A 12B4 driver transformer coupled will do the job, but a little B9A 12B4 looks
dreadfully weedy against a DA100. (Or an 845)

A 12b4 has a mu of 6.5 - surely you need more gain than this with a 1:1
interstage? Or are you running it low voltage? Interestingly the low voltage
curves for the 845 look just like the KT66. I have a pile of 12b4 but I have to
say that my favourite input valve these days is a 7913 (2c22). I have quite a
few if you want to try it - it's extremely detailed with very nice high treble.
It's kind of a 6J5G/6P5G but it's even better than those. Andy

=== Andy Evans ===
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