Crest Audio CPA400 User manual

description features
TourClass
®
protection circuits
acl active clip limiting prevents speaker damage by
providing gentle gain reduction at the clipping threshold.
igm instantaneous gain modulation monitors speaker loads to
detect conditions that may overstress output devices, allowing safe
operation into difficult impedances.
autoramp gradually increases gain to the attenuator level-
settings when the amplifier is turned on.
Protection features include: short circuit, dc voltage,
comprehensive thermal management, current in-rush turn-
on/off transient, and sub/ultrasonic input.
The Crest Audio CPA400 professional power amplifier is
designed to achieve unsurpassed sonic performance and long-
term reliability – even when operating under extreme stress
– in touring or fixed installation applications.
Absolute sonic accuracy is the hallmark of every Crest ampli-
fier. Bass is solid and defined to the limits of audibility, with
ample current reserves delivered by an “over-engineered”
power supply and advanced Class AB output circuit design.
Wide-bandwidth output devices assure detailed, transparent
high frequency response. And, thanks to Crest’s exclusive
IGM circuit, the CPA400 will drive 2 Ω loads safely without
compromise in performance.
Construction and Quality Control
The CPA400 is built exclusively in Crest’s own USA manu-
facturing facility, with internal components selected for pre-
mium quality and proven durability. Each modular
subassembly is pre-tested, and the assembled CPA400 receives
a rigorous “hot room” burn-in before thorough final check-
out on precision test equipment
.Crest’s legendary “overbuilt” power supply
.toroidal power transformer
.latest generation of high-speed, wide-bandwidth output devices
.twin tunnel cooling with back-to-front air flow
.dual, variable speed DC fans
.massive, extruded aluminum heat sinks
.balanced XLR and 1⁄4-inch (TRS) inputs
.five-way binding post outputs or Speakon™connectors
(market dependent)
.stereo/parallel/bridged mono mode selector switch
.ground lift switch
.input sensitivity selection
.recessed, stepped attenuators
.front panel circuit breaker switch
.modular construction
.five-year warranty*
power specifications 8Ωstereo 4Ωstereo 2Ωstereo 8Ωbridged 4Ωbridged
1kHz, 0.01% THD 250w 435w 500w 830w 1100w
20Hz-20kHz, 0.1% THD+N 245w 400w 450w 800w 900w
Power figures are watts per channel, both channels driven.
CPA400
CPA400 power amplifier
4Ωstereo CPA600 CPA900 CPA1200 CPA1800
1kHz, 0.01% THD+N 600w 900w 1200w 1800w
20Hz-20kHz, 0.1% THD+N 500w 800w 1100w 1700w
power specifications:
other CPA Series power amplifiers

1kHz, 0.1% THD+N 20Hz–20kHz, 0.1% THD+N
250W245W
435W400W
500W450W
830W800W
1000W900W
58V rms, 82V peak each channel
20Hz–20kHz, +0 / -0.3dB,-3dB@135kHz
20Hz–20kHz, -.9dB/ +.5dB
<0.01% rated power @4Ω, 1kHz
<0.01% rated power @ 8Ω, 60Hz and 7kHz
550:1 10–400Hz @8Ω
>-60dB @1kHz
.775Vstandard, (switchable; see table below)
X61 standard, (switchable; see table below)
>20kΩ balanced, >10kΩ unbalanced
-105dB, A-weighted full power @ 4Ω
> -60dB A-weighted full power @ 4Ω
AB
100–240 vac @50–60Hz factory configured
36A @120V
<6.8A @120V
<10.0 @120V
<15.0A @120V
<1.4A @120V
15A
2030 BTU/Hr
2726 BTU/Hr
back-to-front via two rear-mounted variable-speed DC fans
(filters removable without tools)
female xlr pin 2+ dealer-configurable for pin 3+ trs (tip+)
speakon connectors or five-way output binding posts
front panel: two attenuators,
rear panel: signal ground-lift switch, mode select switch
acl, signal, temp/dc: active
acl, igm, autoramp, short circuit, dc voltage, turn-on/-off transient,
current in-rush, sub/ultrasonic input
steel chassis, 16-gauge double thickness in rack-ear areas
3.5" x 19" x 18" 89mm x 483 x 457mm height x width x depth
gross: 46lbs 20.88kg
net: 41lbs 18.61kg
five years* USA, Canada, United Kingdom, and many other countries
specifications
Crest Audio Inc.
100 Eisenhower Dr., Paramus NJ 07652 USA
TEL: [phone] FAX: [phone]
http://www.crestaudio.com
*A4500001*
CPA400 power amplifier
The power amplifier shall have two channels.
At 8Ω, 20Hz - 20kHz, 0.1% THD+N, it shall
deliver a minimum of 245 watts per channel.
At 4Ω, 20Hz - 20kHz, 0.1% THD+N, it shall
deliver a minimum of 400 watts per channel.
In bridged mono mode with an 8Ωload,
20Hz - 20kHz, 0.1% THD+N, it shall deliver a
minimum of 800 watts.
Two rear panel mounted variable speed DC
fans (filters detachable without tools) shall pro-
vide back to front air flow through the chassis.
The amplifier shall have circuitry to protect
itself from output short circuits, thermal over-
load or other adverse load conditions. The
amplifier shall protect speaker loads from DC
voltage on outputs. The amplifier shall have
active clip limiting and impedance sensing cir-
cuitry. Output relays shall protect the speak-
ers from amplifier failure.
Each channel shall have a standard (factory-
set) input sensitivity of 0.775 Volts, and shall
be fitted with an internal jumper which allows
the gain to be altered to X20 or X40. The
hum and noise level shall be 105 dB below
rated output, “A” weighted. SMPTE IMD shall
be less than 0.01% at rated power, 60Hz
and 7kHz. The amplifier shall have a class AB
output stage. The frequency response shall be
20Hz-20kHz, +0, -0.3dB (1W/8Ω).
The amplifier will operate at 100V-240V,
50-60 Hz AC (configured at factory).
Maximum current draw shall not exceed 15
amperes at 120VAC (limited by front panel
breaker for bench tests).
Front panel indicators shall include ACTIVE,
PROTECT, SIGNAL, and CLIP LED’s for each
channel. Front panel attenuators shall be
recessed and detented.
Rear panel input connectors shall be female
TRS and XLR type, internally dealer-config-
urable for pin 2 (factory setting) or pin 3 posi-
tive. Output terminations shall be 5-way
output binding posts or Speakon output con-
nectors (market dependent). A ground lift
switch and a Stereo/Parallel/Bridged Mono
mode operation switch shall be provided.
A rear-panel IEC AC mains socket (with power
cord) or single AC mains cord having an appro-
priate AC plug for the intended operating volt-
age shall be provided (market dependent).
The packaging of the amplifier shall allow for
standard rack mounting without requiring space
between similar units. Optional rack mount han-
dles will be available. Dimensions shall be 19"
(483mm) wide, 3.5" (89mm) high and 18"
(457mm) deep. The amplifier shall weigh
41 lbs. (18.61 kg.) net, and shall be desig-
nated the Crest Audio model CPA400.
v. 1.0 10/5/98
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
input sensitivity rated power @ 8Ω
voltage gain
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
architect’s specifications
Crest Audio specification literature is available
in downloadable PDF format at our website
http://www.crestaudio.com
Power figures are watts per channel,
both channels driven.
©¹⁹⁹⁸ crest audio inc.
Crest Audio reserves the right to make
improvements in manufacturing or design
which may affect specification.
rear view CPA400
Power figures are
watts per channel,
both channels driven.
*Three-year Warranty
with two additional years,
if Registration Card is
sent to Crest Audio.
dealer-configurable gain/
sensitivity options
gain sens
factory standard x61 .775V
option1 x40 1.12V
option 2 x20 2.24V