[quote author=mullman link=1142366672/0#1 date=1142368954]Someone had one of those, or maybe a Sophia?
Randy? [/quote]
Yep ..... I have both, actually 3 ..... an early production Valve Art, a Sophia solid plate and a Sophia mesh plate.
According to the spec sheet for a 274B, a Zen Select has too much capacitance to make this rectifier happy. It likes to see a lot less than the 40uf in the Select. Even so, there are quite a few Select owners that have used a 274B with absolutely no problems ..... myself included. It has been stated that the tube life might be shortened in a Select.
As to a Zen C, I don't remember reading anything about how well (or not) this would work ..... ???
The thread that originally discussed this was
Rectifier tube insanity .....Randy