Hafler-P7000-pwr-sm维修电路原理图.pdf

PROFESSIONAL POWER AMPLIFIER P7000 Installation 200 (to 10kHz); 25 (to 100kHz) Power Consumption: 275 VA quiescent. 1440 VA with both channels driven at 350 watts at 8, 1800 VA maximum. Controls 100Hz as supplied Indicators:Power lamp, Clip, Short, Thermal, Signal LEDs Connectors:Input:2-way XLR and 1/4 Tip Ring Sleeve Output: 5-way binding posts spaced for dual banana plugs Power:IEC 320 Dimensions:19W x 1278D x 312H plus 118 for handles, includes rear supports (48.3cm x 32.7cm x 8.3cm plus 2.875cm for handles, includes rear supports) Net Weight:40 lbs. (18.18kg) ii RadioFans.CN 收音机爱 好者资料库 TA B L E O F CO N T E N T S SAFETY PRECAUTIONS. i PERFORMANCE SPECIFICATIONS. ii INTRODUCTION. 1 INSTALLATION Location . 2 AC Line . 2 Input. 2 Input Crossover . 3 Input Mode Switches . 3 Output Connections . 3 OPERATION Power Switch . 4 Level Controls . 4 XCard Crossovers . 4 Ground Switch . 5 Short Circuit Protection . 5 LED Indicators . 5 Warm Up . 5 Cleaning and Maintenance. 5 TECHNICAL REFERENCE Field Service Considerations. 6 Theory and Operation of transnova .6 PC Board Layout. 7 Schematic Diagram . 8 Parts List . 10 P7000 Functional Block Diagram . 12 Circuit Operation . 13 Amplifier Module Replacement . 16 Building Custom XCards. 17 Resistor Chart . 18 WARRANTY . 19 RadioFans.CN 收音机爱 好者资料库 IN T R O D U C T I O N 1 The Hafler P7000 is a two channel professional power amplifier suitable for use in any sound reinforcement situation where faithful, accurate reproduction is required. The amplifier uses forced air fan cooling to deliver high power output in a compact size. Status indicators on the front panel give a visual representation of amplifier and system operation. Input configuration switching and active crossovers enhance the flexibility when used in multiple amp systems, without requiring the use of additional equipment. The use of our patented transnova circuit topology and MOSFET output stage ensures reliable, long term operation which is backed by our five year warranty. This manual contains information on using the P7000 amplifiers. It is organized into three main sections. “Installation” covers the location and connection of the amplifier in the system. Like many precision components, careful attention to the initial setup can yield dividends in higher performance and trouble-free use. “Operation” covers the controls and features of the amplifiers and how to use them to get the best effect. The “Technical Reference” section contains field service information; in addition to the schematic and parts list there are block diagrams and circuit operation explanations useful for technicians. We strongly urge reading over the Installation and Operation portions of this manual before putting the amplifier into service. The circuitry used in the Hafler Professional power amplifiers is our transnova (TRANSconductance NOdal Voltage Amplifier, US Patent 4,467,288) circuit. The P7000 also utilizes our proprietary DIABLO (Dynamically Invariant AB Linear Operation, patent application in progress) transconductance driver stage which combines the linearity of Class A operation with the current headroom of a Class B system. When combined with the robust output stage used in the P7000, DIABLO yields lower high frequency distortion without the sonic penalties associated with increasing the negative feedback. We have been using MOSFETs in our power amplifiers since the 1970s. During this time, they proved to be extremely fault tolerant, even in abusive situations. This ruggedness enables the amplifier to drive reactive speaker loads without the performance and sound penalties imposed by elaborate Safe Operating Area protection schemes. Active crossovers are incorporated at the input of the amplifier. These crossovers are controlled through the use of our XCard plug-in modules. Each XCard can operate as a full-range, high-pass or low-pass filter with a 12dB per octave Butterworth alignment. Each channel utilizes two XCards which in combination can be configured as a 24dB per octave slope or a 12dB per octave bandpass filter. Since the XCard contains the resistors and capacitors that establish the crossover Q and frequency; specific system requirements can easily be accommodated just by changing the component values. Input configuration switches allow the amplifier to be configured for conventional stereo, two channel mono or single channel bridged use. When the amplifier is run in two-channel mono mode, the level controls and crossovers for each channel are fully functional which allows for using the amplifier as a single channel in a bi-amped system. Specialized circuits which prevent damage to the amplifiers and speakers have been carefully implemented to avoid affecting the audio signal. A soft start circuit prevents sending potentially destructive turn-on and turn- off transients to the speakers. A thermal sensing network monitors the heatsink temperature and shuts down the amplifier to protect it from excessive operating heat. The need for internal fuses has been eliminated; a sensing circuit monitors the output and shuts down the power when it detects a short in the output load. Each channel of the amplifier has been built as a self-contained module. This modular arrangement simplifies construction and improves service accessibility. The circuit board assembly makes extensive use of surface mount components in the low power portion of the audio circuitry. Automated equipment is used to place and solder the components which yields greater uniformity and reliability. The front panel has controls for input level adjustment and the power switch. In addition, LED indicators give a visual representation of the operating status of each channel. The THERMAL and SHORT indicators light to show when these protection circuits have been activated. The clip indicator helps prevent damaging the speakers by showing when the amplifier is overdriven. The SIGNAL indicator lights to show the presence of an audio signal. RadioFans.CN 收音机爱 好者资料库 IN S T A L L A T I O N LOCATION The P7000 uses forced-air fan cooling to remove the heat produced in normal operation. Although this makes the amplifier less sensitive to ventilation than if it were passively cooled, fresh air flow at the mounting location must still be considered. The fan pulls in fresh air through the side vents and the heated air is forced out through the front panel. Another consideration when choosing the location for a fan cooled amplifier is its proximity to the listening position. In some situations the sound of the fan operation can be distracting. The power transformer can generate a substantial magnetic field, so caution should be exercised in the placement of low level components such as a tape deck, mixer or mic preamp to avoid inducing noise in the low level circuitry. Allow several inches of clearance when mounting these components. AC LINE The P7000 operates from a 120 volt, 60Hz AC power line. Connection is made by 14 gauge, IEC Type 320, grounded line cord. For safety considerations only a properly grounded (earthed) receptacle should be used. If a grounded circuit is not available do not break off the ground pin; use the proper adapter plug for a two wire receptacle. The power line fuse is mounted on the rear panel of the amplifier. If this fuse blows replace it only with the same type and rating fuse. The correct replacement fuse value is printed on the rear of the amplifier and in the parts list. INPUT The input jacks used on the P7000 are dual function connectors which accept 1/4 (Tip Ring Sleeve) phone and XLR plugs. The amplifier will operate with either a balanced or unbalanced signal source. The connector pin- out is printed on the rear panel of the amplifier. Balanced Input: 1/4 Tip Ring Sleeve The 1/4 balanced input jack is connected according to conventional usage with the Tip high (+), Ring return () and the Sleeve ground shield. Balanced Input: XLR The XLR balanced input jack is connected according to the IEC and AES Standard, with pin 2 high (+), pin 3 return () and pin 1 ground shield. When preparing to use the amplifier, check the output configuration of the source unit to maintain the proper signal polarity. Unbalanced Input Many popular mixers use unbalanced RCA phono or 1/4 phone jacks for the monitor outputs and can be used with the P7000 for short cable runs. The specifications for the mixer should give the maximum cable length it is capable of driving. The return () terminal must be grounded when using the amplifier with the input unbalanced to prevent unstable operation. Unbalanced Source with Balanced Input Some systems will have a noticeable amount of residual ground noise when run with unbalanced signal lines. Better noise rejection can be achieved in these systems by using shielded, twisted pair (balanced) cable from the unbalanced source. At the source end of the cable, connect an RCA or 1/4 phone plug with the return () wire and shield connected to the ground terminal of the plug. Wire the plug at the amplifier end of the cable the same as for the regular balanced input connection described above. 2 RadioFans.CN 收音机爱 好者资料库 3 INPUT CROSSOVER The XCard crossover modules are plug-in cards located inside the amplifier. The P7000 is shipped with 100Hz XCards in each channel. Since each XCard can operate full range, high-pass or low-pass, with a 12dB per octave slope, this allows the amplifier to be used in a wide range of applications. XCards are available for a variety of frequencies from your dealer or through our Customer Service department. To order additional XCards call Customer Service at 800-669-9899. Office hours are 8:00 a.m. to 5:00 p.m. MST, Monday through Friday. All orders are pre-paid and VISA and MasterCard are accepted. INPUT MODE SWITCHES Two-Channel Stereo To run the P7000 in two-channel mode, set the front channel NORMAL/BRIDGED switch in the NORMAL position and set the rear panel STEREO/BI-AMP switch to the STEREO position. This configures the amplifier for conventional left and right stereo operation. Dual Mono The rear panel STEREO/BI-AMP switch configures the input connection required by the amplifier. With the switch set for STEREO Channel 1 and Channel 2 require separate input signal source feeds. When the switch is set for BI-AMP the Channel 1 input feeds the signal to both amplifier channels for dual-mono operation. The level control and XCard for each channel are still active. Bridged Mono In systems with higher power requirements, the P7000 can be configured for signal channel, bridged mono operation. To bridge the amplifier, set the front panel NORMAL/BRIDGED switch to the BRIDGED position. Only the Channel 1 input and level control is used and the Channel 2 level control and XCard are not active. The speaker is connected to the RED output binding posts. When the amplifier is bridged, the output is floating. Any speaker which requires a common ground from the amplifier output cannot be used in this application. Since a bridged amplifier shares the load between the two channels, each channel will effecti