This circuit runs at low voltage, so everything is not as it first appears.
The first triode is grid-leak biased. A negative voltage develops at the grid due to grid current, and I would estimate a bias of about -50mV in this case. This might not sound like much, but with only 9V supply the valve will only have about 600mV total input headroom!
The second triode's grid is also negative because of grid current, and is probably around -0.1V in this case. These figure will vary a great deal with the actual valve plugged in, however, due to manufacturing variance. http://valvewizard.co.uk/Triodes_at_...s_Blencowe.pdf
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