I'm not qualified to interpret that schematic, perhaps noromance or someone else will chime in.
If anything it's going to be just a pair(L/R), not all 4 that will make a noticeable SQ difference? You can always just experiment when you get it. You'll be out just two pricey tubes instead of 4.
If anything it's going to be just a pair(L/R), not all 4 that will make a noticeable SQ difference? You can always just experiment when you get it. You'll be out just two pricey tubes instead of 4.