ECL805 push pull amplifier test

Here my try out and test board is shown.
I've just finished the measurements and design of this amplifier which features grid bias for higher output power.
This push pull amplifier is able to produce up to 15 watts of output power before clipping.
In the end of the video I play with the amount of grid bias. The tubes are somewhat matched for similar current flow in each one.
The amplifier uses a B+ of 275 volts, with a grid bias of minus 33 volts. The anode current while idle is 26 mA. The triode in the tube on the left is the driver and triode on the right is the phase splitter.
It operates in ultra linear mode without global feedback.
The loudspeaker here is a Harbeth HL-P3
Music: Glidepath, by SPMC