David Hafler DH-120 Power Amp 120W amplifier

120W solid state power amp, 60W per channel. MOFSET class AB linear power amplifier.

Some deep reading:

https://www.kenrockwell.com/audio/hafler/dh-120.htm

https://eiaudio.de/gear-and-review/power-amplifiers/hafler-dh-120/

(Due to people taking advantage of eBay / Reverb return policies; wanting to “try out and/or pilfer parts” we can no longer take returns on used gear unless it arrives damaged. Sorry for this inconvenience. We test and guarantee all gear to be 100% working unless stated otherwise.)

Come play it in our shop!

Specifications

• Power output (RMS, 8 ohms): 2 x 60 watts
• Transistor Type: Hitachi Mosfet
• Frequency response (60 watts, +/-0.5 dB): 10 – 40,000 Hz
• Frequency response (1 watt, -3 dB): 4 – 200,000 Hz
• Signal to noise ratio: >100 dB
• Damping factor: 100:1
• Crosstalk: 85 dB
• Rise time: 2 uS
• Weight: 9 Kg
• Year: 1984 – 1990

Output Power

Stereo

Less than 0.009% THD at any power level up to 60 watts per channel, both channels driven, from 20-20,000 Hz.

 

Mono (one channel only)

150 watts into 8Ω.

 

Audio Input

One stereo pair of 1/4″ RCA jacks with individual potentiometers.

22 kΩ.

1.1 V RMS input for 60 watts into 8Ω.

 

Audio Output Connectors

Standard 5-way binding posts on standard 3/4″ centers.

Total four pairs or 8 posts.

 

SMPTE Intermodulation Distortion

< 0.005% from 1 – 60 watts into 8Ω.

 

THD at 60 WPC into 8Ω (typical)

20 Hz: 0.002%

1 kHz: 0.002%

20 kHz: 0.006%

 

Frequency Response into 8Ω

10 – 40,000 Hz at 60 watts, +0, -0.5 dB.

4 – 200,000 Hz at -3 dB at 1 watt.

 

Crosstalk

> 75 dB at 20 Hz.

> 85 dB at 1 kHz.

> 65 dB at 20 kHz.

 

Signal to Noise Ratio

>100 dB unweighted, referred to 60 watts.

This means < -82.2 dBW or < 219 µV or < -73.2 dBV noise output.

 

Damping Factor

100 at up to 1 kHz into 8Ω.

50 at up to 10 kHz into 8Ω.

 

Rise Time

2 µS from 10% to 90% with a 45 V p-p 10 kHz square wave.

 

Slew Rate

30 V/µS with a 45 V p-p 10 kHz square wave.

 

Semiconductors

4 power MOSFETs: one pair of complementary Hitachi 2SK134 and 2SJ49 lateral MOSFETs per channel.

Each of these power MOSFETs was individually tested, graded and sorted by Hafler. Each was stamped with a number from one to five and assembled accordingly into amplifier modules.

22 transistors.

23 diodes.

8 Zener diodes.

1 bridge rectifier.

 

Power Input

120 VAC, 60 Hz.

Rated 480 W maximum.

Actual power consumption is much less.

 

Quality

Made in the United States of America (Pennsauken, New Jersey).