Peavey 8002 User Manual

owner’s manual

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8002

Professional Power Amplifier

Status

Signal

ACL

8002 power amplifier

important precautions

Save the carton and packing materials!

1

Should you ever need to ship the unit,
use only the original factory packing.

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

Read all documentation before

2

operating your equipment. Retain all
documentation for future reference.

Follow all instructions printed on

3

unit chassis for proper operation.

Never hold a power switch in the

4

on-position, if it won’t stay there
by itself!

Do not use the unit if the electrical

5

power cord is frayed or broken.

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.

Always operate the unit with the

6

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

.

Damage caused by connection to

7

improper AC voltage is not covered
by any warranty.Mains voltage must be

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

Do not ground any hot (red) terminal.

8

Never connect a hot
ground or to another hot (red) output!

(red) output to

Do not run the output of any ampli-

¡

fier 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 out-

Ô

puts 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

ˆ

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.

Service Information

Do not remove the cover!

Removing the cover will expose you to
potentially dangerous voltages.There are
no user serviceable par ts 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 oper-

ate 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

or visit www.crestaudio.com for addi-
tional information.

email techserve

@crestaudio.com

This symbol is used to alert
the operator to follow important
procedures and precautions
detailed in documentation.

This symbol is used to warn operators
that uninsulated “dangerous voltages”
are present within the equipment enclosure
that may pose a risk of electric shock.

USA

Power down and disconnect units

9

from mains voltage before making
connections.

Do not drive the inputs with a sig-

0

nal level greater than that
required to enable equipment to
reach full output.

Do not use the unit near stoves,

¶

heat registers, radiators, or other
heat producing devices.

The power cord of equipment

ƒ

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

p. 1

table of contents

1

2

3

4

5

6

7

how to use this manual

p.2

introduction

p.3

installation

p.5

unpacking
mounting
cooling and ventilation
powering
maintenance

features overview

p.11

front panel
rear panel

operation modes

p.17

stereo
parallel
bridged

connections

p.21

input
output

safety

p.27

tourclass protection
precautions
user responsibility

service and support

p.33

support
contact us
registration

specifications

p.36

block diagram

p.37

wire gauge charts

p.38

a

b

c

contents

appendixes

p. 2

Pro II owner’s manual

how to use this manual

1

conventions

terms

official Crest Audio features and
each indicator or control on the amplifier will appear as: terms

actions

specific actions or selections the user can execute will appear as: actions

tasks

are broken down into steps 1

2
3

warnings

indicators

tips

see

see—refers to other sections of the manual containing

supplementary information on the current topic or a related issue

note

note—supplimentary feature information

Prefered methods.
Helpful hints.
Feature insights.

+

Procedures not to attempt.

Issues or hazards to keep
in mind when operating
the equipment.

a

What to look for on
the equipment display.

Alerts, indicators, or
prompts that may appear.

®

p. 3

introduction

1

welcome

Congratulations on your purchase of a new Pro II Series professional
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 Pro II Series is based
on the same advanced circuit topologies that have made Crest’s original
Professional Series amplifiers the choice of touring professionals world­wide. Pro II Series amplifiers are designed for high operating efficiency and
accurate sonic performance across the full audio bandwidth, even under
stressful conditions.

The Pro II Series heralds a major advance in amplifier design from Crest
Audio, providing the extreme reliability and hallmark sonic accuracy for
which Crest products are famous, in a rugged package but at only half the
weight of previous models of similar power.These dramatic weight savings
are made possible by PowerLok, a radical new power-supply technology
that provides significant performance and flexibility advances over conven­tional designs.PowerLok is Crest Audio's unique implementation of Power
Factor Correction, which allows current to be drawn throughout the
entire cycle of the

AC line-frequency, providing maximum output power,

while drawing significantly smaller peak currents from the

AC line.

Compared with an amplifier using a conventional power-supply, PowerLok
requires less peak power to produce identical output power, and because
PowerLok's current peaks are smaller, a Pro II amplifier can be serviced by
a lower-rated breaker than a conventional amplifier of similar wattage. See
separate literature for full details on the benefits of PowerLok technology.

In order to maintain strict quality assurance standards, all Crest Audio
power amplifiers are built in our state-of-the-art

USA manufacturing facili-

ty. Internal components are the finest available and key sub-assemblies are
pre-tested before final assembly. Each amplifier is “burned in” and thor­oughly tested

(using precision audio test equipment) before shipping. In

addition, all Pro II Series amplifiers incorporate Crest’s exclusive TourClass
protection features to safeguard both internal circuitry and connected
loudspeakers.

This proven combination of advanced design, quality construction, and
comprehensive circuit protection is your guarantee of fail-safe reliability.
You can depend on consistent, stable performance even when your Pro II
Series amplifier is subjected to punishing extremes in the most demanding
fixed or mobile sound reinforcement applications.

p. 4

p. 5

installation

2

unpacking

mounting

cooling and
ventilation

powering

maintenance

/

what to do with the shipping carton

/

proper rack-mounting technique

/

keeping the amplifier cooled

/

grounding the amplifier

/

required AC line voltages

/

routine maintenance practices

Pro II 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 back to Crest Audio or an authorized ser­vice center, you should use only the original factory packing.

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

see—service and support

+

p. 7

installation

2

mounting

All Pro II Series amplifiers mount in standard 19-inch racks.Four front-panel
mounting holes are provided on each amplifier. Rear mounting ears give addi­tional support, and use of rear supports is highly recommended in all mobile
and touring sound systems. Handles are fitted standard.

Ch A Ch B

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8002

Professional Power Amplifier

Status

Signal

ACL

front
height

5.25"/
133mm

front width 19"/483mm

8002 shown

8002 shown

35mm

rear width 17"/432mm (19” / 483mm to rack ear s)

depth 18"/457mm

rear
height

5.25"/
133mm

Pro II owner’s manual

p. 8

installation

2

To ensure optimum
cooling of the amplifier,
periodically clean its fan
filters. These are removable
without tools.

Make certain that there is
enough space around the
front of the amplifier
to allow the heated air to
escape. If the amplifier is
rack-mounted, do not use
doors or covers on the front
of the rack; the exhaust air
must not be impeded

In racks with closed backs:
for every four amplifiers,
allow at least one standard­rack-space opening in the
front of the rack.

a

cooling and ventilation

Pro II Series amplifiers use a twin-tunnel forced-air cooling system to main­tain a low, even operating temperature.

Drawn in by dual 105

CFM (cubic feet-per-minute) DC fans on the rear panel,

air flows through the cooling fins of the channel heat-sinks,dissipating power
transistor heat

—then exhausts through the front panel slots.

Heat sink temperature-sensing circuits control the “intelligent” variable­speed fans. Fan speed increases only as required by heat-sink temperatures

—

keeping fan noise to a minimum.

Under extreme thermal load, the fans will force a very large volume of air
through the heat sinks. If either heat-sink surpasses the maximum allowed
temperature, the sensing circuit will open the output relay, disconnecting the
load from that channel.

If the power supply overheats, another sensing circuit opens both channel
output relays, until it has cooled to a safe temperature.

p. 9

installation

2

powering

Unless otherwise specified when ordered, Pro II amplifiers shipped to cus­tomers are configured as follows:

North America 90–255

VAC

@

50–60Hz

Europe 180–255 VA C @50–60Hz

Asia 180 –255 VAC @50–60Hz

Australasia 180–255 VA C @50–60Hz

South America 90–255 VAC @50–60Hz

Japan 90–255 VA C @50–60Hz

maintenance

A Pro II Series amplifier requires no routine maintenance other than the
occasional cleaning or replacement of the fan intake filters on the rear of the
amplifier.

(This operation does not require any tools.) Filters must be kept

clear and clean to ensure proper ventilation through the unit.

If the amplifier is used in an extremely dusty or smoky environment, the fil­ter should be cleaned or changed frequently and the unit should be period­ically “blown free”

(using compressed air) of any foreign matter that may have

penetrated the filter.

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

Always turn off and dis­connect the amplifier from
mains voltage before mak­ing audio connections.

As an extra precaution, have
the attenuators turned down
during power-up.

a

Cover removal exposes
the risk of shock, so refer
all servicing to qualified
service technicians autho­rized by Crest Audio.

a

p. 10

p. 11

features overview

3

front panel

rear panel

/

location of connectors and controls

/

legend of panel symbols

Pro II owner’s manual

p. 12

features overview

3

Ch A Ch B

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ØdB

8002

Professional Power Amplifier

Status

Signal

ACL

8002 shown

1 2 3

8

4

7

5

6

p. 13

features overview

3

front panel

1

Rack Mounting Ears

Two front-panel mounting holes are provided on each mounting ear.

2

Rack Handles

3

Fan Outlet Grills

Pro II Series amplifiers are cooled by two,rear-mounted fans.Cool air
flows over the heat sinks and exhausts through the front grills. Make
sure these outlets remain clear to allow unrestricted airflow.

4

Signal LED

A variable-intensity LED that illuminates to indicate that a signal (above
a minimum threshold

) is present at the amplifier input, and that the sig-

nal is being amplified.

5

Input Attenuators

Two input attenuators adjust level for their respective amplifier chan­nels. In Bridged Mono mode, the channel A attenuator controls signal
level.

6

Status LED

A bi-color LED.When green, it indicates that AC power is connected
and the amplifier is turned on.When red,the channel is in

Protect mode

(speakers disconnected by output relay).

7

ACL LED

Illuminates at the clipping threshold. Continuous illumination also indi­cates that

ACL ACTIVE CLIP LIMITING protection circuitry is engaged.

8

AC Power Switch/Circuit Breaker

Pro II Series amplifiers have a front-panel combination AC switch/cir-
cuit breaker.

(No fuses are used.) If the switch shuts off during normal

use, push it back to the on-position once.If it will not stay on,the ampli­fier needs servicing.

note—all LEDs are one per channel

Never try to hold the
circuit breaker/power
switch in the on-position,
if it won’t stay there itself!

a

Pro II owner’s manual

p. 14

features overview

3

rear panel

1

Output Connectors

Pro II Series power amplifiers are supplied with both high-current five­way binding posts and Speakons installed. Binding posts: one pair per
channel. Speakons: one connector per channel, plus a third connector
configured for bridged-mono operation.

Connection to the binding posts can be made with bare wire or spade
lug terminations. Make connections to both the channel A and channel B
terminals for Stereo or Parallel mode, or a single connection across the
red

(hot) terminals only of channels A and B for Bridged Mono mode.

Using cables terminated with Speakon connectors, attach to both the
channel A and channel B connectors for Stereo or Parallel mode, or to
the Bridged mode connector/s for Bridged Mono mode.

see—operation modes

2

Mode Selection Switch

This recessed, three-position switch configures the amplifier for Stereo,
Parallel or Bridged Mono mode operation. Amplifiers are factory-config­ured for Stereo mode.

see—operation modes

Do not adjust the mode
selection switch while the
amplifier is turned-on.

a

rear panel legend

+

1

3-

2+

A

A

B

B

A

A

B

AB

A

GAIN

Ø

dBu

40x

20x

XLR Pin +

2 3

XLR Pin +

2 3

GAIN

Ø

dBu

40x

20x

A

B

B

A

+
+

+

B

A

A

B

input connection

XLR

connector polarity

TRS connector polarity

bridged mono mode

parallel mode

stereo mode

chassis ground lifted-position

chassis ground grounded-position

gain select

XLR pin 2/3 hot (+)

output connection

speakon output

channel A stereo/parallel

channel B stereo/parallel

bridged mono

five-way binding post

channel A stereo/parallel

bridged mono

channel B stereo/parallel

1

2

3

8

4

7

5

6

8002 shown

p. 15

features overview

3

rear panel

3

Female Balanced XLR Input Connectors

4

Male Balanced XLR Input Connectors

These connectors accept input signals on balanced male and female

XLR input plugs. Connectors for each channel are in parallel; any

unused

XLR connectors may be used for daisy-chaining input connec-

tions to other amplifiers.

In Parallel and Bridge Mono mode a signal applied to channel A’s input
connectors will appear also at channel B’s.

5

Input Sensitivity/Gain Switch

The Pro II Series amplifiers come standard set to x40 gain.
The Input Sensitivity/Gain switch allows the user to select either

.775

(0dB) sensitivity, x40, or x20 gain.

6

Fan Inlet Ports and Filters

Cooling air enters the amplifier through the fan inlet ports located on
the rear of the amplifier chassis.Be sure not to block these ports when
installing the amplifier or other associated equipment. Air must flow
unimpeded. Fan filters

(removable without tools) are provided to min-

imize entry of dust and dirt.

7

Input XLR Polarity Switch

Pro II Series amplifiers are supplied standard with the XLR configured
as Pin 2 hot

(+). Use the XLR polarity switch to change this setting to

Pin 3 hot

(+) if desired.

8

Signal Ground-Lift Switch

The recessed signal ground-lift switch electrically connects signal
ground to the chassis/

AC ground. This switch is factory-set to the

ground position

(bottom).The top position lifts the amplifier’s signal

ground.In a properly designed system

(for safety purposes and to min-

imize noise

),amplifiers should be connected to ground through the AC

line cord.

Whenever possible, the signal source equipment should share the
same

AC ground as the amplifier. In some cases this may not be possi-

ble, and a ground loop results. If this happens, the first step is to move
the ground-lift switch to the lifted position

(top).In this position, the sig-

nal ground is lifted and completely isolated from the chassis/

AC

ground. Do not change the switch to the lifted position if the amplifi­er and the signal source equipment are on the same

AC ground.

Should the ground loop problem persist after the ground-lift switch
has been set to the lifted position, then the shield on balanced input
lines should be grounded at one end only

(usually the signal source).

Never connect a hot (red)
output to ground or to
another hot (red) output!

a

p. 16

p. 17

operation modes

4

stereo

parallel

bridged

/

choosing the appropriate mode

/

switching between operation modes

/

keeping the amplifier cooled

/

special considerations when using bridged mode

Pro II owner’s manual

p. 18

operation modes

4

mode selection

The three-position,recessed Mode Select switch (located on the rear panel)
configures the amplifier for Stereo, Parallel or Bridged mode. Amplifiers are
factory-configured for Stereo mode.

stereo

In Stereo mode, both channels operate independently,with their input atten­uators controlling their respective levels. Signal at Channel A’s input produces
output at Channel A’s output,while signal at Channel B’s input produces out­put at Channel B’s output. Recommended minimum nominal load impedance
for stereo operation is 2 ohms per channel. Either the male or female

XLR

inputs may be used.

parallel

When set to Parallel mode, a signal applied to Channel A’s input will be ampli­fied and appear at outputs for both Channels A and B. Either the male or
female

XLR input on Channel A may be used. Individual channel attenuators

control signal level.

bridged

Bridged mode straps both amplifier channels together to make a very pow­erful, single-channel monaural amplifier. One channel “pushes” and the other
“pulls” equally, doubling the power over that of either channel alone.Signal is
applied to the Channel A input only. Channel A’s attenuator is used to con­trol signal level. Either male or female

XLR input may be used.

The channel B input connectors (male or female

XLR) may be used to daisy-

chain the channel A signal when in parallel or bridged mono mode. Use
extreme caution when operating the amplifier in Bridged mode. Never
ground either side of the speaker cable when the amplifier is in Bridged
mode; both sides are “hot.”

If an output patch panel is used, all connections must be isolated from each
other and from the panel.The recommended minimum nominal load imped­ance in the Bridged mode is 4 ohms, which is the equivalent to driving both
channels separately at 2 ohms.

see—connections for examples of mode-specific wirings

Driving bridged loads
of less than the recom­mended minimums will
activate the IGM circuitry,
resulting in a loss of power,
and may also lead to a
thermal protect condition.

a

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

a

p. 19

operation modes

4

p. 20

p. 21

connections

5

input

output

/

proper wiring schemes for connectors: XLR

speakon
binding post

/

correct signal paths: stereo, parallel, and bridged

Pro II owner’s manual

p. 22

connnections

5

inputs

Use either male or female XLR connectors on the rear to supply audio sig­nals to the inputs of your Crest Audio Pro II Series amplifier.

Pro II Series amplifiers are configured standard with pin 2 hot on

XLR inputs.

The input

XLR polarity switch can configure pin 3 hot if required.

outputs

Speakers are connected using the high-current five-way binding posts
or speakon connectors, or both, depending on preference and model.

see—operation modes

Some other Crest Audio
amplifiers are configured
with pin 3 hot.

a

Very high current is
available at the outputs.

Please connect your
output cable to the + and ­terminals of each section
precisely as shown.

a

The unused connector
can be used to jumper
the audio input to another
amplifier input.

+

2 - Positive (+)

3 - Negative (-)

1 - Ground ( )

stereo/parallel

female

XLR

male XLR

bridged mono

input sensitivity options

gain sens

position 1

Ø

.775V

position 2 x40 2.0V
position 3 x20 4.0V

p. 23

connections

5

stereo mode

five-way binding post connectors

parallel mode

five-way binding post connectors

bridged mono mode

five-way binding post connectors

Unused XLR connectors can be
utilized to daisy-chain a signal
source to additional amplifiers.

Unused XLR connectors can be
utilized to daisy-chain a signal
source to additional amplifiers.

Unused XLR connectors can be
utilized to daisy-chain a signal
source to additional amplifiers.

Pro II owner’s manual

p. 24

connnections

5

stereo mode

speakon output connectors

parallel mode

speakon output connectors

bridged mono mode

speakon output connectors

Unused XLR connectors can be
utilized to daisy-chain a signal
source to additional amplifiers.

Unused XLR connectors can be
utilized to daisy-chain a signal
source to additional amplifiers.

Unused XLR connectors can be
utilized to daisy-chain a signal
source to additional amplifiers.

p. 25

connections

5

p. 26

p. 27

safety

6

user
responsibility

speaker
protection

TourClass

/

the owner’s role in amplifier safety

/

description of TourClass protection features

/

protecting your speakers

Pro II owner’s manual

p. 28

safety

6

user responsibility

Your Pro II Series amplifier is very powerful and can be potentially dan­gerous to loudspeakers and operators alike. It is your responsibility to
read

important precautions (see the inside-front cover) and make

sure that the amplifier is installed, wired, and operated properly as
instructed in this manual.

Many loudspeakers can be easily damaged or destroyed by overpow­ering, especially with the high power available from a bridged amplifier.
Always be aware of the speaker’s continuous and peak power capabil­ities. Crest Audio is not responsible for damage to loudspeakers for
any reason.

see—speaker protection

p. 29

safety

6

speaker protection

All loudspeakers have electrical,thermal, and physical limits which must be
observed to prevent damage or failure. Cone or compression drivers can
be damaged

(sometimes to the point of failure) from excessive power, low

frequencies applied to high frequency drivers, severely clipped waveforms,
and

DC voltage. All Pro II Series amplifiers automatically protect speakers

from

DC voltages and subsonic signals.

see—TourClass protection

Mid- and high-frequency transducers—compression drivers in particular—
are highly susceptible to damage from overpowering, clipped waveforms,
or frequencies below their rated passband. When using an electronic
crossover, make absolutely certain that the low and mid bands are con­nected to the correct amplifiers and drivers

—and not accidentally con-

nected to those for a higher or lower frequency band.

The amplifier’s clipping point is its maximum peak output power. At max­imum peak output power, Crest Audio Pro II Series amplifiers will deliver
more power than many speakers can safely handle. Be sure the peak
power capability of the amplifier is not excessive for your speaker system.
To ensure that the speakers never receive excessive power, and to prevent
amplifier clipping, use a properly adjusted external limiter

(or a compres-

sor with a ratio of 10:1 or higher

) to control power output. Use one com-

pressor/limiter for each frequency band in systems with active electronic
crossovers.

The

ACL clip limiting circuit will automatically limit the duration of

squared-off, continuous waveforms applied to the speakers.The amplifier
will, however, allow normal musical transient bursts to pass. Of course,
when the amplifier does clip,it is operating at its maximum output power.
Note that some speaker systems are packaged with proprietary “proces­sors” that have power limiting circuits and therefore should not require
additional limiting.Do not drive any low-frequency speaker enclosure with
frequencies lower than its own tuned frequency; the reduced acoustical
damping could cause a ported speaker to “bottom out” even at moderate
power. Consult the speaker system specifications to determine its fre­quency limits, and employ a roll-off filter if necessary.

recommended speaker cabling

The wire gauge charts will assist you in determining the optimum copper
wire gauge for your speaker cables. Remember that the speaker cable
resistance robs amplifier power in two ways: through power lost directly
to resistance

(often referred to as I

2

R loss), and through increased total
load resistance, which decreases the amount of power available from the
amplifier. Appendix C gives cable length figures in feet/

AWG wire gauges

and in metric values.

see—wire gauge

Pro II owner’s manual

p. 30

safety

6

TourClass®protection

Every model in the Pro II Series incorporates TourClass protection fea­tures. Derived from Crest Audio’s extensive experience with the world’s
largest sound rental companies, the TourClass group of circuits sets the
industry standard for assured protection of internal amplifier circuits and
all connected loads.

ACL ACTIVE CLIP LIMITING

At the amplifier’s full power limit, or clipping point, ACL will be activated.
This is indicated by illumination of the

ACL LED.The channel gain is auto-

matically reduced,protecting the loudspeakers from potential damage from
the high power, continuous square waves that would otherwise be pro­duced.

ACL may be activated by uncontrolled feedback,oscillations,improp-

er equipment gain settings, or an equipment malfunction upstream from
the amplifier. Only steady or excessive clipping

(not normal program tran-

sients

) will trigger ACL. The circuit is virtually transparent in operation and

full signal bandwidth is maintained.

IGM INSTANTANEOUS GAIN MODULATION

IGM is an innovative circuit that allows the amplifier to operate safely into

loads as low as 2 ohms.When the amplifier sees a load that overstresses the
output stage, the

IGM circuit adjusts the channel gain to a safe level.Like ACL,

the IGM circuit is inaudible in normal use.In addition, if extreme and sustained
low impedance is encountered, the amplifier’s output relay will open.

AutoRamp

Auto Ramp operates every time the amplifier is turned on or is reactivated
after a protect condition is corrected. This exclusive Crest Audio feature
gradually increases gain to the attenuator setting avoiding unnecessary stress
on the loudspeakers.

Thermal

Abnormally high heat sink temperatures will engage the Protect circuit for the
overheating channel only.

(An output relay disconnects the loudspeakers until

nominal temperature range is restored.

) During this time, the Status LED will

light red. If the power supply gets too hot, its thermal sensing circuit will dis­connect both channel outputs. During this time, the

Active LED will extin-

guish, the Status

LED will remain red, and the cooling fan will continue run-

ning at high speed. Normal operation resumes once the power supply cools
to a safe level.

Short Circuit

If an output is shorted (i.e., defective speakers or crossed speaker wires) the

IGM and thermal circuits will automatically protect the amplifier.The IGM cir-

cuit senses the short circuit as an extremely stressful load condition and
attenuates the signal, protecting the channel’s output transistors from over­current stress. If the short circuit remains, the load will be disconnected by
the thermal protection circuitry

(the output relay opens).

p. 31

safety

6

DC Voltage

If an amplifier channel detects DC voltage at its output terminals, the out­put relay will immediately open to prevent loudspeaker damage.The

Status

LEDs will turn red.

Subsonic Frequencies

Built-in high pass filtering provides subsonic frequency protection for each
channel. In addition, a relay will open if excessive subsonic energy appears

at the output.

p. 32

p. 33

service and support

7

/

when to get support

/

ways to contact Crest Audio

support

contact us

Pro II owner’s manual

p. 34

service and support

7

support

In the unlikely event that your amplifier develops a problem, it must be
returned to an authorized distributor, service center or shipped directly to
our factory.

To obtain service, contact your nearest Crest Audio Service Center,
Distributor, Dealer, or any of the worldwide Crest Audio offices. For those
with Internet access, please visit the Crest Audio website.

contact us

customer service

phone [phone] USA
fax [phone] USA
email [e-mail]

technical support

phone [phone] USA
fax [phone] USA
email [e-mail]

website

www.crestaudio.com

mail

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

Because of the complexity
of the design and the risk
of electrical shock,
all repairs should be
attempted only by qualified
technical personnel.

a

If the unit needs to
be shipped back to the
factory, it must be sent
in its original carton.

If improperly packed, your
amplifier may be damaged.

a

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

+

p. 35

service and support

7

Pro II owner’s manual

p. 36

specifications

a

800W 750W

1400W 1350W

2000W 1900W

2800W 2700W

4000W 3800W

92V rms, 130V peak each channel

20Hz–20kHz, +0 / -0.3dB,-3dB@135kHz

20Hz–20kHz, +0 / -0.23dB

<0.05% rated power @ 4Ω, 1kHz

<0.01% rated power @ 8Ω, 60Hz and 7kHz

400:1 10–400Hz @ 8Ω

>60dB @ 1kHz

.775V constant sensitivity, x20 or x40 constant gain

>20kΩ balanced, >10kΩ unbalanced

-110dB, A-weighted below rated power

> -80dB @ 1kHz below rated power

H

two versions: 90–255 or 180–255 vac @ 50–60Hz factory configured
PowerLok power supply with active power factor correction

36A @ 120V

<7.7A @120V

<17.3A @120V

<50A @120V

<1.5A @120V

51A

2083 BTU/Hr

3899 BTU/Hr

back-to-front via two rear-mounted variable-speed DC fans

female and male xlr pin 2+

switch-configurable for pin 3+

speakon connectors and five-way output binding posts

front panel: two attenuators, power switch incorporating magnetic circuit breaker

rear panel: signal ground-lift, mode select, input sensitivity, pin 2/3+

acl, signal, status

bi-color: active / protect

acl, igm, autoramp, short circuit, dc voltage, turn-on/-off transient,
current in-rush, sub/ultrasonic input

aluminum chassis double thickness in rack-ear areas

5.25” x 19” x 18” 133 x 483 x 457mm

height x width x depth

gross:

47lbs 21.7 kg

net:

42lbs 19.1kg

five years USA, Canada, United Kingdom, and many other countries

Stereo power 8Ω

4Ω

2Ω

Bridged mono power 8Ω

4Ω

Maximum output voltage

Frequency response

1W @ 8Ω

Power bandwidth rated power @ 4Ω, 1% THD+N

THD+N

SMPTE IMD

Damping factor

Input

CMRR

Switch-configurable input options

Input impedance

Hum and noise

Crosstalk

Class

Power supply

Circuit breaker rating

4Ω

Current draw 1/8 power, 4Ω

1/3 power, 4Ω

at power-up

at idle

Peak current draw

Thermal emissions 1/8 Power, 4Ω

1/3 Power, 4Ω

Cooling

Input connectors

Output connectors

Controls

LED indicators

TourClass

®

protection

Construction

Dimensions

Weight

Warranty

1

kHz, 0.1% THD+N 20Hz–20kHz, 0.1% THD+N

see—connections for input sensitivity options

8002

p. 37

block diagram

b

Pro II owner’s manual

p. 38

wire gauge

c

stranded cable length

0.3mm

2

0.5

0.75

1.5

2.5

4.0

2.9%

1.74

1.16

0.58

0.35

0.22

5.6%

3.4

2.3

1.16

0.70

0.44

10.8%

6.7

4.5

2.3

1.39

0.87

0.5mm

2

0.75

1.5

2.5

4

6

4.3%

2.9

1.45

0.87

0.55

0.37

8.2%

5.6

2.9

1.74

1.09

0.73

15.5%

10.8

5.6

3.4

2.2

1.45

0.5mm

2

0.75

1.5

2.5

4

6

8.24%

5.6

2.9

1.74

1.09

0.73

5.5%

10.8

5.6

2.9

1.74

1.09

28%

19.9

10.8

6.7

4.3

2.9

0.75mm

2

1.5

2.5

4

6

10

15.5%

8.2

5.1

3.2

2.2

1.31

0.73%

15.5

9.8

6.3

4.3

2.6

45%

28

18.2

12.0

8.2

5.1

2

meters

5

meters

10

meters

30

meters

wire gauge power loss

8Ω load 4Ω load 2Ω load

p. 39

wire gauge

c

stranded cable length

18AWG

16

14

12

10

0.81%

0.51

0.32

0.20

0.128

1.61%

1.02

0.64

0.40

0.25

3.2%

2.0

1.28

0.80

0.51

18AWG

16

14

12

10

1.61%

1.02

0.64

0.40

0.25

3.2%

2.0

1.28

0.80

0.51

6.2%

4.0

2.5

1.60

1.01

18AWG

16

14

12

10

8

6.2%

4.0

2.5

1.60

1.01

0.60

11.9%

7.7

5.0

3.2

2.0

1.20

22%

14.6

9.6

6.2

4.0

2.4

18AWG

16

14

12

10

8

11.9%

7.7

5.0

3.2

2.0

1.20

22%

14.6

9.6

6.2

4.0

2.4

37%

26

17.8

11.8

7.7

4.7

5

feet

10

feet

40

feet

80

feet

wire gauge power loss

8Ω load 4Ω load 2Ω load

Crest Audio Inc.

100 Eisenhower Dr., Paramus NJ 07652 USA

TEL: [phone] FAX: [phone]

http://www.crestaudio.com

Ch A Ch B

-

80

-

30

-

15

-

10

-

6

-

3

-

1

ØdB

-

80

-

30

-

15

-

10

-

6

-

3

-

1

ØdB

8002

Professional Power Amplifier

Status

Signal

ACL

v. 1.0 4/29/98

*A4400076*