Hewlett Packard 6K6 Stereo Tube Amp

[HotBluePlates]

Looks like HP made at least one tube stereo back in the day. The tubes are probably original, and date from '67, making me think the rack case was borrowed from one of their pieces of test gear.

I know I've seen some documentation on a solid-state stereo that some of the engineers made for a small handful of employees; this may have been the precursor.

[DummyLoad]

it would be nice to have a look see at a schematic of that amp.

--DL

[FYL]

The silicon amp was a project launched by the late Bernard Oliver. Check http://www.hpmemory.org/news/barney_ampl/barney_page_00.htm for more info.

[HotBluePlates]

it would be nice to have a look see at a schematic of that amp.

--DL

Well, the pics are in the original fleabay listing. I figured interested parties would follow the link and check it out for themselves.

Unfortunately, a schematic would likely have to be drawn by the owner of the 6K6 stereo. And push-pull 6K6's?? I'm guessing the designer had a horn-loaded setup at home... Or at least some very efficient speakers.

The silicon amp was a project launched by the late Bernard Oliver. Check http://www.hpmemory.org/news/barney_ampl/barney_page_00.htm for more info.

Yep, the "Barney Oliver amp" was the one I was thinking of.

[PRR]

P-P 6K6 is the H-P 200AB oscillator's output stage.

6V6 was available when the 200AB was designed; I never really wondered why they used the older tube.

[HotBluePlates]

Good point!

But the 200AB is rated for 1w output in 600 ohms. HP did, however, use a much smaller OT in the 200AB.