Crown CH2 User manual

Crown Audio, Inc.
P.O. Box 1000
Elkhart, IN 46515-1000
TEL: [phone]
FAX: [phone]FAX
www.crownaudio.com
CH2
9/05 131954-1B
Specifications subject to change without prior notice. Latest
information available at www.crownaudio.com.
Crown®is a registered trademark of Crown International, Inc.
Printed in U.S.A.
© 2005 Crown Audio, Inc.
Architectural & Engineering Specifications
CONTRACTOR SERIES
CH2 (120V, 60 Hz models)
The amplifier shall be a solid-state two-channel model. Each amplifier
channel shall have the ability to operate individually, or paired with the
other channel in a bridged configuration to provide increased output volt-
age over that of an individual channel output. The outputs shall be switch-
able for either low impedance (standard speaker load) or high impedance
(distributed speaker line) operation. When in 70V (high impedance)
operation, a 70 Hz high-pass filter shall be employed in the signal chain to
prevent step-down transformer saturation.
Front panel controls shall include a rocker switch for selecting power
on and off. Rear panel controls shall include a recessed detented rotary
control for each channel to adjust input level, a recessed switch to select
Stereo or Bridge modes of operation, a recessed switch to select 4/8 ohm
or 70V operation, and a reset switch for the AC mains circuit breaker.
Internal controls shall include a jumper block to allow selection of input
sensitivity of either 0.775V or 26 dB gain as a service option. Sensitivity
shall be factory-set to 1.4V.
Front panel indicators shall include a green LED to indicate that the ampli-
fier is turned on and power is applied; a red LED for each channel which
shall blink to indicate any of the following 5 conditions: 1) When the
amplifier is first powered up, until the unit is ready for operation. 2) If
the heatsinks reach a temperature above normal working limits. 3) If the
transformer thermal protection circuit is activated. 4) If the amplifier wires
develop a short circuit, and 5) should the amplifier output stage become
non-operational; a red LED for each channel which shall turn on to indicate
when distortion of any type becomes audible in the amplifier output; and
a green LED for each channel which shall flash dimly to indicate when a
low-level signal (> -40 dBm) is present at the input of the amplifier.
Rear-panel connectors shall include an XLR connector in parallel with a
three-terminal barrier block for each channel for balanced input connection
(on the standard input module); a four-terminal touch-proof barrier block
for each channel for output connection (on the standard output module);
and an RJ11 jack for connection to an external circuit for the purpose of
remotely monitoring fault conditions.
The amplifier power requirements shall be 120 VAC, 9.5 A at 60 Hz. A
detatchable IEC 15A to NEMA 5-15P AC line cord shall be provided for AC
connection. Typical quiescent power draw shall be 60 watts.
The amplifier chassis shall be constructed of steel with a durable black
finish. The amplifier shall employ a cooling system consisting of internal
heat exchangers, along with a variable-speed cooling fan which shall oper-
ate according to internal thermal demand. Airflow through the chassis shall
be from front to rear.
The dimensions of the amplifier shall allow for 19 inch (48.3 cm) EIA Stan-
dard (RS-310-B) rack mounting. The amplifier shall be 5.25 inches (13.34
cm) tall and 12.25 inches (31.11 cm) deep behind the rack-mounting
surface. The amplifier shall weigh 48.3 pounds (21.9 kg).
The amplifier shall be protected against shorted, open or mismatched
loads; overloaded power supplies; excessive temperature; chain destruc-
tion phenomena; input overload damage; and high-frequency blowups.
The amplifier shall protect loudspeakers from input/output DC, large or
dangerous DC offsets and turn-on/turn-off transients.
Nominal input impedance of the amplifier shall be 20 k ohms, balanced;
10 k ohms, unbalanced.
The power amplifier shall meet or exceed the following performance criteria
(amplifier in stereo mode with 8 ohm loads and an input sensitivity of
26 dB gain, 1 kHz at rated power unless otherwise specified): Load imped-
ance (safe with all types of loads): 4 and 8 ohm Stereo; 8 ohm at 70V
Stereo; 8 and 16 ohm Bridge; 16 ohm at 140V Bridge. Voltage gain, 1 kHz,
1.4V sensitivity: 32.1 dB (4/8 ohm); 34 dB (70V). Output Power at 1 kHz
at rated THD; in Stereo mode at 8 ohms: 400 watts per channel; in Stereo
mode at 4 ohms: 660 watts per channel; in Stereo mode, 70V operation:
600 watts per channel; in Bridge mode at 8 ohms: 1,320 watts; in Bridge
mode, 140V operation: 1,200 watts. Frequency Response, 20 Hz to 20 kHz
at 1 watt: ±0.1 dB. Phase Response: ±15 degrees deviation from linear
phase from 20 Hz to 20 kHz at 1 watt. Signal to Noise Ratio, A-Weighted:
Better than 105 dB below rated 1-kHz power. Total Harmonic Distortion
(THD), 1 kHz at rated power: 0.5% or less true THD from 20 Hz to 20 kHz.
Intermodulation Distortion (60 Hz and 7 kHz at 4:1): Less than 0.1% at
rated power to 30 dB below rated power at 8 ohms. Damping Factor (8
ohm): Better than 400 from 10 Hz to 400 Hz. Crosstalk, 20 Hz to 20 kHz:
Better than 50 dB below rated power. Common Mode Rejection (CMR):
Better than 40 dB from 20 Hz to 1 kHz. DC Output Offset (Shorted Input):
±10 mV.
The amplifier shall be designated the Crown CH2.