To Garrett Hongo,
Your review of the VAC Phi 200 was spot-on across the board. You are so right about it. It is startling and amazing. It is the best amplifier that I have had in the house. (Of course, it's the first $10,000 amplifier I've listened to here!) So my Music Reference and the VAC PA-100/100 will be up for sale. I also had a chance to listen to the Quicksilver V4s. Anyway, thanks for all of your input.
A quick question: I see that in your system list you are using the Cardas Golden Reference power cord. Is that a cord that you think is particularly good?
A friend was over yesterday and brought NOS 6550 tubes that sounded really nice in the Phi. I'd guess that Kevin would say that they wouldn't be a good choice, but have you tried any different tubes from stock in the Phi?
No, I haven't tried any output tubes other than stock with the Phi 200, but I have rolled NOS signal tubes into it -- extensively. Sylvania '52 Bad Boys, Tung-Sol roundplates, Brimar CV1988, Sylvania chrometops, etc., and found, in the end, that VAC's stock tubes do as fine a job as any in my system, to my ears. Not to say there wasn't any difference, but that the differences were more fine and tonal than major.
I've TS 6550 greyplates from the '70s I could try in the Phi 200, but, again, the amp sounds splendid stock and I've little motivation to roll output tubes into it.
Kevin uses Shuguang 6SN7s as input and driver tubes and, he tells me, he's started experimenting with the Psvane 6SN7s that are getting so much attention nowadays. I've tried Psvane EL84s, 12AX7s, and KT88s with very good success. I like them all and prefer them to NOS for being more affordable and replaceable!
As for the Cardas Golden Reference power cords -- yes, they are indeed very good, especially given the price point. But I'm now reviewing other power cords from another manufacturer -- established, European, and more expensive -- that I think are even better. Look for the review soon on Ultra Audio! . . . Garrett Hongo