As Stuart notes, the circuit concepts in this book integrate several ideas in a synergistic way, yielding an amplifier with very good performance. Menno has done a nice job of explaining these circuit tricks, done in the form of a meandering design path to get to the right answer, experimentally verified. The cost/benefit ($35/100 pages) is an individual decision, but Stuart is quite happy having read it, admitting it got him thinking about a few alternative approaches.
Vanderveen Trans Tube Amplifiers – Menno Vandeveen. Publisher: Elektor; ISBN: 978-1-907920-34-9, Elektor price: € 29.95; also available in German and Dutch.