Valve preamp.

[Kalee20]

... for instance the sycamore wooden box was planed down from rough 1 1/2" boards straight off the tree, took me ages with a small hand plane especially the 45 deg mitre's.

Nice work, especially as there's a couple of knots in the wood! Adds to the final appearance, but harder work to get there.

I like marrying electronics with dead plants.

Cathode follower outputs to drive cables is a good move.