Specifications
INSTALLED SOUND
11
As part of the Contractor (CH/CL) Series, Crown delivers three mod-
els (CH1, CH2 and CH4) designed for both low and high impedance
outputs per channel, with each channel independently capable of
providing 4/8-ohm, 70V or 100V operation. The powerful and flexible
CH Series amplifiers also include 70-Hz high pass filters on each
channel, giving you the necessary low frequency rolloff to eliminate
the saturation of constant voltage step-down transformers typically
used in 70V and 100V distributed systems.
Specifications
Note: All measurements apply to all models of CH series amplifiers in stereo mode with 8-ohm
loads and an input sensitivity of 26-dB gain, 1-kHz at rated power unless other otherwise
specified. Specifications for units supplied outside the U.S.A. may vary slightly at different AC
voltages and frequencies.
Power
Load Impedance: Safe with all types of loads.
CH1: 4 and 8 ohm Stereo; 16 ohm at 70V Stereo; 32 ohm at 100V
Stereo; 8 and 16 ohm Bridge; 32 ohm at 140V Bridge; 64 ohm at
200V Bridge.
CH2: 4 and 8 ohm Stereo; 8 ohm at 70V Stereo; 16 ohm at 100V
Stereo; 8 and 16 ohm Bridge; 16 ohm at 140V Bridge; 32 ohm at
200V Bridge.
CH4: 4 and 8 ohm Stereo; 4 ohm at 70V Stereo; 8 and 16 ohm Bridge;
8 ohm at 140V Bridge.
Voltage Gain, 1 kHz, 1.4V sensitivity,
CH1: 30.5 dB (4/8 ohm); 34 dB (70V); 37 dB (100V).
CH2: 32.1 dB (4/8 ohm); 34 dB (70V); 37 dB (100V).
CH4: 34 dB (4/8 ohm); 34 dB (70V).
AC Line Requirements: CL1, CL2: 60 Hz. CL4: 50/60 Hz.
AC Line Current (no signal):
CH1: 100 Volts: 7.6 A; 120 Volts: 6.3 A; 230-240 Volts: 3.5 A.
CH2: 100 Volts: 11.4 A; 120 Volts: 9.5 A; 230-240 Volts: 5.0 A.
CH4: 100 Volts: 8.5 A; 120 Volts: 7.1 A; 230-240 Volts: 3.7 A.
AC Line Connector: Detachable 15A IEC connector with country-specific plug.
Performance
Frequency Response, 20 Hz to 20 kHz at 1 watt:
CH1, CH2: ±0.1 dB.
CH4: ±0.25 dB.
Phase Response: ±15 degrees from 20 Hz to 20 kHz at 1 watt.
Signal to Noise Ratio, A-Weighted,
CH1, CH2: Better than 105 dB below rated 1-kHz power.
CH4: Better than 102 dB below rated 1-kHz power.
Total Harmonic Distortion (THD) at rated power: 0.5% or less.
Intermodulation Distortion (60 Hz and 7 kHz at 4:1):
CH1, CH2: Less than 0.1% at rated power to 30 dB below rated power
at 8 ohms.
CH4: Less than 0.5% at rated power to 30 dB below rated power at 8
ohms.
Damping Factor (8 ohm),
CH1, CH2: Better than 600 from 10 Hz to 400 Hz.
CH4: Better than 1000 from 10 Hz to 400 Hz.
Crosstalk, 20 Hz to 20 kHz:
CH1, CH2: Better than 50 dB below rated power.
CH 4: Better than 50 dB below rated power at 10 kHz.
Common Mode Rejection (CMR): Better than 40 dB from 20 Hz to 1 kHz.
DC Output Offset (Shorted Input): ±10 mV.
Controls
Level: A detented rotary level control for each channel located on the rear panel.
Power: An on/off rocker switch located on the front panel.
Mode: Two-position switch. “Stereo” operates the amplifier as two inde-
pendent channels. “Bridge” bridges the two output channels for twice
the output voltage.
Channel Operation Switch: Two-position switch: “4/8 Ohm” drives low-
impedance speaker loads. “70V/100V” (70V only on the CH4) drives
distributed high-impedance speaker loads; inserts 70-Hz high-pass fil-
ter to prevent step-down transformer saturation.
Indicators
Signal: A green indicator for each channel which flashes when a very low-
level signal (>–40 dBm) is present at input. May be used for trou-
bleshooting cable runs.
Clip: A red indicator for each channel which turns on when distortion
becomes audible in the amplifier output.
Fault: A red indicator for each channel which indicates amplifier has
muted output. Normally off. Status may be monitored remotely by
plugging into back-panel RJ11 Fault jack.
Power: A blue indicator that turns on when the amplifier has been turned
on and has power.
Input/Output
Input Connector (standard module): One Neutrik Combo connector for each
channel (balanced ¼-inch [6.35-mm] phone jack and 3-pin female XLR
connector, in parallel with a barrier strip termination).
Input Stage: Electronically balanced with precision 1% resistors.
Input Impedance: Nominally 20 k ohms balanced. Nominally 10 k ohms
unbalanced.
Input Sensitivity: Channel independent. Factory set at 1.4 volts for stan-
dard 1-kHz, 8-ohm power. 26-dB gain and 0.775-volt sensitivity avail-
able as a Service Option.
Output Connectors:
CH1 and CH2: Four-terminal touch-proof barrier block, one per chan-
nel, connects to 8-ohm, 4-ohm, 70V or 100V outputs.
CH4: Four-terminal touch-proof barrier block.
Output Signal,
Stereo: Unbalanced, two-channel.
Bridge-Mono: Balanced, single-channel. Channel 1 controls are active;
Channel 2 should be turned down.
Protection: Protected against shorted, open or mismatched loads; over-
loaded power supplies; excessive temperature, chain destruction phe-
nomena, input overload damage and high-frequency blowups. They
also protect loudspeakers from input/output DC, large or dangerous
DC offsets and turn-on/turn-off transients.
Construction: Rugged steel chassis, coated with environmentally friendly
powder for long life and ease of maintenance.
Cooling: Proportional speed fan.
Dimensions:
Width (all models): EIA Standard 19-inch rack mount (EIA RS-310-B);
Height (all models): 5.25-inch (13.34-cm);
Depth (behind front mounting surface):
CH1, CH2: 12.25-inch (31.11-cm); CH4: 16.25-inch (36.56-cm).
Weight
CH1: 40.6 pounds (18.4 kg); CH2: 48.3 pounds (21.9 kg);
CH4: 33.3 pounds (15.1 kg).
For shipping weight, add 6 pounds (2.7 kg) to each amplifier’s weight.
System Solutions:
SST Modules: SST-SBSC: variable Linkwitz-Riley stereo crossover
with mono-summed sub-bass outputs; SST-MX: 100-Hz Linkwitz-Riley
crossover with stereo sub-bass output; SST-SX: 80-/120-Hz switch-
able Linkwitz-Riley crossover with mono summed sub-bass output,
ScreenArray
®
SST modules.
Regulatory Certifications: