To Next PageTo Next PageWhy does my Crown K1 not meet power specs?
If your Crown Amplifier isn't reaching its specified power output, examine your power source. A drop in AC voltage below the amplifier's operational voltage can prevent it from reaching its full rated output.
What to do if my Crown K1 Amplifier gets extremely warm at idle?
If your Crown Amplifier is getting excessively warm when idle, check the Enable indicator on the front panel. If the amplifier doesn't enter Sleep Mode (indicated by half intensity of the Enable light) when there's no signal, the issue likely resides on the Input PWA. In that case, discharge the supplies and then inspect the Input PWA.
What to do if there is distortion in one or both channels with IOC indication in Crown K1?
If you're experiencing distortion in one or both channels of your Crown Amplifier, accompanied by an IOC indication, the problem most likely lies within either the Output PWA or the Main PWA. Begin by inspecting the Output PWA. If the Output PWA is functioning correctly, then repair or replace the Main PWA.
What to do if there is no signal with Enable light only in Crown Amplifier?
If your Crown Amplifier shows no signal but the Enable light is on, the issue probably stems from the Input PWA. If the Input PWA is not the problem, then the Main PWA is at fault.
How to resolve distortion with no IOC in Crown K1 Amplifier?
If you notice distortion in one or both channels of your Crown Amplifier without any IOC indication, the problem is most likely located on the Input PWA. First, check the levels on the affected channels with no load. If the levels are correct, discharge the supplies, and then repair or replace the Input PWA.
What to do if there is no signal with IOC on in Crown K1 Amplifier?
A constant IOC condition indicates a problem in the signal path including the Error Amp circuit. This includes the Main and Output PWAs. The problem most likely exists on the Main PWA.
General| Signal to Noise Ratio | > 100 dB |
|---|---|
| Total Harmonic Distortion | <0.05% |
| Input Sensitivity | 1.4V |
| Weight | 22 lbs (10 kg) |
| Channels | 2 |
| Input Impedance | 20 kOhms balanced, 10 kOhms unbalanced |
| Cooling | Convection cooled |
| Frequency Response | 20Hz - 20kHz |
| Dimensions | 19" x 3.5" x 11.5" (483 x 89 x 292 mm) |
Provides an overview of the K1 and K2 power amplifier service manual contents.
Describes the K Series amplifiers as efficient, compact, high-power audio amplifiers for professional use.
Outlines warranty policies and directs users to Crown Factory Service or Authorized Warranty Service Centers.
Explains the modular design and module exchange program for K Series amplifiers, emphasizing PWA replacement.
Details the steps for servicing K Series amplifiers, including PWA return and warranty claim procedures.
Details frequency response, output power, signal-to-noise ratio, voltage gain, damping factor, and line voltage requirements.
Describes the front panel level controls and rear panel switches for input sensitivity and operation.
Explains the function of the front panel LEDs: Thermal, Clip, IOC, Signal, and Enable.
Details input connectors, input stage, impedance, sensitivity, output connectors, and DC output offset.
Describes the stereo and bridge-mono output signal configurations.
Details general protection features and TLC protection circuitry for the amplifier.
Describes the chassis, cooling system, dimensions, and weight of the amplifier.
Describes the state-of-the-art 'soft start' feature that prevents large inrush current when turned on.
Explains the general operation of the K Series amplifier, covering Power Supplies, Input Stage, DC Servo, Sleep Circuit, Error Amp, and Modulator.
Details the main high energy power supply and low energy power supplies found within the K Series amplifiers.
Describes the AC line cord termination, fuse, AC line filter circuit, and path to the power transformer primary.
Explains how ±Vcc power supplies initiate and power up the 125KHz oscillator and gate driver.
Details input connectors, signal path, impedance, and input sensitivity selections.
Explains the DC correction circuit added to compensate for DC offset voltages that can appear.
Describes how the sleep circuit monitors for signals and sends a Standby signal to the main module.
Explains how audio signal and negative feedback signals are processed by the error amplifier.
Details high speed differential comparators used in the modulator circuit and their balanced output.
Explains the origin of the 250KHz triangle wave and its journey through various stages.
Describes the generator that outputs a DC voltage varying with ±Vcc levels to influence the 250KHz output level.
Details how the modulated 250KHz signal enters the output assembly via U02 and U52.
Explains the output filter consisting of three individual filters to eliminate residual signals.
Describes how audio output current levels are monitored by transformer T100.
To prevent excessive output current, the K series amplifiers are incorporated with a current limiting protection circuit.
Explains how the Overlap adjustment corrects for DC shift in the Triangle waveform using a potentiometer.
Describes the IOC (Input Output Comparator) circuit and its function with error signals.
Details the functions that can disable the modulator circuit and disable the amplifier.
Explains the DC protection comparator circuitry and how it latches the fault circuit.
Details how the K Series amplifier can be configured to operate at any line voltage worldwide.
Outlines the three basic steps for effective repair: determine symptom, identify cause, and repair unit.
Explains that the extent of disassembly required depends on the inspection and service needed.
Provides step-by-step instructions for removing the bottom cover of the amplifier.
Details the procedure for safely discharging the power supplies before disassembly.
Explains how to remove the back panel assembly to access the Input and Main PWAs.
Provides instructions for removing the front panel assembly to access specific components.
Details the steps for removing the Input PWA after the back panel assembly is removed.
Explains how to remove the Main PWA after the back panel assembly is removed.
Provides instructions for removing the left and right Output PWAs.
Details the steps for removing the Control PWA.
Explains how to remove the Line Filter PWA for early non-CE units.
Details how to remove the Power Transformer, which requires front panel removal.
Explains how to remove the Display PWA after the front panel assembly is removed.
Details how to remove the Bridge PWA after the front panel assembly is removed.
Guides the technician on how to identify and verify amplifier symptoms, including intermittent issues.
Outlines the process of visual inspection, using spare PWAs, and checking voltages to identify faults.
Lists essential test equipment and recommended models for servicing the K Series amplifier.
Details various electrical checkout procedures to verify amplifier operation and troubleshoot problems.
Specifies and describes the procedure for measuring the amplifier's quiescent AC power draw.
Details the specifications and procedures for testing the 1.4V and 26dB gain switch settings.
Describes the procedure to test the 'Y' input switch for proper operation and phase alignment.
Details the procedure to test the bridge mono switch for proper voltage and phase.
Specifies and describes the procedure for measuring the amplifier's frequency response.
Details the procedure to test the amplifier's short circuit protection.
Specifies and describes the procedure for measuring the output power for K1 and K2 models.
Specifies and describes the procedure for measuring intermodulation distortion.
Specifies and describes the procedure for measuring the signal-to-noise ratio.
Specifies and describes the procedure for measuring crosstalk at 1 kHz.
Details the factory default settings to return the amplifier controls to after testing.
Provides procedures for calibrating the Gaussian filter and adjusting overlap correction.
Provides procedures for calibrating the Gaussian filter using a multimeter.
Details the procedure for adjusting overlap correction on the output assembly.
This chapter includes mechanical and electrical parts lists. All serviceable parts have a Crown Part Number (CPN).
Provides guidance on ordering parts, including product model, description, and part number.
This chapter includes a mechanical part list. All serviceable parts and assemblies will have a Crown Part Number (CPN).
Lists major parts of the main chassis with descriptions, part numbers, quantities, and notes.
Provides an exploded view and parts list for the front panel assembly.
Lists parts for the back panel assembly, including PWAs, connectors, and screws.
Introduces updates and revisions to K Series amplifiers and lists all modules used as of printing.
Lists Main PWAs with their part numbers and corresponding PWB revisions.
Lists Input PWAs for K1 and K2 models, including part numbers and revisions.
Lists Output PWAs and recommends ordering complete Output Assemblies.
Lists Control PWAs with their part numbers and associated PWB revisions.
Lists Bridge Rectifier PWAs with part numbers and revisions.
Lists Display PWAs with part numbers and revisions.
Lists Line Filter PWAs with part numbers and revisions.
Provides references to schematic diagrams for various PWAs, including revision letters.
This chapter includes electrical parts lists for this product. All serviceable parts and assemblies will have a Crown Part Number (CPN).
