Stereo Power Amplifier Kit
Power output: 100 watts per channel into 8Ω (stereo)
Frequency response: 10Hz to 40kHz
Total harmonic distortion: 0.012%
Damping factor: 50
Input sensitivity: 1.5V
Signal to noise ratio: 100dB
Semiconductors: 26 x transistors, 8 x MOSfet, 24 x diodes, 4 x zener diodes, 1 x diode bridge
Dimensions: 5-1/8 x 16 x 10-1/2 inches
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Reviewed Dec 20th, 2015 by uzzy
I have had mine since 1979 .. I have since bought another just in case any of the output Mosfets go as the original Hitachi ones are getting very rare.
Plug it in and forget about it .. match it to the highest possible quality pre-amp you can afford (I use an Audio Research SP9) and just enjoy .. it has dynamics and detail in spades and if I lost mine I would be heart broken ..
Have tried many amplifiers over the years (including: Nakamichi, NAIM, Mark Levinson, Lux and EAR) but the Hafler is to me unbeatable for its overall performance ... I had a minor repair done by ex Naim engineer (i knocked off one of the transistors from the circuit board when changing the RCAs to gold ones) .. he was a bit dumfounded I think at how well this amp performs remarking nice amp when i picked it up after the repair.
It will drive below 4 ohms (e.g. Gale 401s and KEF 104/2 etc.) with ease. Gordon King in HiFi News and Record Review said it was the finest amp he had heard but it was of course rubbished in other HiFi Mags where the world began and ended with Linn/NAIM.
If you can find a good working example buy it - for the Â£200 (average second hand cost) it will cost you, you can then sit back with a big smile realising you will have to pay over 5 times more for something to get close to it or equal it .. and unlike a lot of other amps do not worry about the impedance of your loudspeakers this baby works down to 2 ohms with panache ..
if you were to take the insides and put it in a nice fancy solid aluminium case perhaps it would be taken more seriously .. a wonderful amplifier unequaled in its price range and well above ...
Reviewed Jan 29th, 2015 by Sealtest
Very nice amp with many upgrade options. This amp is also very affordable compared to other amps which perform about the same.
Reviewed May 19th, 2014 by megranat
A gutsy, revealing, very dynamic stereo, dual MOSFET power amplifier, suitable for driving the best made and positioned loudspeakers that you can muster (with input from the cleanest sources only or you will cower behind the couch at the nasties it exposes). Typical of all early David Hafler amplifiers (pre and power) this was mainly sold in kit form, so open the lid and check that yours has been built properly with high quality components and properly soldered connections. These units are getting on now but, when I had mine in the late 1980s, with its matching (but modified to my requirements with miltary spec capacitors, the balance control bypassed and a crackle-free Teflon volume pot) DH-101 preamplifier, driving a pair of sensational Stig Carlsson OA-51 two way loudspeakers placed against the wall, on timber stands (see http://www.carlssonplanet.com/oa51.php for info) the results were spine-tingling. If you can get your hands on that kind of setup, enjoy and treasure. A classic 100Wpc power amplifier that I still regret selling, along with its associated gear to help pay for my first house!