Crest audio LM OWNER'S MANUAL
CENTURY SERIES
LM
OWNER'S MANUAL
Congratulations on your purchase of a Century Series console. All of us at Crest Audio in Paramus, New
Jersey, USA, support your decision, knowing your console contains the finest combination of design and
manufacture in the industry.
While your new Century Series console is one of the most feature-packed available, great effort has been
put into making it simple to operate.
This manual explains the functions of your new console, how they operate and how they relate to each
other. If properly cared for, your new console will provide you with trouble-free, sonically accurate mixing
clear 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 USA
TEL 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: 201.909.8744
http://www.crestaudio.com
Printed in USA
TABLE OF CONTENTS
Feature Overview 2
LM
A brief description of the LM design, features and functions.
System Connections 3
LM
Contains diagrams illustrating conventional system connections.
Wiring Conventions 5
LM
Contains diagrams indicating how connectors for Crest consoles are wired.
Power Supply 6
LM
A description of the rack-mountable Century Series consoles power supply.
Power Connections 7
LM
A description of Crest console power connections.
Console Cooling 7
LM
A brief description of the dual-fan cooling setup.
LM-12 Input Module 8
LM
Profiles the LM-12 input module. The module is illustrated and described.
LM-20 (LM-8+4) Input Module 10
LM
Profiles the LM-20 (LM-8+4) input module. The module is illustrated and described.
LM-12 Output Module 13
LM
Profiles the LM-12 ouput module. The module is illustrated and described.
LM 8+4 Output Module 15
LM
Profiles the LM-8+4 output module. The module is illustrated and described.
LM-20 Output Module 17
LM
Profiles the LM-20 ouput module. The module is illustrated and described.
Master Module A 19
LM
Profiles the LM A-Master module. The module is illustrated and described.
Master Module B 21
LM
Profiles the LM B-Master module. The module is illustrated and described.
Technical Information Appendix A
LM
Includes dimensions, specifications, console access details,
user options, console block diagram, and rear panel layout.
Glossary Appendix B
LM
The specific details of console operation are described here, alphabetically.
Schematics Appendix C
LM
This appendix lists available LM console & power supply schematics.
PAGE 1
LM
Feature Overview
The Century Series was designed to have all the features and
functions demanded by the modern music professional. The
engineers at Crest Audio have delivered the finest combination
of function and sonic accuracy in an affordable intuitive console. The features listed below are common to all Century
Series LM Consoles.
• SSM/PMI High quality devices on balanced
microphone/line inputs and on all outputs for uncompro-
mised audio quality and reliability. All IC’s within the audio
path are socket mounted for easy upgrade or service.
• The signal path is completely free of electrolytic capacitors and all internal audio connections are gold plated.
• Passive microphone splitters on every microphone input.
• 48 Volt switchable phantom power on all microphone
inputs.
• Optional transformers available on all microphone inputs
and primary outputs.
• Dynamic Signal Present and multiple-sample- point Peak
indicator LED’s are used on all input sections of the console
as 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 monitored in mono.
• Standard frame sizes include 32, 40, 44, 52 and 64 module
positions. Any frame size may be ordered short loaded for later
expansion.
• The three banks of four rotary send controls each have an
associated Pre switch. This switch can be internally selected to
operate as pre EQ or pre Fader; this selection applies to all
three Pre switches on the module.
• Each of the twelve send controls can be internally selected
to operate in one of three modes: follow its associated Pre
switch, always Pre or always Post.
CENTURY SERIES
• 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, Insert
switch, Talkback enable, Dim, Peak & dynamic Signal Present
LEDs, local Mute and PFL.
• Return level controls provide signal from Returns 1 and 2
found on the Master section. The Sub Input controls deliver
signal from outputs 11 and 12 which are selectable pre or post
fader. This feature allows mixes 11 and 12 to be cross-mixed
to all other outputs.
• Comprehensive Talkback section allows access to all primary console outputs. External signals can also be assigned
into the talkback system.
• The basis of every Century console is signal integrity.
From the input preamplifier's impressive EIN of -129 dBu, to
completely balanced primary busing, the Century LM delivers
one of the cleanest signals available at any cost. This signal
purity comes from using only the highest quality components
in its innovative design. All inputs and outputs are electronically balanced, the primary inputs and outputs have the option of
transformer isolation.
• UL/CE-approved external power supply over-designed
with ample current reserves. For the ultimate in fail-safe reliability, a back-up power supply can be linked to the primary
supply with only an inexpensive jumper cable. External
switching is not needed.
• Mute system on input channels is designed to mute both pre
and post fader signals. When muted, PFL circuitry and, Peak
and Dynamic Signal Present LED indicators remain fully operational. This is a feature not available on many consoles at any
cost.
• Four scene (A-D) mute system
• The EQ section includes an EQ IN switch with LED and a
100Hz 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 control with generous overlap. The high and low frequency bands
are selectable between Peaking and Shelving via internal
jumpers.
PAGE 2
CENTURY SERIES LM
LIVE MONITOR CONSOLE
System Connections
The console is the nerve center of a sound system and controls
most of the variables within a system. Proper connection and
component relationships are vital to assure accurate operation
and results. The following diagrams illustrate conventional system connections.
In
Signal Processors
Out
Insert Send/Return Connection
Front of House
Console
DIR OUT
DIR OUT
DIR OUT
DIR OUT
INSERT SEND
INSERT SEND
INSERT SEND
INSERT SEND
BAL INSERT RTN
BAL INSERT RTN
BAL INSERT RTN
BAL INSERT RTN
BAL LINE IN
BAL LINE IN
BAL LINE IN
BAL LINE IN
BAL MIC IN
BAL MIC IN
BAL MIC IN
BAL MIC IN
From
Stage
Microphones
Microphone Splitting
PAGE 3
LM
CENTURY SERIES
Floor Wedge Connection
Clip/Limit
Signal
Temp/DC
Active
-6
-6
-10
-3
-10
-3
-15
-15
-1
-1
-30
-30
-80
0dB
-80
0dB
Ch A
Ch B
Clip/Limit
Signal
Temp/DC
Active
-6
-6
-10
-3
-10
-3
-15
-15
-1
-1
-30
-30
-80
0dB
-80
0dB
Ch A
Ch B
Receivers for
In-Ear Monitors
6001 Professional Power Amplifier
6001 Professional Power Amplifier
Stereo In-Ear Monitor Connection
PAGE 4
Transmitters for
In-Ear Monitors
CENTURY SERIES
LM
Wiring Conventions
Since the same connectors are used throughout the professional audio industry, it is important to know how the connectors for
Crest’s Century Series are wired. The wiring is as follows.
INPUT XLR
1
3
2
PIN 1
PIN 3
PIN 2
PIN 1 = GROUND
PIN 2 = POSITIVE
PIN 3 = NEGATIVE
OUTPUT XLR
PIN 2
PIN 3
PIN 1
TIP - POSITIVE
RING - NEGATIVE
SLEEVE - GROUND
OUTPUT
Output Plug Polarities
INPUT
Input Plug Polarities
TIP - POSITIVE
RING - NEGATIVE
SLEEVE - GROUND
TIP - SEND
RING - RETURN
SLEEVE - GROUND
INSERT
Insert send & Insert return Polarities
PAGE 5
LM
CENTURY SERIES
Power Supply
Century 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 determines
which of the two supplies should be used.
Model
LM
Press to Reset
ON
Supply Model XCVA04
Frame Size 24,32
C O N S O L E S
Power Supply
CAUTION
RISK OF ELECTRIC SHOCK
AVIS : RISQUE DE CHOC ÉLECTRIQUE—NE PAS OUVRIR
ÉLECTRIQUE, NE PLACEZ PAS CET APPAREIL SOUS LA PLUIE OU Á
DO NOT OPEN
EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE.
ATTENTION! POUR ÉVITER LE RISQUE D'INCENDIE OU DE CHOC
L'HUMIDITÉ
Designed & manufactured in the USA by:
A division of Crest Audio Inc.
100 Eisenhower Dr.
Paramus, New Jersey 07652 USA
1
2
3
4
5
7
6
Pin 1 +24V
Pin 2 +20V
Pin 3 Analog
Pin 4 Analog
Pin 5 Digital
Pin 6 +48V
Pin 7 -20V
POWER OUT
WARNING TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK DO NOT
POWER OUT
Supply Identification
The type of power supply can be identified by the model number shown on the back of the chassis and panel label.
Power Requirements
The Century Series power supplies have certain electrical
requirements to operate properly. If possible the power supply
should be connected to a dedicated circuit. Should any other
appliance on the same circuit draw enough current to overload
the circuit, the breaker or fuse will trip causing loss of power
to the console. Note the maximum current draw specifications
at right. Be sure that the circuit to which you connect the supply can handle the draw.
The power switch on the supply front panel is also a circuit
breaker, there is no power fuse. Should the supply ever shut
down, or trip at start up, simply push the switch to the off position and then on again.
Ground Linking
Safety Considerations - Each new power supply is shipped
with the AC third wire ground connected to the console chassis
ground. The connection is made at the rear of the power supply
unit. This is necessary for safety reasons so that exposed metal
parts are grounded. In the event of a live conductor making
contact with the console chassis or the power supply chassis
then the current will flow to ground without a safety hazard
arising. Note that when the console is disconnected from the
power supply the chassis ground connection to AC third wire
ground is broken and safety protection is lost. For uninterruptible grounding, in a fixed installation for example, make a connection 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 third
wire ground which would otherwise create a hum-loop.
Supply Model XCVA06
Frame Size 40,44,52,64
+20V
+48V
4A
MAXIMUM AC IN:
XCVA04: 415 WATTS
XCVA06: 825 WATTS
Model XCVA04
± 20V @ 4
+ 24V @ 4
+ 48V @ 1
+ 24V @ 6
S/N
± 20V @ 6
Model XCVA06
CONSOLE
GROUND
-20V
CHASSIS
GROUND
+24V
Twin Supply Operation
When twin supplies are in use for automatic back-up, then the
ground links on both supplies should be fitted. In a situation
where the safety ground to the console chassis has been connected and the ground path via the power supply is causing a
hum-loop, then disconnect the ground links on BOTH power
supplies.
Console and Power Supply Grounding
Console chassis ground is electrically connected to audio
ground, pin 1 of XLR connectors and 1/4" sockets and to the
terminal ‘CONSOLE GROUND’ at the rear of the power supply. The AC third wire connection in the power supply cable
connects the metal chassis of the power supply to safety
ground. This connection should never be disturbed. Hazardous
voltages exist inside the power supply which require the case
to be grounded. When rack-mounted, the power supply ground
may transfer to the rack case thru the front fixing screws,
though this connection is not reliable. When a console is configured within a complete sound system the grounding requirements may call for the ground link to be disconnected. This is
permissible only when an alternative ground path has been
provided. If in doubt seek the
advice of an experienced electrical engineer.
Power Supply Model
XCVA04
XCVA06
Model XCPS-40
S/N
±20V @ 4
+24V @ 4
+48V @ 1A
+24V @ 6A
±20V @ 6A
Model
XCVA06
Max Current Draw 120V/230V
7A/4A
9A/5A
PAGE 6
CENTURY SERIES
LM
Power Connections
The connections to and from the power supply vary depending on your specific configuration. Multiple power supplies can be
daisy-chained to provide fail-safe protection in the event of a supply failure. When two or more supplies are used, they may be
connected 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.
To Console
CAUTION
RISK OF ELECTRIC SHOCK
DO NOT OPEN
AVIS : RISQUE DE CHOC ÉLECTRIQUE—NE PAS OUVRIR
WARNING TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK DO NOT
EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE.
ATTENTION! POUR ÉVITER LE RISQUE D'INCENDIE OU DE CHOC
ÉLECTRIQUE, NE PLACEZ PAS CET APPAREIL SOUS LA PLUIE OU Á
L'HUMIDITÉ
Designed & manufactured in the USA by:
A division of Crest Audio Inc.
100 Eisenhower Dr.
Paramus, New Jersey 07652 USA
Model XCVA04
S/N
± 20V @ 4
+ 24V @ 4
+ 48V @ 1
+ 24V @ 6
± 20V @ 6
Model XCVA06
CONSOLE
GROUND
CHASSIS
GROUND
MAXIMUM AC IN:
XCVA04: 415 WATTS
XCVA06: 825 WATTS
To AC Mains
1
2
4
5
6
7
Pin 1 +24V
Pin 2 +20V
Pin 3 Analog
Pin 4 Analog
Pin 5 Digital
Pin 6 +48V
Pin 7 -20V
POWER OUT
3
POWER OUT
Interface Cable
POWER OUT
1
2
3
4
5
6
7
Pin 1 +24V
Pin 2 +20V
Pin 3 Analog
Pin 4 Analog
Pin 5 Digital
Pin 6 +48V
Pin 7 -20V
POWER OUT
Console Cooling
A 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 distributed
through the chassis via a “vortex pan”, then proceeds up through the console modules, where the heated air exits the console
chassis.
CAUTION
RISK OF ELECTRIC SHOCK
DO NOT OPEN
AVIS : RISQUE DE CHOC ÉLECTRIQUE—NE PAS OUVRIR
WARNING TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK DO NOT
EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE.
ATTENTION! POUR ÉVITER LE RISQUE D'INCENDIE OU DE CHOC
ÉLECTRIQUE, NE PLACEZ PAS CET APPAREIL SOUS LA PLUIE OU Á
L'HUMIDITÉ
Designed & manufactured in the USA by:
A division of Crest Audio Inc.
100 Eisenhower Dr.
Paramus, New Jersey 07652 USA
Model XCVA04
S/N
± 20V @ 4
+ 24V @ 4
+ 48V @ 1
+ 24V @ 6
± 20V @ 6
Model XCVA06
CONSOLE
GROUND
CHASSIS
GROUND
MAXIMUM AC IN:
XCVA04: 415 WATTS
XCVA06: 825 WATTS
To AC Mains
Once the console is powered up, cooling fans remain on. A rear panel switch permits the fans to be set at low, medium or high
speeds.
There are no filters to change or clean. As with any console, use in dusty/unclean environments should be avoided.
PAGE 7
LM
3
CENTURY SERIES
7
8
2
9
1
10
+48V
10
20
63060
LINE
PAD
GAIN
100
ø
4
HF
10
3
2K
20K
1.5
HM
3
250
100
1K
400
100
2
2
1
2
1
2
2
2
1
2
2
400
150
40
PRE
5
46
3
1
0
5
4
3
0
5
4
3
0
5
46
3
1
0
PRE
5
4
3
1
0
5
46
3
0
5
46
3
1
0
5
46
3
1
0
8K
2K
3
800
EQ IN
10
6
10
6
10
10
6
10
10
10
10
6
LM
1
LF
6
1
7
8
9
2
7
8
9
3
7
8
9
4
7
8
9
5
7
8
9
6
7
8
9
7
7
8
9
8
7
8
9
0
46
3
2
1
0
4
3
2
1
0
46
3
2
1
0
46
3
2
1
0
46
3
2
1
0
46
3
2
1
0
46
3
2
1
0
46
3
2
1
0
46
3
2
1
0
PEAK
SIG
A
B
C
D
SAFE
SCENE
MUTE
SELECT
5
4
7
8
9
10
PRE
5
5
6
7
8
9
10
5
6
7
8
9
10
5
7
7
8
9
10
5
8
7
8
9
10
PRE
5
9
7
8
9
10
5
10
7
8
9
10
5
11
7
8
9
10
5
12
7
8
9
10
DIR OUT
INSRT SND
MUTE
PFL
BAL INSRT RTN
BAL LINE IN
LIFT
0
5
10
20
30
40
PIN 1
BAL MIC IN
BAL MIC OUT
PRE
5
9
46
3
7
2
8
LM-12 INPUT MODULE
The LM-12 input module is the primary input control for the LM12 monitor console. It differs from the LM-20 input module only
in the mix send section.
48V Phantom Power Switch
Turns on 48V Phantom Power as required by certain microphones
for proper operation.
LINE Switch
Selects between the Balanced XLR Microphone Input connector
and the Balanced Line Input 1/4" TRS connector.
PAD Switch
Introduces a -15 dB cut to the mic input signal.
GAIN Control
Adjusts input gain for proper signal level.
100Hz High Pass Switch
Reduces all low frequency content at a 12db per octave rate referenced to 100Hz (-3db point).
Polarity Reverse Switch
Inverts the polarity of both the microphone and line inputs.
Four-Band Sweep Equalizer Controls
There are two knobs for each of the four bands. The inner knob
controls the boost or cut; while the outer knob controls the center
frequency. These center frequencies are printed on the chassis
around the outer knob.
EQ IN Switch
Inserts the EQ section into the input channel signal. An associated
LED illuminates when the switch is down.
PRE Switch 1-4
Toggles mix sends 1-4 between Post and the internally selected
Pre state.
Mix Sends 1-4
Adjusts signal level sent to output mixes 1-4
PRE Switch 5-8
Toggles mix sends 5-8 between Post and the internally selected
Pre state.
Mix Sends 5-8
Adjusts signal level sent to output mixes 5-8
PRE Switch 9-12
Toggles mix sends 9-12 between Post and the internally selected
Pre state.
Mix Sends 9-12
Adjusts signal level sent to output mixes 9-12
MUTE Switch with LED
Mutes the channel and all sends except the insert send. This
switch does not affect the PFL switch or the Peak and Signal
Present LED indicators, The LED illuminates when the channel is
muted either from the local mute switch or the scene mute system.
PAGE 8
CENTURY SERIES
LM
PFL Switch
Samples the channel’s signal pre-fader and allows for monitoring within the master section of the console. This signal is not
affected by the Mute Switch. When depressed, the signal level
can be seen on the output 12 meter, and heard via the mixer’s
headphone or local monitor output. When this PFL Switch is
depressed, the channel PEAK LED indicator illuminates at a
lower intensity. When used as a status indicator of switch position, the Peak LED indicating circuit remains fully operational
by illuminating at a much higher intensity than when indicating PFL status.
PEAK LED Indicator
Illuminates RED when any of the points monitored come within 3db of the clipping point. Signal is sampled after the input
preamplifier stage, after the EQ section, and after the fader.
This LED also serves as a PFL ON indicator, but at a much
lower intensity than when it is used to indicate clipping.
SIGNAL PRESENT LED
This green LED constantly displays level activity of the input
channel by varying in intensity.
100mm Fader
Used for control of all outputs of the channel except those
sends selected pre fader. (The Insert Output level is not affected by the fader position.)
Rear Panel Connections
Direct Out
This 1/4-inch TRS jack carries the direct output signal (post
fader & post mute) from the associated input channel.
Insert Send
This 1/4-inch TRS jack carries the send signal of the insert
loop to the external effect or signal processor.
Balanced Insert Return
This 1/4-inch TRS jack accepts the return signal of the insert
loop from the external effect or signal processor back into the
console.
Balanced Line In
This 1/4-inch TRS jack accepts balanced and unbalanced line
level inputs and delivers it into the associated input channel.
Lift Pin 1
This ground lift switch may be used to isolate pin1 of the mic
XLR from console ground.
Unpressed = pin 1 grounded
Pressed = pin 1 lifted
Balanced Mic In
This XLR connector accepts balanced microphone inputs for
the associated input channel.
Scene Mute Assignments
Assign the input channel to any of the four scene mute groups.
Scene mute combines with the module’s local mute button, and
actuates the local mute LED.
Scene Mute Safe Switch
Disables any selected scene mute assignments. An associated
green LED indicates that the channel is in a safe state.
Balanced Mic Out
This XLR connector is in parallel with the Balanced Mic In
connector and allows easy connection of the monitor board to
the FOH console.
PAGE 9
LM
7
3
CENTURY SERIES
1
0
5
46
3
1
0
PRE
5
4
3
1
0
5
46
3
1
0
5
46
3
1
0
5
46
3
1
0
PRE
5
46
3
2
1
0
5
46
3
2
1
0
5
46
3
2
1
0
5
46
3
2
1
0
PEAK
SIG
SAFE
10
10
6
10
10
10
10
10
10
10
10
MUTE
PFL
8
9
4
7
8
9
LM-20 (LM-8+4) INPUT MODULE
This module serves as the input module for LM-20 and the nowdiscontinued LM-8+4. The only difference between the two is
the factory default settings on the dual concentric sends.For the
LM-20 the sends are set for level/level operation. For an LM8+4 the sends are set for level/pan operation.
5
7
8
9
6
7
8
9
7
7
8
9
8
7
8
9
48V Phantom Power Switch
Turns on 48V Phantom Power as required by certain microphones for proper operation.
LINE Switch
Selects between the Balanced XLR Microphone Input connector
and the Balanced Line Input 1/4" TRS connector.
PAD Switch
Introduces a -15 dB cut to the mic input signal.
GAIN Control
Adjusts input gain for proper signal level.
100Hz High Pass Switch
9
7
8
9
10
7
8
9
11
7
8
9
12
7
8
9
DIR OUT
INSRT SND
BAL INSRT RTN
BAL LINE IN
Reduces all low frequency content at a 12db per octave rate referenced to 100Hz (-3db point).
Polarity Reverse Switch
Inverts the polarity of both the microphone and line inputs.
Four-Band Sweep Equalizer Controls
There are two knobs for each of the four bands. The inner knob
controls the boost or cut; while the outer knob controls the center frequency. These center frequencies are printed on the chassis around the outer knob.
EQ IN Switch
Inserts the EQ section into the input channel signal. An associated LED illuminates when the switch is down.
PRE Switch 1-4
Toggles mix sends 1-4 between Post and the internally selected
Pre state.
Mix Sends 1-4
Adjusts signal level sent to stereo output mixes 1-4 or mono
LIFT
0
5
10
PIN 1
BAL MIC IN
BAL MIC OUT
mixes 1a through 4b.
PRE Switch 5-8
Toggles mix sends 5-8 between Post and the internally selected
Pre state.
Mix Sends 5-8
Adjusts signal level sent to stereo output mixes 5-8 or mono
20
mixes 5a through 8b.
PRE Switch 9-12
30
40
Toggles mix sends 9-12 between Post and the internally selected
Pre state.
Mix Sends 9-12
Adjusts signal level sent to stereo output mixes 9-12 or mono
mixes 9a through 12b.
2
+48V
10
20
63060
LINE
PAD
GAIN
2
2
100
ø
2
4
HF
10
3
2K
1.5
1K
400
400
250
100
150
100
40
46
3
2
1
0
4
3
2
1
0
4
3
2
1
0
46
3
2
1
0
4
3
2
1
0
46
3
2
1
0
46
3
2
1
0
46
3
2
1
0
46
3
2
5
5
5
5
5
5
5
5
5
PRE
PRE
PRE
20K
3
EQ IN
10
6
10
6
10
10
6
10
10
10
10
HM
3
8K
1
2K
800
7
9
7
9
7
9
7
9
7
9
7
9
7
9
7
9
7
8
6
LM
LF
6
1
8
2
8
3
8
4
8
5
8
6
8
7
8
8
8
9
2
2
A
B
C
D
SCENE
MUTE
SELECT
PAGE 10
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