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Dominik,

I do not think that you need suggestion from me. If Pieter looked at the schema then everything is very much identifiable in there and he shall know what to do. Let me to give you alternatives that are not at the schema.

The 12,6V/5A, 6,3V/1A filament transformer might be as proposed but it might be also just simple 6,3V transformer with 8-10A secondary. You see, the 6C33C has two pair of heated and you might connect them in series or in parallel. There are many debases what is better, both camps have own reasonable arguments. I made the experiment and I was not able to hear difference between series or in parallel. I had 12V because I would like to keep current down (six driver filaments and six 6C33C filaments, each of 6C33C them 6A) but in your case what you have one 6C33C per amps you might stay with 6.3V only and use parallel heaters. The benefit of the parallel heaters that is you have good speakers that do not need a lot of power then you will be able to disconnect one heater and use just one anode of 6C33C – it will sound better….

The bias and the B+ for the first stage are fine.

The power supply chokes need to be warned. I do not know how Pieter does his chokes but some of the chokes do not work well in input choke application as they are too “loose”, not well varnished perhaps and in input choke application they have noise  - something that I hate very much. Explain to Pieter that the chokes will be work right after rectifiers and will see very high ripples. So, the chokes need to be made that they would not buzz. Pieter or whoever will do it will knows what to… Ironically the very cheap Hammond chokes are very well made from the perspective of “none-buzzing” in input choke application. They have even a custom version for each choke (10% more expensive) where they double-dip choke in epoxy (separate coil and separate assembled choice). They look ugly but you can drive the Hoover Dam currant across them and they still will be silent.

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