Crest Audio CA 9 Owners Manual

Page 1

CRESI'
AUDIO

PROFESSIONAL POWER AMPLIFIERS

OWNERS MANUAL

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Important Precautions

This symbol is used to aien the operr
ator to toilow important operating
procedures and precautions detailed
in documentation.

This symbol is used to warn operar
tors that uninsulated dangerous voitr
ages" are present within the equip
ment enclosure that may pose a risk

of electric shock.

. Save the carton and packing material

even if the equipment has arrived in
good condition. Should you ever need
to ship the unit, use only the original
factory packing.

Read all documentation before oper-
ating your equipment. Retain all doc-
umentation for future reference.

. Follow all instructions printed on unit

chassis for proper operation.

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

Make sure power outlets conform to
the power requirements listed on the
back of the unit.

Do not use the unit if the electrical
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, paying particular atten-
tion to cords and plugs, convenience
receptacles, and the point where they
exit from the appliance.

Always operate the unit with the AC
ground wire connected to the electri-
cal system ground. Precautions should
be taken so that the means of ground-
ing of a piece of equipment is not
defeated.

Mains voltage must be correct and
the same as that printed on the rear
of the unit. Damage caused by connec-
tion to improper AC voltage is not cov-
ered by any warranty.

Have gain controls on amplifiers
turned down during power-up to pre-
vent speaker damage if there are high
signal levels at the inputs.

10. Power down 8; disconnect units from
mains voltage before making connec-
tions.

11. Never hold a power switch in the
ON position if it wont stay there
itself!

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

13. 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 environ-
ment, the unit should be periodically
blown free of foreign matter.

14. Do not remove the cover. Removing
the cover will expose you to potentially
dangerous voltages. There are no user
serviceable parts inside.

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

16. Do not drive the inputs with a signal
level greater than that required to
drive equipment to full output.

17. Do not connect the inputs / outputs
of amplifiers or consoles to any other
voltage source, such as a battery,
mains source, or power supply, regard-
less of whether the amplifier or console
is turned on or off.

18. Do not run the output of any amplifi-
er channel back into another chan-
nels input. Do not parallel- or
series-connect an amplifier output
with any other amplifier output.
Crest Audio is not responsible for dam-
age to loudspeakers for any reason.

19. Do not ground any red (hot) ter-
minal. Never connect a hot (red)
output to ground or to another hot
(red) output!

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

21. Service Information E q u i p m e n t
should be serviced by qualified service
personnel when:

A. The power supply cord or the plug
has been damaged;

B. Objects have fallen, or liquid has
been spilled into the equipment;

C. The equipment has been exposed to
rain;

D. The equipment does not appear to
operate normally, or exhibits a
marked change in performance;

E. The equipment has been dropped,
or the enclosure damaged.

22. To obtain service, contact your nearest
Crest Audio Service Center,
Distributor, Dealer, or Crest Audio at
201.909.8700 (USA).

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AUDIO

Rear Panel See Appendix Efar information Specific to model CAIS.

.4

10. Output Connectors (Two versions, market dependent)

CA Series amplifiers are supplied with either 5-way Binding Posts or Speakon connectors. Connection to
the binding posts can be made with bare wire, banana plugs, 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 Speakon-type speaker
cables, make connections to both the Channel A and Channel B connectors for Stereo or Parallel Mode, or
to the Bridged mode connector for Bridged Mono Mode. See Appendix D and the section on Mode
Selection for more information. NOTE: on the 5 -way Output Binding Post version of the CA18, two pairs

of 5-way binding posts are provided for each channel, so that paralleling of speakers is possible.

11. Mode Selection Switch. Never connect a hot (red) output to ground
or to another hot (red) output!

This recessed, three-position switch configures the
amplifier for Stereo, Parallel or Bridged Mono Mode operation. Amplifiers are factory-configured for
Stereo Mode. See Appendix D and the section on Mode Selection for more information.

12. Signal Ground Lift Switch.

The recessed signal ground lift switch (factory-set to the ground [bottom] position) electrically connects
signal ground to the chassis/AC ground. The top position lifts the amplifiers signal ground. In a properly
designed system (for safety purposes and to minimize noise), amplifiers should be connected to ground
through the AC line cord. Also, whenever possible, the signal source equipment should share the same AC
ground as the amplifier. In some cases this may not be possible, and a ground loop results. If this happens,
the first step is to move the ground lift switch to the top (lift) position. In this position, the signal ground is
lifted and completely isolated from the chassis/AC ground. Do not change the switch to the lift 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 lift position, then the shield on balanced input lines
should be grounded at one end only (usually the signal source).

Crest Audio CA Series Power Amplifiers Page 7
Models CA2, CA4, CA6, CA9, CA12, CA18