Harman-Kardon 234, 223, 223XL, 234XL User Manual

2-Way, 3-Way

Operation

Manual

4-Way Crossovers

223/223XL - 234/234XL

®

WARNING

FOR YOUR PROTECTION, PLEASE READ THE FOLLOWING:

WATER AND MOISTURE: Appliance should not be used near water (e.g. near a

bathtub, washbowl, kitchen sink, laundry tub, in a wet basement, or near a swimming
pool, etc). Care should be taken so that objects do not fall and liquids are not spilled
into the enclosure through openings.

POWER SOURCES: The appliance should be connected to a power supply only of
the type described in the operating instructions or as marked on the appliance.

GROUNDING OR POLARIZATION: Precautions should be taken so that the ground­ing or polarization means of an appliance is not defeated.

POWER CORD PROTECTION: Power supply cords should be routed so that they are
not likely to be walked on or pinched by items placed upon or against them, paying
particular attention to cords at plugs, convenience receptacles, and the point where
they exit from the appliance.

SERVICING: To reduce the risk of fire or electric shock, the user should not attempt to
service the appliance beyond that described in the operating instructions. All other
servicing should be referred to qualified service personnel.

FOR UNITS EQUIPPED WITH EXTERNALLYACCESSIBLE FUSE RECEPTACLE:

Replace fuse with same type and rating only.

SAFETY INSTRUCTIONS

NOTICE FOR CUSTOMERS IF YOUR UNIT IS EQUIPPED WITH APOWER
CORD.

WARNING: THIS APPLIANCE MUST BE EARTHED.

The cores in the mains lead are coloured in accordance with the following code:

GREEN and YELLOW - Earth BLUE - Neutral BROWN - Live

As colours of the cores in the mains lead of this appliance may not correspond
with the coloured markings identifying the terminals in your plug, proceed as fol­lows:

• The core which is coloured green and yellow must be connected to the
terminal in the plug marked with the letter E, or with the earth symbol, or
coloured green, or green and yellow.

• The core which is coloured blue must be connected to the terminal
marked N or coloured black.

• The core which is coloured brown must be connected to the terminal
marked L or coloured red.

This equipment may require the use of a different line cord, attachment plug, or
both, depending on the available power source at installation. If the attachment
plug needs to be changed, refer servicing to qualified service personnel who
should refer to the table below. The green/yellow wire shall be connected
directly to the unit's chassis.

WARNING: If the ground is defeated, certain fault conditions in the unit or in the
system to which it is connected can result in full line voltage between chassis
and earth ground. Severe injury or death can then result if the chassis and
earth ground are touched simultaneously.

U.K. MAINS PLUG WARNING

A moulded mains plug that has been cut off from the cord is unsafe. Discard the
mains plug at a suitable disposal facility. NEVER UNDER ANY CIRCUM-

STANCES SHOULD YOU INSERT A DAMAGED OR CUT MAINS PLUG INTO
A 13 AMP POWER SOCKET. Do not use the mains plug without the fuse cover

in place. Replacement fuse covers can be obtained from your local retailer.
Replacement fuses are 13 amps and MUST be ASTAapproved to BS1362.

ELECTROMAGNETIC COMPATIBILITY

This unit conforms to the Product Specifications noted on the Declaration of
Conformity. Operation is subject to the following two conditions:

• this device may not cause harmful interference, and

• this device must accept any interference received, including interference
that may cause undesired operation.

Operation of this unit within significant electromagnetic fields should be avoided.
Use only shielded interconnecting cables.

The symbols shown above are internationally accepted symbols that warn of
potential hazards with electrical products. The lightning flash with arrowpoint in
an equilateral triangle means that there are dangerous voltages present within
the unit. The exclamation point in an equilateral triangle indicates that it is nec­essary for the user to refer to the owner’s manual.

These symbols warn that there are no user serviceable parts inside the unit.
Do not open the unit. Do not attempt to service the unit yourself. Refer all ser­vicing to qualified personnel. Opening the chassis for any reason will void the
manufacturer’s warranty. Do not get the unit wet. If liquid is spilled on the unit,
shut it off immediately and take it to a dealer for service. Disconnect the unit
during storms to prevent damage.

CAUTION

RISK OF ELECTRIC SHOCK

DO NOT OPEN

ATTENTION:
WARNING:

SHOCK DO NOT EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE

RISQUE DE CHOC ELECTRIQUE - NE PAS OUVRIR

TO REDUCE THE RISK OF FIRE OR ELECTRIC

CONDUCTOR

L
N
E

LIVE

NEUTRAL

EARTH GND

WIRE COLOR

Normal Alt

BROWN

BLUE

GREEN/YEL

BLACK
WHITE

GREEN

2-Way, 3-Way

1

8760 South Sandy Pkwy.

Sandy, Utah 84070

Phone: [phone]

Fax: [phone]

Int’l Fax: [phone]

Questions or comments?

E•mail us at: [e-mail]

or visit our World Wide Web home page at:

http://www.dbxpro.com

TABLE OF CONTENTS

WARRANTY....................................................................................................................2

INTRODUCTION .......................................................................................................................................................2

INSPECTION ...........................................................................................................................................................3

234/234XL FRONT PANEL OPERATION .............................................................................................................................3

223/223XL FRONT PANEL OPERATION .............................................................................................................................5

234/234XL-223/223XL REAR PANELOPERATIONS ...........................................................................................................6

234/234XL-223/223XLAUDIO CONNECTIONS ...................................................................................................................7

ELECTRICAL CONNECTIONS .............................................................................................................................................7

FEATURES ...........................................................................................................................................................................7

RACK MOUNTING, GROUNDING AND SAFETY ...............................................................................................................8

TROUBLESHOOTING ..........................................................................................................................................................9

234/234XL-223/223XL SPECIFICATIONS ..........................................................................................................................11

DECLARATION OF CONFORMITY ....................................................................................................................................12

4-Way Crossovers

223/223XL - 234/234XL

®

A Harman International Company

WARRANTY

INTRODUCTION

Congratulations on your purchase of the dbx 223/223XL or 234/234XL
crossover. We are confident you will find this crossover to be the finest
product of its kind in this price range. We have taken care to include all of
the features you need to make your system sound its best. Some of the
features common to both the 234/234XL and the 223/223XL crossovers
are:

• back panel switches for selecting the operating mode of the
crossover.

• back panel switches indicating the selected range of crossover fre­quencies. Both of these features have LED indicators on the front
panel so you can see at a glance which mode the unit is in.

• low frequency summed output designed specifically for mono sub­woofer applications.

• phase invert switches on all outputs.

• individual level controls on every output.

We are sure you will agree that these crossovers are built to provide
extremely high quality frequency division for all applications.

2

1. The warranty registration card that accompanies this product must be
mailed within 30 days after purchase date to validate this warranty.
Proof-of-purchase is considered to be the burden of the consumer.

2. dbx warrants this product, when bought and used solely within the
U.S., to be free from defects in materials and workmanship under nor­mal use and service.

3. dbx liability under this warranty is limited to repairing or, at our discre­tion, replacing defective materials that show evidence of defect, provid­ed the product is returned to dbx WITH RETURN AUTHORIZATION
from the factory, where all parts and labor will be covered up to a peri­od of two years. AReturn Authorization number must be obtained from
dbx by telephone. The company shall not be liable for any consequen­tial damage as a result of the product's use in any circuit or assembly.

4. dbx reserves the right to make changes in design or make additions to
or improvements upon this product without incurring any obligation to
install the same additions or improvements on products previously
manufactured.

5. The foregoing is in lieu of all other warranties, expressed or implied,
and dbx neither assumes nor authorizes any person to assume on its
behalf any obligation or liability in connection with the sale of this prod­uct. In no event shall dbx or its dealers be liable for special or conse­quential damages or from any delay in the performance of this warran­ty due to causes beyond their control.

223/223XL - 234/234XL

2-Way, 3-Way

4-Way Crossovers

®

2-Way, 3-Way

INSPECTION

Before going any further, you should take time to fill out your warranty
registration card and inspect the contents of the shipping carton. Inside
both the 223/223XL and 234/234XL boxes you should find the following:

• either the dbx model 223, 223XL, 234, or the 234XL crossover.

• operation manual (you are reading it!)

• 4 rack screws and washers

• power cord.

The contents of this manual are subject to change at any time without
notice.

3

STEREO 2-WAY MODE

In 2-way stereo mode the controls are marked BELOW the horizontal blue line.
Channel One and Channel Two functions are identical in the stereo mode. Front panel controls not described in
this section are not active in stereo 2-way operation.

[1] & [7] INPUT GAIN Controls the INPUT level with +/- 12 dB of gain.
[13] & [20] LOW CUT Switch for selecting the 40 Hz high pass filter. An LED indicates the

selection.
[2] & [8] LOW/MID* Selects crossover point between the LOW and HIGH outputs.
[14] & [21] X10 LED Indicates that the LOW/HIGH crossover frequency range is 450 Hz to

9.6 kHz.
[4] & [10] LOW OUTPUT Controls the Low frequency output level with a range of -∞ to +6 dB.
[15] & [22] PHASE INVERT Switch for reversing the polarity on the Low Output. An LED indicates

that the phase is inverted.

[6] & [12] H

IGH OUTPUT Controls the High frequency output with a range of -∞ to +6 dB.

[17] & [24] PHASE INVERT Switch for reversing the polarity on the High Output. An LED indicates

that the phase is inverted.

[19] STEREO LED indicating stereo mode operation.
* although this control is labeled as “LOW/MID”, it operates as the crossover frequency control between low and

high frequencies in stereo 2-way operation.

dbx 234/234XL Front Panel

1 2 3 4 5 6 7 8 9 10 11 12

13 14 15 16 17 1819 20 21 22 23 24

Note: There are no front panel differences between the 234 and the 234XL. Therefore the

234XL is shown below, representing both the 234 and the 234XL.

4-Way Crossovers

223/223XL - 234/234XL

CHANNEL ONE CHANNEL TWO

0

-6 +6

-12

dB

GAIN
INPUT

INPUT

240

1.4k

350

140

70 680

45

Hz

XOVER FREQ
LOW/LOW-MID

LOW/MID

700

x10

960

450

LOW-MID/HIGH-MID

40 Hz 40 Hz

+12

LOW CUT

LOW CUT

2.4k

Hz

XOVER FREQ

MID/HIGH

-10

3.5k

-30

6.8k

9.6k

-

dB

GAIN

LOW OUTPUT

LOW OUTPUT

-10

-30

0

INV INV INV INV INV INV

+6

-

dB

GAIN

LOW-MID OUTPUT

MID OUTPUT HIGH OUTPUT INPUT LOW CUT LOW/MID

-10

-30

0

+6

0

+6

-

dB

GAIN

MONO

STEREO

0

-6 +6

-12

dB

GAIN

240

1.4k

350

140

70 680

700

45

Hz

XOVER FREQ

x10

960

450

+12

-10

2.4k

3.5k

-30

6.8k

9.6k

-

Hz

dB

XOVER FREQ

GAIN

HIGH-MID/HIGH

MID/HIGH LOW OUTPUT

-30

0

+6

-

HIGH-MID OUTPUT HIGH OUTPUT

MID OUTPUT HIGH OUTPUT

-10

dB

GAIN

-10

-30

0

+6

0

+6

-

dB

GAIN

®

2-Way, 3-Way

4

1 2 3 4 5 6 7 8 9 10 11 12

13 14 15 16 17 1819 20 21 22 23 24

®

STEREO 3-WAY MODE

In 3-way stereo operation the controls are marked BELOW the horizontal blue line.
Channel One and Channel Two functions are identical in the stereo mode. LEDs are disabled for controls which are non­functional in this mode.

[1] & [7] INPUT GAIN Controls the INPUT level with +/- 12 dB of gain.
[13] & [20] LOW CUT Switch for selecting the 40 Hz high pass filter. An LED indicates the selec-

tion.
[2] & [8] LOW/MID Selects crossover point between LOW and MID frequencies.
[14] & [21] X10 LED Indicates that the LOW/MID crossover frequency range is 450 Hz to 9.6 kHz.
[3] & [9] MID/HIGH Selects crossover point between MID and HIGH frequencies.
[4] & [10] LOW OUTPUT Controls the Low Frequency output level with a range of -∞ to +6 dB.
[15] & [22] PHASE INVERT Switch for reversing the polarity on the Low Output. An LED indicates the

selection.
[5] & [11] MID OUTPUT Controls the Mid Frequency output with a range of -∞ to +6 dB.
[16] & [23] PHASE INVERT Switch for reversing the polarity on the Mid Output. An LED indicates the

selection.
[6] & [12] HIGH OUTPUT Controls the High Frequency output with a range of -∞ to +6 dB.
[17] & [24] PHASE INVERT Switch for reversing the polarity on the High output. An LED indicates the

selection.
[19] STEREO LED indicating stereo mode operation.

MONO 4 -WAY MODE

In 4-way mono operation the controls are marked ABOVE the horizontal blue line. Front panel controls not described in
this section are not active in mono 4-way mode. LEDs are disabled for controls which are non-functional in mono 4-way
mode.

[1] INPUT GAIN Controls the input level with +/- 12 dB of gain.

[13] L

OW CUT Switch for selecting the 40 Hz high pass filter. An LED indicates the

selection.
[2] LOW/LOW-MID Selects crossover point between LOW and LOW-MID frequencies.
[14] X10 LED Indicates that the LOW/LOW-MID crossover frequency range is 450 Hz to

9.6 kHz.
[3] LOW-MID/HIGH-MID Selects the crossover point between LOW-MID and HIGH-MID frequencies.
[9] HIGH-MID/HIGH Selects the crossover point between HIGH-MID and HIGH frequencies.
[4] LOW OUTPUT Controls the LOW frequency output level with a range of -∞ to +6 dB.
[15] PHASE INVERT Switch for reversing the polarity on the Low Output. An LED indicates the

selection.
[5] LOW-MID OUTPUT Controls the LOW-MID frequency output level with a range of -∞ to +6 dB.
[16] PHASE INVERT Switch for reversing the polarity on the Low-Mid Output. An LED indicates

the selection.
[11] HIGH-MID OUTPUT Controls the HIGH-MID frequency output level with a range of -∞ to +6 dB.
[23] PHASE INVERT Switch for reversing the polarity on the High-Mid Output. An LED indicates

the selection.
[12] H

IGH OUTPUT Controls the HIGH frequency output level with a range of -∞ to +6 dB.

[24] PHASE INVERT Switch for reversing the polarity on the High Output. An LED indicates

the selection.
[18] M

ONO LED indicating mono mode operation.

223/223XL - 234/234XL

4-Way Crossovers

CHANNEL ONE CHANNEL TWO

0

-6 +6

-12

dB

GAIN
INPUT

INPUT

240

1.4k

350

140

70 680

45

Hz

XOVER FREQ
LOW/LOW-MID

LOW/MID

700

x10

960

450

LOW-MID/HIGH-MID

40 Hz 40 Hz

+12

LOW CUT

LOW CUT

2.4k

Hz

XOVER FREQ

MID/HIGH

-10

3.5k

-30

6.8k

9.6k

-

dB

GAIN

LOW OUTPUT

LOW OUTPUT

-10

-30

0

INV INV INV INV INV INV

+6

-

dB

GAIN

LOW-MID OUTPUT

MID OUTPUT HIGH OUTPUT INPUT LOW CUT LOW/MID

-10

-30

0

+6

0

+6

-

dB

GAIN

MONO

STEREO

0

-6 +6

-12

dB

GAIN

240

350

140

1.4k

70 680

700

45

Hz

XOVER FREQ

x10

960

450

+12

-10

2.4k

3.5k

-30

6.8k

9.6k

-

Hz

dB

XOVER FREQ

GAIN

HIGH-MID/HIGH

MID/HIGH LOW OUTPUT

-30

0

+6

-

HIGH-MID OUTPUT HIGH OUTPUT

MID OUTPUT HIGH OUTPUT

-10

0

+6

dB

GAIN

-10

-30

0

+6

-

dB

GAIN

2-Way, 3-Way

5

1 2 3 4 5 6 7 8

9 10 11 12 1314 15 16 17 18

®

STEREO 2-WAY MODE

In 2-way stereo mode the controls are marked BELOW the horizontal blue line.
Channel One and Channel Two functions are identical in the stereo mode. LEDs are disabled for controls
which are non-functional in this mode.

[1] & [5] I

NPUT GAIN Controls the INPUT level with +/- 12 dB of gain.

[9] & [15] LOW CUT Switch for selecting the 40 Hz high pass filter. An LED indicates

the selection.
[2] & [6] LOW/HIGH Selects crossover point between the LOW and HIGH outputs.
[10] & [16] X10 LED Indicates that the LOW/HIGH crossover frequency range is 450

Hz to 9.6 kHz.
[3] & [7] LOW OUTPUT Controls the Low Frequency output level with a range of -∞ to +6

dB.
[11] & [17] PHASE INVERT Switch for reversing the polarity on the Low Output. An LED indi-

cates the selection.
[4] & [8] H

IGH OUTPUT Controls the High Frequency output with a range of -∞ to +6 dB.

[12] & [18] PHASE INVERT Switch for reversing the polarity on the High Output. An LED indi-

cates the selection.
[14] STEREO LED indicating stereo mode operation.

MONO 3 -WAY MODE

In 3-way mono operation the controls are marked ABOVE the horizontal blue line. Front panel controls not
described in this section are not active in mono 3-way mode. LEDs are disabled for controls which are non­functional in this mode.

[1] INPUT GAIN Controls the input level with +/- 12 dB of gain.

[9] L

OW CUT Switch for selecting the 40 Hz high pass filter. An LED indicates

the selection.
[2] LOW/MID Selects crossover point between LOW and MID frequencies.
[10] X10 LED Indicates that the LOW/MID crossover range is 450 Hz to 9.6 kHz.
[6] MID/HIGH Selects the crossover point between MID and HIGH frequencies.
[16] X10 LED Indicates that the MID/HIGH crossover frequency range is 450 Hz

to 9.6 kHz
[3] LOW OUTPUT Controls the LOW frequency output level with a range of -∞ to +6

dB.
[11] PHASE INVERT Switch for reversing the polarity on the Low Output. An LED indi-

cates that the phase is reversed.
[7] MID OUTPUT Controls the MID frequency output level with a range of -∞ to +6

dB.
[17] PHASE INVERT Switch for reversing the polarity on the Mid Output. An LED indi-

cates that the phase is reversed.
[8] HIGH OUTPUT Controls the HIGH frequency output level with a range of -∞ to +6

dB.
[18] PHASE INVERT Switch for reversing the polarity on the High Output. An LED indi-

cates that the phase is reversed.
[13] MONO LED indicating mono mode operation.

Note: There are no front panel differences between the 223 and the 223XL. Therefore the

223XL is shown below, representing both the 223 and the 223XL.

dbx 223/223XL Front Panel

4-Way Crossovers

223/223XL - 234/234XL

240

45

Hz

XOVER FREQ

LOW/MID

LOW/HIGH

350

-30

680

x10

960

-10

-

dB

GAIN

LOW OUTPUT

LOW OUTPUT HIGH OUTPUT

0

-6 +6

140

70

40 Hz

-12

+12

dB

GAIN
INPUT

LOW CUT

INPUT

LOW CUT

-10

-30

0

+6

0

INV INV INV INV

+6

-

dB

GAIN

MONO

STEREO

0

-6 +6

-12

dB

INPUT LOW CUT

CHANNEL TWOCHANNEL ONE

140

70

40 Hz

+12

240

45

Hz

XOVER FREQGAIN

MID/HIGH

LOW/HIGH

-10

350

-30

680

x10

960

-

dB

GAIN

MID OUTPUT

LOW OUTPUT

-10

-30

-

dB

GAIN

HIGH OUTPUT

HIGH OUTPUT

0

+6

0

+6

234/234XL-223/223XL REAR

PANEL OPERATIONS

MODE SWITCHES

234XL REAR PANEL

234 REAR PANEL

The mode switches on the back panel of the unit are used to select one
of the three modes of operation in the 234/234XL and one of two modes
of operation in the 223/223XL. There could be disastrous consequences
if the crossover were improperly setup or the switches were mistakenly
pushed during the regular operation of a sound system. Therefore great
care should be taken when setting these switches. There is a mode dia­gram on the back panel to help you understand at a glance how this is
done. The following steps should be taken in setting up your system:

• Know the loudspeaker manufacturer’s requirements regarding the
amplification needs of your particular speaker system. Follow the
maunfacturer’s guidelines carefully, as dbx is not responsible for dam­age relating to improper setup or implementation of the 234/234XL­223/223XL.

• Without any audio or power connections in place, use the back panel
switches on the crossover to set it to the proper mode of operation;
either stereo 2-way, stereo 3-way, or mono 4-way for the 234/234XL,
or stereo 2-way or mono 3-way for the 223/223XL.

• Use the literature that came with your speaker system to properly set
up the mode of operation and crossover frequencies to the manufac­turer’s specifications.

• There is one of the four possible mode button combinations for the
234/234XL which is marked “not valid”. Be sure you have not select­ed this combination as the 234/234XL will not operate correctly in this
mode.

When you are certain that the proper selections have been made, com­plete the steps described below and in the “234/234XL-223/223XL Audio
Connections” section on page 7.

6

223/223XL - 234/234XL

2-Way, 3-Way

4-Way Crossovers

15 WATTS

100V 50/60Hz

120V 60Hz

®

PROFESSIONAL PRODUCTS

A HARMAN INTERNATIONAL
COMPANY
SALT LAKE CITY, UTAH
MADE IN USA
MODEL 234

STEREO 3-WAY
STEREO 2-WAY

MONO 4-WAY

HIGH

HIGH

CHANNEL TWO

MID

NOT USEDHIGH

HIGH-MID

LOW
LOW INPUTLOW/HIGH

NOT USED

INPUT

x 1
x 10

XOVER FREQ XOVER FREQ

NOT USED

MODE

STEREO 3-WAY
STEREO 2-WAY
NOT VALID

MONO 4-WAY

®

LF SUM

LOW SUM
LOW SUM

NORMAL
SUMMED

ONLY

CHANNEL ONE

MID

HIGHLOW/MID
HIGH NOT USED LOW/HIGHLOW/LF SUM INPUT

NOT USEDNOT USED

LOW-MID

LOW/LF SUM

LOW

LOW/MID

x 1
x 10

LOW/LOW-MID

INPUT

INPUT

2-Way, 3-Way

223XL REAR PANEL

223 REAR PANEL

234/234XL-223/223XL
AUDIO CONNECTIONS

ELECTRICAL CONNECTIONS

On the back panel of the 234/234XL, there are markings to help you con­nect the source devices and amplifiers to your crossover. To operate the
234/234XL in stereo 3-way operation, follow the top row of markings hori­zontally along the length of the 234/234XL. For stereo 2-way operation of
the 234/234XL, use the second row of markings directly above the con­nectors. For mono 4-way operation of the 234/234XL, use the markings
directly below the connectors. The connectors not used in the selected
mode are marked “not used”. This designation applies only to that mode
of operation.

The 223/223XL is marked in a similar way: for stereo 2-way operation use
the markings above the connectors. To operate the 223/223XL in mono 3­way mode use the markings below the connectors. The connectors which
are not used in the selected mode are marked “not used”. This designa­tion applies only to that mode of operation.

• Before connecting anything to the crossover, make sure it is not con­nected to any power source.

• Be sure that the source device (equalizer, compressor, mixing console,
etc.) for the 234/234XL-223/223XL is turned off. Connect the output(s) of
the source device to the inputs of the crossover, following the rear panel
markings carefully.

• Make sure that the amplifiers which will be used to drive your speaker
system are turned off. Using the back panel markings as a guide, use
high quality cables to connect the amplifiers to the appropriate outputs
of the 234/234XL-223/223XL.

Ensure that your 223/223XL/234/234XL crossover conforms to the AC
power specifications in your area, by checking the marked voltage spec
on the rear of the unit. Never plug the incorrect voltage into your

7

4-Way Crossovers

223/223XL - 234/234XL

15 WATTS

100V 50/60Hz

120V 60Hz

®

PROFESSIONAL PRODUCTS

A HARMAN INTERNATIONAL
COMPANY
SALT LAKE CITY, UTAH
MADE IN USA
MODEL 223

CHANNEL TWO MODE

HIGH

LOW

HIGH

MID

STEREO

MONO

STEREO
MONO

LF SUM

LOW SUM

NORMAL
SUMMED

NOT USED

INPUT

x 1
x 10

NOT USED

HIGH

NOT USED

CHANNEL ONE

LOW/LF SUM

LOW

LOW/HIGH

XOVER FREQXOVER FREQ

LOW/MIDMID/HIGH

INPUTLOW/HIGH

x 1
x 10

INPUT

®

223/223XL - 234/234XL

FEATURES

X10 OPERATION

POLARITY SWITCH

LOW FREQUENCY SUMMING

crossover, as this may cause severe damage not covered under the dbx
warranty. Connect the power cord to the crossover first, then to a power
source that is properly grounded. Never lift the ground as a shock hazard
may result.

After you have safely plugged in the crossover, turn on the source
device(s). Turn the amplifiers’ outputs all the way down (-∞) and turn on
the amplifiers. All of the elements of your sound system should now be
on, and the amplifiers should be turned all the way down. Turn the source
device to its nominal operating level, sending a nominal (average) level to
the 234/234XL-223/223XL. Slowly turn up the amplifiers’ outputs until you
can hear signal at a comfortable volume. Make adjustments as you
desire.

If you are using your system in stereo 2-way or 3-way mode, the needed
crossover frequency may be higher than 960 Hz, making it necessary to
set the x10 switch to the active position. This changes the range of oper­ation of the frequency selector from 45-960 Hz to 450 Hz to 9.6 kHz. All
other frequency selectors remain the same. When using the X10 switch,
ALWAYS ensure that the amplifiers feeding all speaker systems are
turned off or that the input gain controls on the power amplifiers are
turned down before changing the setting of the X10 switch. Not doing so
may send a spurious signal to the outputs of the crossover when the X10
switch is engaged, and may damage speaker systems which are pow­ered at the time of the spurious signal.

Every output is equipped with a polarity (Ø) reverse switch on the front
panel. When speakers are not “in phase”, the frequency response of the
system is compromised, particularly in the low frequencies. Out of phase
signals can also cause “comb-filtering” in the high frequencies. The polar­ity switch is extremely useful for fine tuning your sound system for peak
performance. An LED is activated when the output polarity is reversed.

The other feature accessed on the back panel is “low frequency sum­ming”. This is useful with systems that utilize mono subwoofers.
Activating the LF sum switch “sums” the low frequencies of both the left
and right inputs. The sum is sent to channel one’s low output marked “LF
SUM”, while channel two’s low output is not used, and channel two’s
phase invert led is disabled, indicating it is not operational in “LF Sum”
mode. The summed low frequencies represent all the low frequencies of
both the left and right inputs, and since lows are generally non-directional

8

2-Way, 3-Way

4-Way Crossovers

®

2-Way, 3-Way

RACK MOUNTING, GROUNDING

AND

SAFETY

TROUBLESHOOTING

NO SOUND

ABNORMAL AUDIO OUTPUT

anyway, it will not detract from the true stereo picture of the source mate­rial.

We have provided 4 rack screws and washers for easy mounting in stan­dard audio racks. You should avoid mounting the unit near large power
transformers or motors. Route the AC cord away from audio lines and
plug it into a power source close by. If the power cord must cross over
audio lines, you should take care to have them cross at 90 degree
angles.

The input and output connectors are balanced/unbalanced 1/4” TRS- type
connectors. The tip of the plug is wired as hot (+), the ring is wired as
cold (-), and the sleeve is wired as the ground or shield.

The 234/234XL-223/223XL crossovers have differentially balanced input
and output circuits. Balanced wiring is recommended, even with unbal­anced source devices, especially when running long paths. Twin-conduc­tor, shielded cable is more reliable since it does not depend on the shield
wire itself to complete the signal connection. Using twin conductor cable,
a broken shield may only result in a slight increase in noise or hum due
to the lack of shielding. You may also use unbalanced cables to connect
to and from the crossover.

If there appears to be no power:

• Check that either the stereo or mono LED on the front panel of the
234/234XL-223/223XL is lit.

• Check that the power cord is seated properly in the back panel of the
crossover and that it is plugged into an active AC power source.

If there appears to be power, but no audible signal:

• Confirm that active audio lines are connected to the crossover’s
inputs and outputs.

• Check that both the input and output gain controls are advanced suffi­ciently.

• Check to make sure that you have turned up the amplifiers’ outputs.

• Ensure that the proper mode for your setup has been selected via the
rear panel mode switches.

• Check the LF Sum switch.

• Check the x10 switch. This changes the range of the crossover fre­quency from 45 - 960 Hz to 450 Hz - 9.6 kHz.

9

4-Way Crossovers

223/223XL - 234/234XL

®

223/223XL - 234/234XL

• Check that a clean signal is being fed to the crossover.

• Confirm that the input wiring is correct.

• Check that the grounds of the audio signal path and the chassis and
power line of all units in the system are connected.

If you suspect that the hum is caused by a ground loop:

• Systematically remove and/or connect the audio grounds of the devices
in the signal path.

• Remember, for safety you must maintain connection to chassis ground.
Never lift a safety ground.

If you suspect the hum is not caused by a ground loop.

• Check the audio at an earlier stage in the audio chain.

• Low level equipment should be mounted away from power amplifiers to
avoid induction of this type of hum.

• Be certain that all audio wiring except for loudspeaker lines is well shield­ed, and that low level wiring is not run parallel to and/or in close proximi­ty to AC power wiring.

• Check the other equipment and the wiring to make certain that the signal
is not intermittent earlier in the chain.

• Check the integrity of all cables using a cable tester.

10

WEAK AND/OR DISTORTED AUDIO

HUM AND/OR BUZZ

INTERMITTENT AUDIO

2-Way, 3-Way

4-Way Crossovers

®

2-Way, 3-Way

dbx 234/234XL-223/223XL
S

PECIFICATIONS

11

INPUT:

Connectors: 1/4” TRS (223/234) or XLR (234/234XL)
Type: Electronically balanced/unbalanced, RF filtered
Impedance: Balanced > 50 kΩ, unbalanced > 25 kΩ
Max Input Level: +22 dBu typical, balanced or unbalanced
CMRR: >40 dB, typically > 55 dB at 1 kHz

OUTPUT (223/234):

Connectors: 1/4” TRS
Type: Impedance-balanced/unbalanced, RF filtered
Impedance: Balanced 200 Ω, unbalanced 100 Ω
Max Output Level: >+21 dBu balanced/unbalanced into 2 kΩ or greater

OUTPUT (223XL/234XL):

Connectors: XLR
Type: Electronically-balanced/unbalanced, RF filtered
Impedance: Balanced 60 Ω, unbalanced 30 Ω
Max Output Level: >+20 dBu balanced/unbalanced into 600Ω or greater

PERFORMANCE:

Bandwidth: 20 Hz to 20 kHz, +0/-0.5 dB
Frequency Response: < 3 Hz to > 90 kHz, +0/-3 dB
Signal-to-Noise: Ref: +4 dBu, 22 kHz measurement bandwidth

Stereo Mode: Mono Mode:

234/234XL: Low Output: > 94 dB > 94 dB

Low-Mid Output: > 94 dB
Mid Output: > 93 dB
High-Mid Output: > 92 dB
High Output: > 90 dB > 88 dB

223/223XL: Low Output: > 94 dB > 94 dB

Mid Output: > 93 dB
High Output: > 91 dB > 91 dB

Dynamic Range: > 106 dB, unweighted, any output
THD+Noise: < 0.004% at +4 dBu, 1 kHz

< 0.04% at +20 dBu, 1 kHz

Interchannel Crosstalk: < -80 dB, 20 Hz to 20 kHz

CROSSOVER FREQUENCIES:

234/234XL: Stereo Mode:

Low/High: 45 to 960 Hz or 450 Hz to 9.6 kHz (x10 setting)
Low/Mid: 45 to 960 Hz or 450 Hz to 9.6 kHz (x10 setting)
Mid/High: 450 Hz to 9.6 kHz

234/234XL: Mono Mode:

Low/Low-Mid: 45 to 960 Hz or 450 Hz to 9.6 kHz (x10 setting)
Low-Mid/High-Mid: 450 Hz to 9.6 kHz
High-Mid/High: 450 Hz to 9.6 kHz

223/223XL: Stereo Mode:

Low/High: 45 to 960 Hz or 450 Hz to 9.6 kHz (x10 setting)

223/223XL: Mono Mode:

Low/Mid: 45 to 960 Hz or 450 Hz to 9.6 kHz (x10 setting)
Mid/High: 45 to 960 Hz or 450 Hz to 9.6 kHz (x10 setting)

Filter Type: Linkwitz-Riley, 24 dB/octave, state-variable

FUNCTION SWITCHES:

Front Panel:

Low Cut: Activates 40 Hz Butterworth, 12 dB/octave high-pass

filter, one switch per channel.

Phase Invert: Inverts the phase at the output, one switch per output.

Rear Panel:

x10: Multiplies crossover frequency range by 10, one switch per channel.
Mode: Selects stereo/mono and 2/3/4-way operation.
LF Sum: Selects normal (stereo) or mono-summed low frequency operation.

INDICATORS:

Stereo Operation: Green LED
Mono Operation: Yellow LED
Low Cut: Red LED per channel
x10: Green LED per channel
Phase Invert: Red LED per output (3 per channel)

POWER SUPPLY:

Operating Voltage: 100 VAC 50/60 Hz, 120 VAC 60 Hz

230 VAC 50/60 Hz
Power Consumption: 15 Watts
Mains Connection: IEC 320 receptacle

PHYSICAL:

Dimensions: 1.75” H X 19” W X 6.9” D (4.4cm x 48.3cm x 17.5cm)
Weight: 234/234XL: 4.0 lbs. (1.8 kg) 223/223XL: 3.7 lbs. (1.7 kg)
Shipping Weight: 234/234XL: 5.8 lbs. (2.6 kg) 223/223XL: 5.4 lbs. (2.5 kg)

Note: Specifications subject to change.

4-Way Crossovers

223/223XL - 234/234XL

®

12

Manufacturer’s Name: dbx Professional Products
Manufacturer’s Address: 8760 S. Sandy Parkway

Sandy, Utah 84070, USA

declares that the product:

Product name: dbx223 and dbx234
Product option: None

conforms to the following Product Specifications:

Safety: EN 60065 (1993)

IEC65 (1985) with Amendments 1, 2, 3
CAN/CSA E65-94

EMC: EN 55013 (1990)

EN 55020 (1991)

Supplementary Information:
The product herewith complies with the requirements of the Low Voltage Directive 72/23/EEC and the

EMC Directive 89/336/EEC as amended by Directive 93/68/EEC.

dbx Professional Products
Vice-President of Engineering
8760 S. Sandy Parkways
Sandy, Utah 84070, USA
February 6, 1997

European Contact: Your local dbx Sales and Service Office or

Harman Music Group
8760 South Sandy Parkway
Sandy, Utah
84070 USA
[phone]
[phone]

DECLARATION OF CONFORMITY

223/223XL - 234/234XL

2-Way, 3-Way

4-Way Crossovers

2-Way, 3-Way

13

Manufacturer’s Name: dbx Professional Products
Manufacturer’s Address: 8760 S. Sandy Parkway

Sandy, Utah 84070, USA

declares that the product:

Product name: dbx223XL and dbx234XL
Product option: None

conforms to the following Product Specifications:

Safety: EN 60065 (1993)

IEC65 (1985) with Amendments 1, 2, 3
CAN/CSA E65-94

EMC: EN 55013 (1990)

EN 55020 (1991)

Supplementary Information:
The product herewith complies with the requirements of the Low Voltage Directive 72/23/EEC and the

EMC Directive 89/336/EEC as amended by Directive 93/68/EEC.

dbx Professional Products
Vice-President of Engineering
8760 S. Sandy Parkways
Sandy, Utah 84070, USA
March 9, 1999

European Contact: Your local dbx Sales and Service Office or

Harman Music Group
8760 South Sandy Parkway
Sandy, Utah
84070 USA
[phone]
[phone]

DECLARATION OF CONFORMITY

4-Way Crossovers

223/223XL - 234/234XL

®

8760 South Sandy Pkwy.

Sandy, Utah 84070

Phone: [phone]

Fax: [phone]

Int’l Fax: [phone]

Questions or comments?

E•mail us at: [e-mail]

or visit our World Wide Web home page at:

http://www.dbxpro.com

This manual is
dbx part number: 18-2155-C
03/19/99

A Harman International Company