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Hafler DH-500

Stereo Power Amplifier Kit (1988)

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Hafler DH-500


Power output: 255 watts per channel into 8Ω (stereo)

Frequency response: 5Hz to 40kHz

Total harmonic distortion: 0.025%

Damping factor: 60

Input sensitivity: 2.35V

Signal to noise ratio: 100dB

Semiconductors: 27 x transistors, 12 x MOSfet, 33 x diodes, 8 x zener diodes, 1 x IC, 1 x diode bridge

Dimensions: 7.25 x 19 x 13 inches

Weight: 45lbs


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Reviewed Aug 22nd, 2013 by adlpc

An amazing and highly underrated (even forgotten) amplifier. Built like a tank with overall good quality components, but sadly with sub-par wiring. It does have more than sufficient power to drive almost any load and is modifiable to accept most inputs.
Sadly due to cost constraints, Hafler used cheap 18 AWG stranded wires in the input and output signal circuits. Run (don't walk) and replace the internal signal input wires with RU-6 coax (will silence background noise) and all other amp board wires with larger guage (12-14) solid wire (all these are cheap hardware stuff and work great!). Upgrading the power supply wires doesn't hurt either! Clean out the dust and the fan/heat sink while you're there for quiter fan operation too.
This amp can rival some of the current best esoteric designs with this simple and inexpensive upgrade.
This amp is a rock solid work horse and mine has sustained much abuse and has never missed a beat.




Thank you. I loaned my out...

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