CREST CPX 2600 User Manual

owner’s manual

CPX power amplifier

S E R I E S

CPX

CPX 900
CPX 1500
CPX 2600

20 23

26

16

A

6

29

32

SIG

PWR

GCL

TM

(dB)

20 23

26

16

B

6

29

32

PWR

SIG

GCL

TM

(dB)

CPX 2600

POWER AMPLIFIER

ON

POWER

1

Save the carton and packing materi­als! Should you ever need to ship

the unit, use only the original factory
packing.

For replacement packaging, call Crest
Audio’s Customer Service Department
directly.

2

Read all documentation before
operating your equipment. Retain

all documentation for future reference.

3

Follow all instructions printed on
unit chassis for proper opera-

tion.

4

Never hold a power switch or cir­cuit breaker in the on-position, if

it won’t stay there by itself!

5

Do not use the unit if the electri­cal power cord is frayed or bro-

ken.

The 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.

6

Always operate the unit with the
AC ground wire connected to the

electrical system ground.

Precautions should be taken so that
the means of grounding of a piece of
equipment is not defeated.

7

Damage caused by connection to
improper AC voltage is not cov-

ered by any warranty. Mains voltage

must be correct and the same as that
printed on the rear of the unit.

8

Do not ground any hot (red) terminal.

Never connect a hot

(red) output to

ground or to another hot (red) output!

9

Power down and disconnect units
from mains voltage before making

connections.

10

Do not drive the inputs with a
signal level greater than that

required to enable equipment to
reach full output.

Do not run the output of any ampli­fier channel back into another
channel’s input.

Do not parallel- or series-con­nect an amplifier output with any
other amplifier output.

Crest Audio is not responsible for
damage to loudspeakers for any rea­son.

Do not connect the inputs or out­puts of amplifiers to any other
voltage source: such as a battery,

mains source, or power supply,
regardless of whether the amplifier
is turned on or off.

Connecting amplifier outputs to
oscilloscopes or other test equip­ment while the amplifier is in
bridged mono mode may damage
both the amplifier and test equip­ment!

Do not spill water or other liquids
into or on the unit, or operate the
unit while standing in liquid.

Do not block fan intake or
exhaust ports.

Do not operate equipment on a
surface or in an environment
which may impede the normal
flow of air around the unit: such

as a bed, rug, weathersheet, car­pet, or completely enclosed rack.

If the unit is used in an extreme­ly dusty or smoky environment:

the unit should be periodically
“blown free” of foreign matter.

Do not use the unit near stoves,
heat registers, radiators, or other
heat producing devices.

The power cord of equipment
should be unplugged from the out­let when left unused for a long peri­od of time.

Service Information

Do not remove the cover!

Removing the cover will expose you
to potentially dangerous voltages.
There are no user serviceable parts
inside.

Equipment should be serviced
by qualified service personnel
when:

A. The power supply cord or the plug has

been damaged.

B. The equipment has been exposed to

rain.

C. The equipment does not appear to

operate normally, or exhibits a marked
change in performance.

D. The equipment has been dropped, or

the enclosure damaged.

To obtain service:

contact your nearest Crest Audio
Service Center, Distributor, Dealer,
or Crest Audio at 201.909.8700

USA

or visit www.crestaudio.com for
additional information.

email: techserve

@crestaudio.com

important precautions

1
2

3

4

5

6

introduction

p.3

installation

p.5

unpacking
mounting
cooling and ventilation
powering
maintenance

features overview

p.11

front panel
rear panel

application details

p.23

installations
bridged
GCL

connections

p.27

input
output

Specifications

p.31

wire gauge charts

p.32, 33

contents

CPX Owner’s manual

p. 1

p. 2

introduction

1

CPX owner’s manual

p. 3

introduction

1

welcome

Congratulations on your purchase of a new CPX Series power amplifier, and
thank you for your confidence in Crest Audio products. You are among the grow­ing number of audio professionals who have made Crest Audio one of the world’s
leading suppliers of professional and commercial/industrial audio systems.

For your safety, please read the Important Precautions section before installing
and operating the amplifier. The Crest Audio CPX Series amplifiers are designed
for high operating efficiency and accurate sonic performance across the full audio
bandwidth, even under stressful conditions.

CPX series amplifiers feature a 2-way crossover and sub-sonic (low-cut) filter for
each channel. Crossover frequencies are fixed at 150 Hz, allowing subwoofers to
be driven at extremely high sound pressure levels, and the filters cut at 40 Hz to
prevent low-end rumble. Using proven technology gained through years of ampli­fier design, this unit takes advantage of rugged TO-3P output devices mounted
on massive aluminum extrusions and dissipates heat via an extremely quiet and
effective 2-speed fan. CPX amplifiers employ mammoth toroidal power trans­formers and offer impressive specifications and features not found on similarly
priced competitive units.

These amps are designed to drive a 2-ohm load per channel, thus achieving awe­some performance levels into 4 ohms in BRIDGE mode. CPX amplifiers are
ruggedly constructed, rack-mountable pieces of gear with superb patching capa­bility, allowing superior flexibility in application.

Front panel features include calibrated, detented gain (dB) controls and LED indi­cators for power (PWR), signal presence (SIG), and GCL (Gain Comparator
Limiter) activation on each channel, as well as a rocker mains POWER switch.

The back panel contains an IEC connector for the mains power cord, a mains cir­cuit breaker with reset, and the critical cooling fan opening. This opening should
have an adequate supply of cool air and should never be blocked or restricted.
Also on the back panel are the input and output sections, including an input bar­rier strip for permanent installations. Each channel input section includes a combo
XLR / ¼" phone jack connector, THRU/LOW out and HIGH out ¼" jacks, and acti­vation switches for the LOW CUT filter and crossover (150 Hz XOVER). Channel
output sections feature dual shock-proof binding posts and 4-conductor Speakon
connectors. An additional 4-conductor Speakon connector allows BRIDGE mode
output.

p. 4

CPX owner’s manual

installation

2

p. 5

installation

2

unpacking

mounting

cooling and
ventilation

maintenance

what to do with the shipping carton

proper rack-mounting technique

keeping the amplifier cooled

routine maintenance practices

CPX owner’s manual

p. 6

installation

2

unpacking

Please inspect the amplifier carefully immediately after unpacking. If
you find any damage, notify your supplier/dealer immediately. Only the
shipper may file a damage claim with the carrier for damage incurred
during shipping. Be sure to save the carton and all packing materials
for the carrier’s inspection.

If the packing materials are in good condition, please save them.

If you ever need to ship the unit anywhere without mounting it in a rack,
you should take advantage of the original factory packing materials in
order to avoid unnecessary damage.

For replacement pack­aging, call Crest Audio’s
Customer Service
Department directly.

see—service and support

2

p. 7

installation

mounting

All CPX Series amplifiers mount in standard 19-inch racks and occupy two rack
spaces. Use of rear supports is highly recommended in all mobile and touring
sound systems.

front width 19"/ 483mm

CPX Front panel

CPX rear panel

rear width 17"/ 432mm

front

height

3.47"/

88 mm

front

height

3.47"/
88mm

depth16"

CPX side view

20 23

26

16

A

6

29

32

SIG

PWR

GCL

(dB)

TM

20 23

26

16

B

6

29

32

PWR

SIG

GCL

TM

(dB)

CPX 2600

ON

POWER AMPLIFIER

POWER

MOUNT IN RACK ONLY - INSTALLER SUR

SUPPORT DE MONTAGE SEULEMENT

BREAKER

WARNING:

ELECTRIC SHOCK DO NOT EXPOSE THIS EQUIPMENT
TO RAIN OR MOISTURE.

15

AVIS:

A
M
P

CAUTION

TO REDUCE THE RISK OF FIRE OR

RISQUE DE CHOC ELECTRIQUE-NE PAS OUVRIR.

CHANNEL B CHANNEL A

BRIDGE

BRIDGE

-

CHANNEL B CHANNEL A

+-+

OUTPUT

BRIDGE

OUT STEREO/

IN BRIDGE

TM

GCL

OUT ENABLE /

IN DEFEAT

THRU

LOW OUTHIGH OUT

CHANNEL A INPUT

LOW CUT

150 Hz
X OVER

BAL. LOW Z

LOW CUT

150 Hz
X OVER

CHANNEL B INPUT

HIGH Z

+

A

-

GND

-

B

+

p. 8

installation

2

Make certain that there
is enough space
around the front and
rear of the amplifier to
allow the heated air to
escape. When mount­ing in a rack, try to
avoid using doors or
covers on the front and
rear of the enclosure;
the exhaust air must
not be impeded

suggestion

In racks with closed
backs allow at least
one standard-rack­space opening for
every four amps.

INSTALLATION

CPX professional power amplifiers are designed for durability in com­mercial installations and provide the quality performance required in
studio and home applications. They are 2-rack-space units of 16" (406
mm) depth designed to mount in a standard 19" rack. Rear mounting
ears are provided for additional support. The minimum rack depth
required from the mounting surface is 17" (432 mm) to allow adequate
connector clearance.

cooling and ventilation

CPX amplifiers use a forced air cooling system to maintain a low, even
operating temperature.

Air is drawn in by a DC fan on the rear panel, flows through the cool­ing fins and then exhausts through the front panel vent.

Heatsink temperature is monitored and controls the variable speed
fan. Fan speed increases only as required, keeping fan noise to a min­imum.

If the heatsink surpasses it’s maximum allowed temperature, the ther­mal protection circuit will activate and open the output relays allowing
the amplifier to cool to a safe temperature. Thermal protect activation
only occurs under extreme thermal conditions and is not part of nor­mal operation.

CPX owner’s manual

p. 9

installation

2

Basic setup

Rack mount the amplifier in the location where it is to be used, remembering to
allow for adequate access and cooling space. Make all the connections to the
proper INPUT connectors on the desired channel. Select the proper mode con­figuration (STEREO or BRIDGE). Connect speakers to the proper OUTPUT con­nectors, reviewing carefully the impedance and phase considerations. With the
POWER switch OFF, connect the IEC cord to the amplifier and then to a suitable
electrical outlet to allow proper current draw. With both channel gain (dB) controls
at their fully counterclockwise (-8) settings, turn the POWER switch to ON, and
slowly raise the gain controls to desired settings. Please carefully review this
manual. It covers all this information in greater detail.

maintenance

CPX amplifiers require no routine maintenance other than checking the cooling
fans to make sure they’re unblocked and working.

If the amplifier is used in an extremely dusty or smoky environment , the unit
should be periodically “ blown free “ ( using compressed air ) of any foreign mat­ter that may have built up inside the unit.

Users will not need to make any adjustments to the amplifier during it’s lifetime.
There are no user-serviceable parts or adjustments that require opening the
amplifier.