Crown 660A Commercial Audio Amplifier

The Crown 660A is a six-channel commercial audio amplifier designed for background music, paging, and public address applications across schools, hospitals, factories, retail spaces, and corporate environments. Each channel delivers 60 W at 4 ohms, with channels 1–4 offering selectable constant-voltage outputs at 70 V and 100 V, and channels 5–6 providing 4-ohm outputs. The modular architecture enables independent zone control, making it ideal for facilities requiring multi-area audio distribution.

## Technical Specifications

• **Power Output:** 60 W per channel at 4 ohms
• **Constant-Voltage Outputs:** 70 V and 100 V on channels 1–4; channels 5–6 provide 4-ohm outputs
• **Frequency Response:** 100 Hz to 19 kHz ±1 dB (4-ohm tap at 1 W); 20 Hz to 20 kHz ±1 dB (line out)
• **Signal-to-Noise Ratio:** 85 dB (referenced to rated power, master volume at minimum)
• **Total Harmonic Distortion:** <0.5% at rated power, 1 kHz
• **Input Sensitivity:** 800 mV for full output at maximum gain
• **Input Impedance:** 100 kilohms (nominal)
• **Crosstalk:** –70 dB at 1 kHz
• **DC Output Offset:** <±5 mV
• **Minimum Load Impedance:** 160 ohms (100 V output), 80 ohms (70 V output), 4–8 ohms (4-ohm output)

## Key Features

• Six independent output channels for multi-zone deployment
• Balanced 3-pin Phoenix-type inputs, one per channel
• Terminal strip outputs accept up to 10 AWG wire forks
• Voltage-controlled amplifier (VCA) connectors for each channel pair (+10 VDC control lines)
• Volume controls per channel with detented potentiometers
• Output current limiting, DC protection, thermal protection, and circuit breaker/fuse
• Convection-cooled design
• AC line voltages: 100 V 50/60 Hz, 120 V 60 Hz, 220 V 50/60 Hz, 230 V 50/60 Hz
• AC voltage tolerance: +10% / –20%

## Physical & Integration

• 19-inch EIA standard rack mount, 2U height (3.5 inches)
• Depth: 12.2 inches behind mounting surface; 13.9 inches total from knob fronts
• Convection-cooled operation requires adequate airflow