Rich,
Both the good and 'bad' tubes are the CV181. Don had sent out a newly finished preamp with matched tubes just days before mine was ready. He didn't have other matched sets sitting around, so he sold me two good, and two used tubes that were sitting in a drawer. These two used tubes are the ones he referred to as subpar. As soon as he receives new tubes, he will mail the new tubes to me. He said that one of my tubes is slightly microphonic, but I'll be damned if I can hear it. I think Jay didn't notice it either.
His sales volume is low enough that he typically buys just 5 pairs of tubes at a time. Same goes for cabinets, caps, transformers, etc. He does not have a roomful of parts just waiting for the next 20 orders. It was hard for me to imagine that because this puts him at the mercy of holiday delays, supplier hiccups, bad weather, etc. I'm obviously not in his shoes, but if it were my business, I'd prefer to keep five to ten units' worth of parts in stock. [I understand that is a lot of money to tie up.]
At this point my preamp has fewer than 40 hours on it.
I am very curious about how Don's KT-88 amp, Bob Latino's VTA ST-120, or other similar amps sound compared to my 400R. Sure, I heard Don's a week ago, but my aural memory just ain't that good. I may buy an ST-120.
