Crown Audio I Leaflet

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Crown International
1718 W. Mishawaka Rd.
Elkhart, IN 46517-9439
TEL: 574-294-8200
FAX: 574-294-8FAX
www.crownaudio.com
STUDIO 
REFERENCE 
I
04/05                                                             138313-1  
 
Specifications subject to change without prior notice. Latest 
information available at www.crownaudio.com. 
Crown and Crown Audio are registered trademarks of Crown 
International, Inc. Printed in U.S.A.
© 2005 Crown Audio
®
, Inc.
Architectural & Engineering Specifications
S T U D I O   R E F E R E N C E   S E R I E S
Studio Reference I (120 V, 60 Hz models)
The Crown
®
 
Studio Reference I power amplifier shall be a solid-state two-channel 
model employing multi-mode (AB+B) grounded bridge(TM) output circuitry with a 
variable impedance (VZ) power supply for each channel.
The outputs shall be switchable as stereo, bridged-mono or parallel-mono modes 
of operation. The bridged-mono mode shall bridge the outputs to provide increased 
output voltage. The parallel-mono mode shall parallel the outputs to provide 
increased output current.
The output impedance of each channel shall be less than 10 milliohms in series with 
less than 2 microhenries in stereo mode.
The variable impedance power supplies shall reduce unnecessary voltage across the 
output devices by automatically switching to a parallel mode when less voltage is 
required by the output circuitry and to a series mode when more voltage is required.
The amplifier shall contain protection circuitry which limits the drive level placed on 
the output devices before their SOA (Safe Operating Area) is exceeded. This protec-
tion circuitry shall calculate the instantaneous voltage across and current through 
the output devices while factoring in their simulated junction temperatures to predict 
how close they are to their operating limits. This protection will be called “ODEP.”
The amplifier shall contain controlled slew-rate voltage circuitry to protect it against 
radio frequency interference burnouts. It shall also be protected from current over-
load at its output stage. The slew rate of the amplifier shall be greater than 30 volts 
per microsecond in stereo mode.
The amplifier shall temporarily go into a stand-by mode if its power transformer 
becomes excessively hot and shall automatically resume normal operation once it 
has cooled to a safe operating temperature.
Front-panel controls shall include an enable on/off switch and a detented input level 
control for each channel.
Rear-mounted controls shall include a ground lift switch to isolate the signal ground 
from the chassis ground, a switch which selects between stereo, bridged-mono and 
parallel-mono modes of operation and a reset switch for the AC mains circuit breaker.
Internal controls shall include an input sensitivity switch to select between 0.775 V, 
1.4 V or a fixed voltage gain of 26 dB for full rated output.
A Crown P.I.P. and P.I.P.2-compatible expansion connector shall be provided behind 
an access panel in the rear to accept auxiliary input modules. It shall be fully compat-
ible with the Crown IQ System.
Front panel indicators shall include an amber power enable indicator, an amber ODEP 
protection system indicator for each channel which shall normally be illuminated 
to confirm the availability of reserve thermodynamic energy and which shall dim 
in proportion to limiting when the power demands of the output stages have been 
exceeded, a green IOC indicator for each channel, and a green Signal indicator for 
each channel which shall normally flash at moderate intensity to show the presence 
of an audio signal.
The power amplifier shall meet or exceed the following performance criteria. Input 
sensitivity for rated output: 26 dB voltage gain (unbalanced). Rated FTC output in 
stereo mode with less than 0.1% THD: 780watts per channel (20 Hz to 20 kHz) into 
8 ohms. Hum and noise: at least 120 dB (A weighted) below full rated output power. 
Phase response: +5 to –15 degrees from 20 Hz to 20 kHz at 1 watt. Frequency 
response: 20 Hz to 20 kHz, 0.1 dB at 1 watt into 8 ohms per channel in stereo mode. 
Damping factor: greater than 20,000 from 10 to 200 Hz into 8 ohms. Intermodulation 
distortion (SMPTE): less than 0.005% from full bandwidth power to 78 watts rising 
linearly to better than 70 dB at 20 kHz. Harmonic distortion: less than 0.02% at rated 
low-distortion 1 kHz power.
The amplifier shall be safe when driving any kind of load—even highly reactive ones.
The power requirements shall be 120 VAC at 60 Hz. At idle, the amplifier shall draw 
90 watts or less.
The amplifier chassis shall be constructed of steel with a durable black finish and 
shall be designed for flow-through fan-assisted ventilation from the front panel to the 
side panels. The amplifier shall have an aluminum front panel with super-gloss Imron 
finish and Lexan overlay.
The dimensions of the amplifier shall allow for 19 inch (48.3 cm) EIA standard (RS-
310-B) rack mounting. The amplifier shall be 7 inches (17.8 cm) tall, 16 inches (40.6 
cm) deep behind the rack-mounting surface, and 2.75 inches (7 cm) in front of the 
rack-mounting surface.
The amplifier shall weigh 60 pounds, 11 ounces (27.6 kg) and shall have a center of 
gravity approximately 6 inches (15.2 cm) behind the front panel.
The amplifier shall be designated the Crown Studio Reference I.