I would like to build a new amplifier, this time with classic tubes references.

I wonder if I have drawn the see saw / paraphase inverter correctly?

Maybe a little bit of gNFB will be needed, in this case is it better to remove local feedback between ECC82 and EL34?

I didn't find max value of Rg1 for EL34 in fixed bias mode, 80-100K is fine?

OPT is 4.2K / 8 ohms with 2 & 4 ohms too (Quicksilver), maybe I'll use 4 ohms tap with 8 ohms speakers for better damping and easier life of EL34's. 20W is more than enough for my use.

Do you see errors on this schematic?

Thank you.

I wonder if I have drawn the see saw / paraphase inverter correctly?

Maybe a little bit of gNFB will be needed, in this case is it better to remove local feedback between ECC82 and EL34?

I didn't find max value of Rg1 for EL34 in fixed bias mode, 80-100K is fine?

OPT is 4.2K / 8 ohms with 2 & 4 ohms too (Quicksilver), maybe I'll use 4 ohms tap with 8 ohms speakers for better damping and easier life of EL34's. 20W is more than enough for my use.

Do you see errors on this schematic?

Thank you.