@wig , thanks, this is very helpful. I will probably pick up a 274B to try in my PS 9.0. So far, the Canadian Westinghouse V-71 is the best rectifier I've come across by a substantial margin, including the GZ34 Mullard and the Philips tube that Dan Wright prefers. Brent Jesse put me on to the Westinghouse, but as far as I can tell, these are now unavailable. I've had two of these tubes go bad in the last 12 years or so, and I still have 2 spares, but I'd love to find a current production alternative.
I need 8 6SN7s in my AtmaSphere amps. I won't be spending $1600 to retube my M-60s. Also, there is not space for more than 2 of the Sophias per channel. I may pick up one pair to rotate through the 4 positions just to see what gives. You've given me some good advise in the past so I trust your ears. But those 6SN7s are mighty pricey.
I need 8 6SN7s in my AtmaSphere amps. I won't be spending $1600 to retube my M-60s. Also, there is not space for more than 2 of the Sophias per channel. I may pick up one pair to rotate through the 4 positions just to see what gives. You've given me some good advise in the past so I trust your ears. But those 6SN7s are mighty pricey.