Ruby EL34 BHT's is what Bogner himself told me he's going to be putting them in all the new Shivas and more of his ams. I've heard nothing but good things about them. And as many know, the Chinese are steppin up their game on pickup making. Even the Shug's (Chinese) preamp tubes are sounding great now days, just might be why many boutique makers like Bogner, Freidman, and Splawn are using Chinese tubes it their expensive $2000-4000K amps. You can either order a couple sets from CE Dist. A
and find the best matched set, or order from Dougs Tubes, he's pretty much king of the best screened, tested, and reliable tubes from Ruby.