ECL805 push pull integrated amplifier build

This is a 12 watts per channel stereo push pull amplifier which features 3 line inputs for direct connection of a line source. The build has been finished recently but only now I have taken the time to make a video about it which shows the build and more information. It operates in ultra linear mode without any feedback. The tubes are grid biased and adjusted to 27mA for each tube separately. When tubes are swapped, the amp needs to be adjusted again. This can be done on the inside, terminals for measurements are provided and adjustment is done with a potentiometer for each tube. The schematic is a straightforward design which is kept simple and safe, nothing fancy but it performs well. The power transformer is custom made.
It uses a cathodyne phase inverter and a sensitive driver. Heaters are grounded using a voltage divider from the B+, which is 280V.
The ECL805 (6GV8) is a very robust and capable tube which is surprisingly suited for audio: sensitive triode section and small pentode which lets current flow at lower voltages, I like this tube a lot.
Schematics are at the end of the video.

The sound in this video came from this actual amplifier and is recorded separately and later synchronized with the video. Loudspeakers used here: Rogers ls3/5a.

If you're trying to build this amplifier you're doing so at your own risk, knowledge of working with vacuum tubes is a must since the voltages in this amplifier are dangerously high... but that accounts for almost any vacuum tube device. This also applies to all of my videos ;)

Music: 'Versatile' by Plug.
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