• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Harmon Kardon Galaxy BA-150


2008-04-10 3:52 pm
I have recently acquired a pair (yes, a pair) of Harmon Kardon Galaxy BA-150 amps. These are monsters, rated at 150 W, driven by a quad of 6550's. Does anybody have experience rebuilding these units? I have roughed out a schematic, but could find nothing else available. In looking over the amplifiers, I am disappointed by the quality of the point-to-point wiring. I do plan to replace the 6550 sockets with vector sockets, which will help to clean up the wiring quite a bit without making basic circuit modifications. Of corse, the usual power supply upgrades are also in order. I am open to any suggestions.


2014-07-18 9:57 pm
HK BA-150 amps

Some one just brought me 5 yes 5 of these amps to restore.
How did yours turn out?


  • image.jpg
    713.1 KB · Views: 84