2x40w valve amp missing transistor identification (bias)

[kenneth]

Hello! I want to build a EL84 PP amp. I found only one circuit suitable to use with my Dem-Technic 3,4k opt.
Unfortunately one transistor in the bias circuit schematic (attached) doesnt have a identication.
Maybe someone here can help out. Regards

 

[kodabmx]

I think the fact it's unmarked means basically any old NPN transistor would work.
2N3904 maybe? MPSA42 if the voltage rating needs to be higher?

OTOH, you could just use TL783 or the like as the CCS for a simpler solution.