Photos on construction progress
Tube characteristics using uTracer
Modeling using LTSpice and the extracted models
Notes on cathode resistors and bypassing in push-pull designs
Experiments with power supply
Examples of measurements at the 8Ohm outputs showing the switching diodes in the power supply, without snubbers on the secondary and with a 10nF+1kOhm snubber, respectively.
Using slugging 10nF capacitors parallel to UF4007 diodes created more ringing (which agrees with this, saying that fast-switching diodes should not be paralleled with capacitors).
A bit more about snubber can be found here. Some extra plots:
Testing the Lead-RC network
Testing the open loop connecting with a RC-lead network for different C, with R=39kOhm. Examples of Left and Right channels in open-loop configuration, and the frequency responses for (blue) no lead-network, (yellow) C=82pf, (green) C=100pf, (red) C=200pf: