I N T R O D U C T I O N

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 trans•nova 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 trans•nova (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.

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Hafler P7000 manual T R O D U C T I O N
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P7000 specifications

The Hafler P7000 is a professional power amplifier renowned for its robust performance and reliability in live sound and studio applications. A cornerstone of the Hafler brand, the P7000 embodies advanced technology and engineering, making it a popular choice among audio professionals.

One of the standout features of the P7000 is its high power output. It delivers up to 700 watts per channel at 4 ohms, providing ample headroom for demanding audio environments. This powerful output makes it suitable for driving large loudspeakers or multiple speaker systems, ensuring clear and dynamic sound reproduction even at high volumes.

The P7000 utilizes a class AB amplifier design, combining the benefits of class A and class B architecture. This design choice ensures low distortion levels while maintaining efficient operation. As a result, users can expect a warm and natural sound with low signal degradation, making the amplifier ideal for critical listening environments.

In terms of build quality, the Hafler P7000 is constructed with durability in mind. The chassis is made from robust materials that can withstand the rigors of frequent transport and use in various settings, from professional studios to live concert venues. Additionally, the amplifier features a well-ventilated design, minimizing overheating and ensuring reliability during extended operation.

The P7000 also includes advanced protection circuitry to safeguard against overload and short circuits. This feature not only protects the amplifier itself but also the connected speakers, providing peace of mind during high-energy performances. Furthermore, the amplifier incorporates a soft start circuit, which gradually ramps up power to the speakers, preventing sudden jolts that could cause speaker damage.

Connectivity is another key aspect of the Hafler P7000. It offers a variety of input options, including XLR and 1/4" TRS connectors, making it compatible with numerous audio sources and easy to integrate into any existing setup. Balanced inputs help reduce noise and interference, ensuring clean signal transfer over long cable runs.

With its combination of powerful output, reliable performance, and versatile connectivity, the Hafler P7000 stands out as a professional-grade amplifier. Whether used in a studio setting or live sound application, it provides audio professionals with the tools they need to achieve exceptional sound quality and consistency.
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