D SEries 30 CHANNEL 1 20 40 50 LEVEL 30 50 HEADPHONES CHANNEL 1 20 0 0 IOC SIGNAL POWER 30 OFF ON 20 40 50 10 LEVEL LEVEL CHANNEL 2 ON 10 IOC SIGNAL 0 40 OFF 20 40 50 10 HEADPHONES 30 CHANNEL 2 10 LEVEL 0 POWER Models: D-45 & D-75A Some models may be exported under the name Amcron.® © 1996 by Crown International, Inc., P.O. Box 1000, Elkhart, Indiana 46515-1000 U.S.A. Telephone: 219-294-8000.
3 YEAR THREE YEAR FULL WARRANTY 3 YEAR WORLDWIDE NORTH AMERICA SUMMARY OF WARRANTY The Crown Audio Division of Crown International, Inc., 1718 West Mishawaka Road, Elkhart, Indiana 46517-4095 U.S.A.
The information furnished in this manual does not include all of the details of design, production, or variations of the equipment. Nor does it cover every possible situation which may arise during installation, operation or maintenance. If your unit bears the name “Amcron,” please substitute it for the name “Crown” in this manual. If you need special assistance beyond the scope of this manual, please contact our Technical Support Group. Crown Audio Division Technical Support Group Plant 2 SW, 1718 W.
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D-45 / D-75A Power Amplifiers This standard stereo phone jack is used to connect headphones This indicator flashes synchronously with the Channel 1 output to show signal presence This knob controls the Channel 1 and left headphone output levels 30 50 LEVEL 0 ® INTERNATIONAL, INC. ELECTRONIC EQUIPMENT 50 IOC SIGNAL LEVEL 0 POWER Barrier block output connectors Channel 1 combination XLR/phone input connector REMPLACER SEULMENT CH-2 INPUTS CH-1 XLR WIRING 3 GND 0000 + 000000 MODEL AMPS.
D-45 / D-75A Power Amplifiers 2 Installation D-45 and D-75A amplifiers are designed for standard 19 inch (48.3 cm) rack mounting, or they can be stacked without a cabinet. Before mounting your amplifier, determine whether you need to change the amplifier’s internal settings for your application. tors are located on the back panel. If you are making changes to a unit that is already installed, make sure the power is disconnected and the level controls are turned down.
D-45 / D-75A Power Amplifiers DUAL MODE FROM THE FACTORY, YOUR AMPLIFIER IS CONFIGURED FOR DUAL OPERATION MIXER CHANNEL 2 REMPLACER SEULMENT CHANNEL 1 CH-2 INPUTS CH-1 XLR WIRING 3 GND 2 PHONE WIRING CH-1 OUTPUTS + IMPORTANT: IN MONO MODE USE THE CH-1 INPUT ONLY.
D-45 / D-75A Power Amplifiers 5. Do not use connectors with any tendency to short. High-frequency oscillations can cause your amplifier to prematurely activate its protection circuitry. To prevent high-frequency oscillations, follow these guidelines: 1. If you have long cable runs or different amplifiers sharing a common tray or jacket, use tie-wraps to bundle together loose pairs of loudspeaker conductors. (Do not bundle wires from different amplifiers.
D-45 / D-75A Power Amplifiers 4. Using a soldering iron, change the appropriate jumpers for the desired operating voltage (see Figure 2.3). 5. Install an appropriate fuse: 2 amp type 3AG for 100 or 120 VAC mains, and 1 amp type 3AG for 200, 220 or 240 VAC mains. 6. Carefully check all connections. 7. Repeat steps 1 and 2 in reverse order to reassemble the unit. IMPORTANT: Only use 2 amp type 3AG fuses for 100 or 120 VAC operation, and 1 amp type 3AG fuses for 200, 220 or 240 VAC operation. 3 Operation 3.
D-45 / D-75A Power Amplifiers The amplifier is switched between dual and bridgemono operation with the dual/mono jumper located inside the amplifier (see Appendix A). The unit’s input gain is 26 dB as determined by 1% precision resistors in the feedback loop. This can be changed to a sensitivity of 0.775 volts by following the instructions provided in Appendix A. 3.
D-45 / D-75A Power Amplifiers 4 Specifications Note: The following specifications apply to all units in dual mode with both channels driven into 8 ohm loads and an input sensitivity of 26 dB gain unless otherwise specified. Standard 1 kHz Power: This term refers to maximum average power in watts at 1 kHz with 0.1% THD. Full Bandwidth FTC Power: This term refers to standard FTC power in watts from 20 Hz to 20 kHz with 0.1% THD.
D-45 / D-75A Power Amplifiers Input Sensitivity: Configurable for 26 dB gain or 0.775 volt sensitivity (see Appendix A). Turn-On: Minimum thumps. Power-up is instantaneous with no program delay. Output Connector: Barrier block terminals and stereo headphone jack. The headphone output is unpadded, and in parallel with the main amplifier outputs. Construction Output Impedance: Less than 15 milliohms in series with less than 3 microhenries. DC Output Offset: 10 millivolts or less.
D-45 / D-75A Power Amplifiers Crown specifications are guaranteed for three years. In an effort to provide you with as much information as possible about the power-producing capabilities of your amplifier, we have created the following power matrix. The specifications found in these tables are for 120 VAC, 60 Hz North American units and are guaranteed for three years.
D-45 / D-75A Power Amplifiers 5 Service This unit has very sophisticated circuitry which should only be serviced by a fully trained technician. This is one reason why each unit bears the following label: CAUTION: To prevent electric shock, do not remove covers. No user serviceable parts inside. Refer servicing to a qualified technician. sent “UPS ground.” (If the unit is under warranty, you may send it C.O.D. for the cost of freight via UPS ground.) The factory will return it via UPS ground.
D-45 / D-75A Power Amplifiers Crown Factory Service Information Shipping Address: Crown International, Inc., Factory Service, Plant 2 SW, 1718 W. Mishawaka Rd.
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D-45 / D-75A Power Amplifiers Appendix A A.1 Internal Settings From the factory, your amplifier is configured for dual (stereo) operation and an input sensitivity of 26 dB gain. You may optionally configure the unit for higherpower, single-channel, bridge-mono operation. Also, the unit can optionally be set for an input sensitivity of 0.775 volts. To configure the unit for bridge-mono operation or 0.775 volt input sensitivity, the chassis of the unit must be opened.
D-45 / D-75A Power Amplifiers Some applications may require the gain structure to be calculated based on a sensitivity of 0.775 volts. And although the 26 dB gain setting provides a sensitivity for each amplifier that is very near 0.775 volts, the 0.775 volt sensitivity setting is provided for applications that demand this sensitivity with a high level of precision. A Crown Service Center or a technician in the field can activate the 0.775 volt input sensitivity without voiding the warranty.
