shallhave mono EQ, the stereo outputs shall have stereo EQ; whilethe dual mono outputs shall have stereo EQ but with separateA/B EQ In switches. The master section shall be containedwithin mono outputs 11 and 12 and shall contain: a talkbacksystem, scene mute master controls, return master controls andtwo stereo local monitor controls, connections for headphones,talkback mics, external oscillators as well as indicators forpower, input and output PFL. The power supply shall behoused in a 14 ga. steel chassis that shall occupy two 19" rackspaces. The power supply shall have the ability to be daisy-chained to additional power supplies to provide a fail-safeoperating environment. Connection of two or more power sup-plies shall not require additional interface hardware other thanthe provided cable.The live monitor console shall be: the CrestAudio Century LM.

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LM Block Diagram

LM CENTURY SERIES

APPENDIX A

LM

APPENDIX A

CENTURY SERIES

Console

Sid

e D

imensio

ns

The follow

ing diagram illustrates the depth and height dim

en-sions (from

the side) for all Century L

M consoles.

2.25"/57mm

KN

OB

HE

IGH

T 0.75"/19m

m &

1.25"/32mm

24.75"/ 717mm

28.0"/ 711mm

29.563" / 751mm

29.625"/752mm

10.25"/260mm

6.25"/159mm3.25"/83m

m

9.5"241m

m

2.437"62m

m

1.125"/29mm

2.375"/60mm

35°

All inform

ation per

Crest C

onsoles Engineering,

May 5, 1997

LM

APPENDIX A

CENTURY SERIES

Console Rear Views and Dimensions

A

B

.75in.19mm

1.5in./38mm

Size A B24 33.55" 31.80"32 43.15" 41.40"40 52.75" 51.00"44 57.55" 55.80"52 67.15" 65.40"64 81.55" 79.80"

Size A B24 852mm 808mm32 1096mm 1052mm40 1340mm 1295mm44 1462mm 1417mm52 1706mm 1661mm64 2071mm 2027mm

Crest Consoles Engineering,May 5, 1997

INSER

T R

ETU

RN

MON

ITOR

A L

EFT

BAL

OU

T

INSER

T SEN

D

EXT

TB IN

INSER

T R

ETU

RN

MON

ITOR

B L

EFT

MON

ITOR

B R

IGH

T

BAL

OU

T

INSER

T SEN

D

OSC IN

MON

ITOR

A R

IGH

T

BAL

OU

T

INSER

T SEN

D

INSER

T R

ETU

RN

RET

UR

N 1

RET

UR

N 2

EXT

TB O

UT

BAL

OU

T

INSER

T SEN

D

INSER

T R

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RN

INSER

T SEN

D

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T SEN

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BAL

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FT

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T R

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RN

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T R

IGH

TB

AL

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T R

IGH

T

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T R

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RN

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T R

IGH

T

INSER

T SEN

D

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BAL

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T LE

FT

INSER

T SEN

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T R

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IGH

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T SEN

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D

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T LE

FT

INSER

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D

INSER

T R

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RN

BAL

OU

T R

IGH

T

INSER

T SEN

D

INSER

T R

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RN

BAL

OU

T LE

FT

INSER

T SEN

D

INSER

T R

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RN

BAL

OU

T R

IGH

T

INSER

T SEN

D

INSER

T R

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RN

INSER

T SEN

D

DIR

OU

TD

IR O

UT

DIR

OU

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IR O

UT

DIR

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TD

IR O

UT

DIR

OU

TD

IR O

UT

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OU

TD

IR O

UT

DIR

OU

TD

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UT

DIR

OU

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IR O

UT

DIR

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UT

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OU

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IR O

UT

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UT

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OU

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UT

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UT

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TD

IR O

UT

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OU

TD

IR O

UT

DIR

OU

TD

IR O

UT

BAL

INSR

T R

TN

INSR

T SN

D

BAL

MIC

IN

BAL

MIC

OU

T

LIFT

PIN

1

BAL

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E IN

BAL

INSR

T R

TN

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T SN

D

BAL

MIC

IN

BAL

MIC

OU

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LIFT

PIN

1

BAL

LIN

E IN

BAL

INSR

T R

TN

INSR

T SN

D

BAL

MIC

IN

BAL

MIC

OU

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LIFT

PIN

1

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E IN

BAL

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TN

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D

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MIC

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BAL

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1

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TN

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IN

BAL

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OU

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PIN

1

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E IN

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TN

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D

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MIC

IN

BAL

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OU

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PIN

1

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1

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1

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T SN

D

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MIC

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BAL

MIC

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1

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T SN

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BAL

MIC

OU

T

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PIN

1

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E IN

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T SN

D

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MIC

IN

BAL

MIC

OU

T

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PIN

1

BAL

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E IN

BAL

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T SN

D

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MIC

IN

BAL

MIC

OU

T

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PIN

1

BAL

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INSR

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TN

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T SN

D

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MIC

IN

BAL

MIC

OU

T

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PIN

1

BAL

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BAL

INSR

T R

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INSR

T SN

D

BAL

MIC

IN

BAL

MIC

OU

T

LIFT

PIN

1

BAL

LIN

E IN

BAL

INSR

T R

TN

INSR

T SN

D

BAL

MIC

IN

BAL

MIC

OU

T

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PIN

1

BAL

LIN

E IN

BAL

INSR

T R

TN

INSR

T SN

D

BAL

MIC

IN

BAL

MIC

OU

T

LIFT

PIN

1

BAL

LIN

E IN

BAL

INSR

T R

TN

INSR

T SN

D

BAL

MIC

IN

BAL

MIC

OU

T

LIFT

PIN

1

BAL

LIN

E IN

BAL

INSR

T R

TN

INSR

T SN

D

BAL

MIC

IN

BAL

MIC

OU

T

LIFT

PIN

1

BAL

LIN

E IN

BAL

INSR

T R

TN

INSR

T SN

D

BAL

MIC

IN

BAL

MIC

OU

T

LIFT

PIN

1

BAL

LIN

E IN

BAL

INSR

T R

TN

INSR

T SN

D

BAL

MIC

IN

BAL

MIC

OU

T

LIFT

PIN

1

BAL

LIN

E IN

BAL

INSR

T R

TN

INSR

T SN

D

BAL

MIC

IN

BAL

MIC

OU

T

LIFT

PIN

1

BAL

LIN

E IN

BAL

INSR

T R

TN

INSR

T SN

D

BAL

MIC

IN

BAL

MIC

OU

T

LIFT

PIN

1

BAL

LIN

E IN

BAL

INSR

T R

TN

INSR

T SN

D

BAL

MIC

IN

BAL

MIC

OU

T

LIFT

PIN

1

BAL

LIN

E IN

BAL

INSR

T R

TN

INSR

T SN

D

BAL

MIC

IN

BAL

MIC

OU

T

LIFT

PIN

1

BAL

LIN

E IN

BAL

INSR

T R

TN

INSR

T SN

D

BAL

MIC

IN

BAL

MIC

OU

T

LIFT

PIN

1

BAL

LIN

E IN

BAL

INSR

T R

TN

INSR

T SN

D

BAL

MIC

IN

BAL

MIC

OU

T

LIFT

PIN

1

BAL

LIN

E IN

BAL

INSR

T R

TN

INSR

T SN

D

BAL

MIC

IN

BAL

MIC

OU

T

LIFT

PIN

1

BAL

LIN

E IN

BAL

INSR

T R

TN

INSR

T SN

D

BAL

MIC

IN

BAL

MIC

OU

T

LIFT

PIN

1

BAL

LIN

E IN

BAL

INSR

T R

TN

INSR

T SN

D

BAL

MIC

IN

BAL

MIC

OU

T

LIFT

PIN

1

BAL

LIN

E IN

Mas

ter

Sec

tion

Out

puts

Inpu

ts

LM

APPENDIX A

CENTURY SERIES

LM USER-OPTIONS

LM Consoles are shipped having standard configuration unless specified at time of order There are ways that the console config-uration may be varied after manufacture. The items listed are internal options selected by gold jumper links.Default is marked with a line on the board and is usually pins 1&2 of the three pin header.In addition there are links for module function assignment. Take care to not disturb these when using USER OPTION links.

MODULE LOCATION OPTION TITLE FUNCTION

M = MainC = Connector

Shipped with the option underlined

All modelsLM Inputs M Pre Source (SRC)Mute Aux sends with or without Mute

M Pre Source Select Pre & Post EQLM In EQ M HF PK-SH &LF PK-SH HF& LF Peak or Shelf EQLM Input C Mic Split Ground Connect or isolate Input pin 1 to Out pin 1

All modelsLM Output 11(master A) M Monitor A Out PFL Source Stereo or MonoLM Output 11 M Sub Send A Pre or Post group 11 InsertLM Output 12 (master B) M Sub Send B Pre or Post group 12 InsertLM Output 12 C Talkback Gain Low, Normal or HighLM Output 12 C Talkback Phantom Power On or Off

LM Stereo (8+4) modelsLM8+4 In, send pots M Stereo or Dual Mono switch Level+Pan or Level+LevelLM8+4 In, send pots M Group Source Selects 1-12 Pre/Post fader or SwitchedLM Stereo Groups M OPT 1 & 2 PFL or AFL Left & Right

LM Dual Mono (LM20) modelsInputs, send pots M Stereo or Dual Mono switch Level+Pan or Level+LevelInputs, send pots M Group Source Selects 1-12 Pre/Post fader or SwitchedLM Dual Mono Groups M Cue SEL opt 1 & 2 PFL or AFL A & B outputs

M CUE MODE opt 3 & 4 STR (stereo) or MONOM SUB A & B (switch 16, 17) Level+Pan or Level+LevelM RET A & B (switch 18, 19) Level+Pan or Level+Level

LM12 modelsLM 12 Outputs 1-10 M Cue, OPT 1 PFL or AFL

IMPORTANT

Output modules are pre-assigned at the Crest factory

These modules must always be installed in the correct positions. They are NOT interchangeable without being properly re-assigned. Please contact the Crest Audio Service Department for more information.

LM

APPENDIX A

CENTURY SERIES

Console DisassemblyThough you shouldn’t have to disassemble the console, it isnecessary to remove modules to change the jumper and switchsettings associated with the internally selectable options.ALWAYS DISCONNECT THE POWER SUPPLYBEFORE OPENING THE CONSOLE!

ONE•Releasing the armrest.To properly remove one or more modules, the black paintedarmrest must first be released. To do this, the two thumb-screws (see diagram at right) must be loosened from below.Once these screws are loose, slide both of them a few inch-es to the side (they will only move in one direction). Oncethe screws have been moved the armrest will easily rollback exposing the module screws beneath.

TWO•Remove top module screwOnce the armrest has been rolled back, a single screw hold-ing each module in place will be exposed. Remove thescrews from the module(s) you want to remove.

THREE•Remove rear screwsOn the back panel of the console there are two screws hold-ing each module in place (see diagram at right) Removeboth screws from each module you wish to remove.

FOUR•Lift the module(s) outAs you lift the module out of the chassis three wires mustbe detatched before the module can be completely removed:2 ribbon cables and one ground wire.The ribbon cables are removed by flipping the latches onthe ends of the connectors. Once the latches have beenflipped the connector should pull off easily.The ground wire (green) is a spade lug which will pull offwith a tug.

FIVE•Putting it all back togetherRe-assembling a Century LM is as easy as taking it apart, but only if you know where everything goes. If you are going to beremoving a number of modules, consider replacing the first before removing the second. Reversing the above steps will result inthe console being as well put together as it was when it left the factory.

Opening theArmrest

Thumbscrews

INSERT RETURN

MONITOR A LEFT

BAL OUT

INSERT SEND

EXT TB IN

INSERT RETURN

MONITOR B LEFT

MONITOR B RIGHT

BAL OUT

INSERT SEND

OSC IN

MONITOR A RIGHT

BAL OUT

INSERT SEND

INSERT RETURN

RETURN 1

RETURN 2

EXT TB OUT

BAL OUT

INSERT SEND

INSERT RETURN

BAL INSRT RTN

DIR OUT

INSRT SND

BAL MIC IN

BAL MIC OUT

LIFTPIN 1

BAL LINE IN

BAL

DIR

INSR

BAL

BAL

LIFTPIN

BAL

Upper Screw

INSERT RETURN

BAL OUT LEFT

INSERT SEND

INSERT RETURN

BAL OUT RIGHT

INSERT SEND

INSERT RETURN

BAL OUT LEFT

INSERT SEND

INSERT RETURN

BAL OUT RIGHT

INSERT SEND

Lower Screw

Light Bar

IMPORTANT

Output modules are pre-assigned at the Crest factory

These modules must always be installed in the correct positions. They are NOT interchangeable without being properly re-assigned. Please contact the Crest Audio Service Department for more information.

Appendix B

Glossary

LM

LM

APPENDIX B

CENTURY SERIES

GlossaryBalanced Insert Return See Insert Return

Balanced Line InSee Line Input

Balanced Mic InSee Microphone Input

Balanced Mic Out See Microphone Output

Balanced Out See Outputs

DIM SwitchIntroduces a -6dB drop to the output signal. This is a pushon/push off switch allows the operator to temporarily drop thelevel of a monitor without actually changing any settings.

Direct OutThis jack carries the direct output signal (post fader & postmute) from each input channel. This signal can be used forconnection to recording devices or routing of the post fadersignal.

EQ IN SwitchInserts the EQ section into the input/output channel signal. Anassociated LED illuminates when the switch is down.

Equalizer Controls (Input)There are two knobs for each of the four bands. The inner knobcontrols the boost or cut; while the outer knob controls the cen-ter frequency adjusted by the inner knob. These center frequen-cies are printed on the chassis around the outer knob. This EQis active only when the EQ In switch is depressed.

Equalizer Controls (Output)Controls the equalization of the output mix signal throughthree bands, via six controls. The upper knob of each banddetermines the center frequency (high-1kHz-20kHz, mid-300Hz-8kHz, low-40Hz, 1kHz), while the lower knob adjuststhe amount of boost or cut.

External Talkback InputIn addition to the mic connections on the console surface, anadditional Talkback input connection is provided on the rear ofthe master section. Signal connected to this jack appears on theTalkback bus whenever the External TB Input switch isdepressed.

External Talkback Output

This allows the internal TB signals present on the Talkbackbus to be routed to an external destination such as a link to theFOH console. Signal appears on this jack when both theExternal TB Output switch and talkback master switches aredepressed.

FaderUsed for final output control of an input/output channel exceptthose sends selected pre fader. (Insert Output levels are notaffected by the fader position.)

Gain ControlAdjusts input gain for proper signal level on the input. To setthe gain to the best position, make sure there is signal presentat the input. Depress the PFL switch on that input channel andmake sure that no other PFL switches are depressed. Adjust thegain control until the PFL meter (on output module 12) ispeaking around the +3 level.

Group Mix SwitchThis switch activates circuitry that sums all output mixes andassigns the summed signal to the Monitor B output. This out-put is stereo when stereo signals are present. This signal is postfader.

Headphone JackAllows for connection of headphones via a 1/4" TRS plug.There are two headphone jacks: one on master module B, andone underneath the armrest on the right front corner of the con-sole.

Headphone Level ControlControls the output level of both headphone jacks.

High Pass Filter SwitchThis switch inserts the High Pass Filter into the output signal.Unlike the 100Hz HPF on the inputs, the output HPF isadjustable via the HPF frequency control.


100 Hz High Pass Filter (Input)Reduces all Input signal low frequency content at a 12db peroctave rate referenced to 100Hz (-3db point).

InsertAll LM inputs and outputs have insert loops which facilitatethe patching of external processing equipment into the input oroutput signal. All LM inserts are pre EQ.

On the inputs, signal is always present at the Insert Send con-nection and the loop is complete when the proper connector isplugged into the Insert Return. The Insert Return can also beused as a line input when by-passing the preamp is desired.

On the outputs, the loop is controlled by the Insert On switch.Depressing this switch inserts the loop into the output signal.Since this a true insert, if an incomplete loop exists, depressingthe switch will mute the output.

Input/Output PFL IndicatorsThese LEDs indicate what type of signal (input or output) isPFL’d at any given time.

LM

APPENDIX B

CENTURY SERIES

Input Fader Mix SwitchThis switch activates circuitry that sums all input signals andassigns the summed signal to the Monitor A output. This signalis post fader.

Lamp Dim ControlControls the brightness of any 12 volt lighting devices attachedto the XLR connectors on the light bar.

LINE SwitchSelects the input signal source between the Balanced XLRMicrophone Input connector and the Balanced Line Input 1/4"TRS connector.

Line InputThis jack accepts balanced and unbalanced line level inputsand delivers it into the associated input channel.

Microphone InputThis connector accepts balanced microphone inputs for theassociated input channel.

Microphone OutputThis connector is in parallel with the Balanced Mic In connec-tor and allows easy connection of the monitor board to theFOH console.

Mix SendsEvery LM console has twelve (12) send controls. Each LMmodel deals with these twelve controls differently:

LM-12 • Each of the twelve knobs determine the amount ofsignal sent to each of the twelve outputs.

LM-8+4 • The first eight controls are dual concentric and theydetermine the amount of signal sent to the first eight stereooutputs. The center knob controls level while the outer knob isa PAN control. The last four knobs adjust the level of signalsent to outputs 9-12.

LM-20 • The first eight controls are dual concentric and theydetermine the amount of signal sent to the first sixteen outputs(1a/1b . . 8a/8b). The last four knobs adjust the level of signalsent to outputs 9-12.

Monitor A/B These are stereo local monitor outputs. Level is controlled viathe Monitor Level control and the signal is found on balancedoutput connectors (two per monitor) on the rear of the mastersection. Each Monitor can be muted with the Monitor Muteswitch. See - Input Fader Mix and Group Mix for more infor-mation.

MUTE Switch with LEDOn all inputs and outputs where this switch is present, depress-ing it will mute all sends. This switch does not affect the PFLswitch or the Peak and Signal Present LED indicators, TheLED illuminates when the channel is muted either from theswitch or via the scene mute system.

Oscillator OnSwitches on the internal (or external if connected) oscillatorwhich is fixed at 1kHz . The oscillator only operates when theTalkback system is engaged.

Oscillator / Pink Noise InThis connector accepts a balanced or unbalanced signal froman oscillator or pink noise generator. This signal is assignablevia the Talkback assignment switches. The external source isswitched in via the Oscillator On switch. The internal 1kHzoscillator is defeated when a plug inserted.

Output Insert - See InsertOutput EQ - See Equalizer Controls (Output)

PAD SwitchIntroduces a -15 dB drop to the mic input signal.



PFL IndicatorThis LED illuminates when the signal on meter 12 is a PFL orAFL signal

Phantom Power SwitchTurns on 48V Phantom Power as required by certain micro-phones for proper operation. This switch delivers +48V onlywhen the Phantom Power Master Switch is engaged.

Phantom Master Switch w/LEDSwitches +48V phantom power on and off for the entire con-sole.

Power IndicatorsShows the status of the four voltages used by the console.

Polarity Reverse SwitchElectrically inverts the polarity of associated signal.

PRE Switch Toggles mix sends (in groups of four) between Post and theinternally selected Pre state. See the Internal Settings section ofthe Technical Appendix.

PFL SwitchSamples the channel’s signal pre-fader and allows for monitor-ing within the master section of the console. This signal is notaffected by the Mute Switch. When depressed, the signal levelcan be seen on the output 12 meter, and heard via the mixer’sheadphone or local monitor output. When this PFL Switch isdepressed, the channel PEAK LED indicator illuminates at alower intensity. When used as a status indicator of switch posi-tion, the Peak LED indicating circuit remains fully operationby illuminating at a much higher intensity than its use as a PFLstatus indicator. Input PFL always takes priority over outputPFL.

LM

APPENDIX B

CENTURY SERIES

Return 1/2These connectors accept a balanced signal which is deliveredto the return master controls on the master section

Return Level ControlsAdjusts the level of return signals 1 and 2 in the output. Thesesignals come from the Master Section. The center knob adjustslevel while the outer knob adjusts panning within the stereoimage. See Returns 1 & 2 on the Master Section description formore information.

Return Master Level ControlsControls the final return signal level available to the outputs.


Scene Mute MastersThese four switches turn the four scene mutes on and off forthe entire console.

Scene Mute Safe SwitchDisables any selected scene mute assignments. An associatedgreen LED indicates the channel is in a safe state.

Signal Present LEDThis green LED constantly displays level activity of theinput/output channel by varying in intensity.

Sub Input ControlsAdjusts the level of cross-mix in the output from mono outputs11 and 12. The center knob adjusts level while the outer knobadjusts panning within the stereo image.

Sub 11/12 Post SwitchSwitches the subgroup between pre and post fader.

Sub 11/12 On SwitchSwitches the subgroup send on and off.

Talkback Master On/OffSwitches the internal Talkback system on and off

TB Enable SwitchInjects the talkback signal from the master section into the theassociated output.

Talkback Level ControlAdjusts the final level of all Talkback signals.

Talkback Mic InputAllows for connection of a gooseneck or other XLR typemicrophone to the Talkback system.

LOCATION DESCRIPTION SCHEMATIC # DWG # REV #

LM 12 (MONO) INPUT MODULE LM 12 INPUT CONNECTOR 1 76D1753 03

LM 12 INPUT MAIN 2 76D1812 01

LM 20 / 8+4 INPUT MODULE LM 20 / 8+4 INPUTCONNECTOR 3 76D1753 03

LM 20 / 8+4 INPUT MAIN 4 76D1830 01

MONO OUTPUT GROUP MODULE LM MONO OUTPUTGROUP CONNECTOR 5 76D1824 02

"(LM 12 Groups 1-10, LM 8+4 & LM 20 Groups 9&10)" LM MONO GROUP MAIN 6 76D1823 02

STEREO / DUAL MONO OUTPUT GROUP MODULE LM DUAL MONO / STEREOGROUP CONNECTOR (1 OF 2) 7 76D1832 02

(LM 20 & LM 8+4 Groups 1-8) LM DUAL MONO / STEREOGROUP CONNECTOR (2 OF 2) 8 76D1832 02

LM 8+4 STEREOGROUP MAIN (1 OF 2) 9 76D1831 02

LM 8+4 STEREOGROUP MAIN (2 OF 2) 10 76D1831 02

LM 20 DUAL MONOGROUP MAIN (1 OF 2) 11 76D1955 01

LM 20 DUAL MONOGROUP MAIN (2 OF 2) 12 76D1955 01

MASTER A OUTPUT MODULE MASTER A CONNECTOR PCB 13 76D1826 01MASTER A MAIN PCB 14 76D1825 01

MASTER B OUTPUT MODULE MASTER B CONNECTOR PCB 15 76D1829 01MASTER B MAIN PCB 16 76D1828 01

RIBBON CABLE PIN OUT DIAGRAMS RIBBON PIN OUTS 17 n/a n/a

LMAppendix C

Schematics

APPENDIX C

LM Owners ManualCopyright © 1997 Crest Audio Inc.

v. 2.3 11/3/97 - D7000002

Crest Audio Inc.100 Eisenhower Dr., Paramus NJ 07652 USA

TEL: 201.909.8700 FAX: 201.909.8744http://www.crestaudio.com

Printed in USA

*D7000002*

Documents

Century Series LM Owner's Manual