• 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.

My "Stupendous" PPP 6P1P build


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I used SMPS in Gubernator-71 amp, to power filaments of GK-71 tubes. The SMPS was rated properly for hot filaments, but could not start. So I used 12.6V winding from the transformer, and with a diode bridge connected it in parallel to filaments. The problem solved! 12.6V rectified heated up filaments, their temperature increased, resistance increased, then SMPS started and took over!
Feet glued to chassis. Feet made from "Action" broomstick. Bezemsteel | Action.com 94 eurocents. Won't get a "dowel" for that price from your local builders supply.:)

Boards also completed and cleaned. Now just waiting for the power transformers to arrive. Before I start mocking it up.


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Hi Bas,

looks great so far!
Thanks for the idea of bamboo box shelves.
I might have to try this in the future, too.

I am very comfortable with metal working. I also like working with wood in principal, but I am usually not very happy with the result at the end. Last chassis took me many weeks of painting, sanding, painting, sanding, polishing, painting, sanding, polishing...(I think you get it).
Only finally I was kind of happy with the result.

I am very comfortable with metal working
Hi Martin,

To me it is a chore. Things have gotten better with my age and experience as I have more patience. But again I made and error with my 2a3 amp top chassis. Drilled one hole in the wrong place. But luckily I will probably be able to mask it with a big washer of some sort. Not so much a chore as it is daunting...I'm always holding off starting. That's why I love wood...its much more forgiving.

Kind regards,