Hafler trans*nova P1500 Professional Power Amplifier, made in USA



The Hafler P1500 and P3000 are two channel professional power amplifiers. Passive cooling with large heatsinks is used for low mechanical noise. Our patented trans•nova circuit topology and MOSFET output stage ensures trouble free, long term operation and is backed by our five year warranty. This manual contains information on using the P1500 and P3000 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 an explanation of circuit operation 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 P1500 and P3000 is the latest refinement of our trans•nova (TRANSconductance NOdal Voltage Amplifier, US Patent 4,467,288) circuit. It has been proven to offer sound quality to satisfy the most analytic audiophile or the most demanding professional. The natural sound and realistic reproduction have made trans•nova amplifiers preferred in many critical installations. Since our pioneering use of MOSFETs in the DH- 200 amplifier, they have proven extremely fault tolerant even in abusive situations. This sturdiness enables the amplifier to drive reactive speaker loads without the performance and sound penalties imposed by elaborate protection schemes. 

Specialized circuits prevent damage to the amplifiers and speakers without 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 from excessive operating heat. The need for internal fuses has been eliminated; a sensing circuit monitors the output and shuts down operation when it detects a short in the output load.

Each channel of these amplifiers is built as a self-contained module which only requires mounting the heatsink and connection to the chassis-mounted transformer and binding posts to be fully functional. The circuit board contains all the operational components. 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.


внимание: проведена профилактика в виде замены 4-х smd конденсаторов










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.


Frequency Response:
  • 20Hz to 20kHz, ±0.1dB
  • 0.15Hz to 300kHz, +0/–3dB

Signal-to-Noise: 
>100dB “A” Weighted

Distortion: <0.2% 20-20kHz, typically .01% at 1kHz @ rated power into 8Ω 
Slew Rate: 100 V/μs
CMRR: 75dB at 1kHz
Input Impedance: 47k ohms per phase
Gain: 
  • +14dB min.
  • +29dB max. 
Power Rating:  75 wpc @8 Ω, 85 wpc @ 4Ω, 170 Watts mono @ 8Ω 
Damping Factor: 350 (to 1kHz); 150 (to 10kHz); 18 (to 100kHz) 
Input Sensitivity Range: 
  • 870mV - 4.8V (for 75 W @ 8Ω)
  • 650mV - 3.7V (for 85 W @ 4Ω) 

Power Consumption: 
60W / 500mA @ 120 VAC (Idle Power) 
230W / 1.9A @ 120 VAC (1/8 Power – 8Ω) 
325W / 2.70A @ 120 VAC (Max. Power – 8Ω) 

Dimensions: 
19"W x 8-1⁄2"D x 3-1⁄2"H (2-rack spaces) (48.26cm x 21.59cm x 8.89cm)

Net Weight: 

22 lbs. (9.98kg)