Rolling KT150s in Primaluna hp integrated

Jb I feel the KT 150 tube is about as ideal an output in a pp design for my purposes. I recently installed a matched quad of cryoed 150s in my quicksilver silver 88s for further refinement, such subtle nuances were further revealed. Don’t really know what is going on but I can’t imagine things getting much better. I hear no downside but then again tubeoholics have different goals and values in what their focus is. It is definitely not a "tubey" or unduly colored tube for those inclined toward that end. It just sounds more like real music to me.

If you do go back to the 150s Wolf, try the cryoed, not too much more, less than 400.00 for a matched quad. Got them off a vendor on eBay. They biased very close, very nice tubes. I also have a matched quad of Russian Genelex Gold Lions I originally purchased for my MC-60 amps, few hours. Also tried in the Silver 88s. The uncryoed 150s had more everything, at least in those amps. The cryoed  150s caught me completely by surprise. I offered to lend to a friend to hear in his amps but changed my mind after I put them in mine first. He's getting the other ones.   

George maybe you're right but then again maybe if the tube goes through the cryogenic process one may well end up with a better tube for having survived. This would be providing nothing before and after changes with regard to measurements and vacuum leakage. All I can say with any certainty is not so much about whether it works or not only that the cryoed tubes sounded better, CLEARLY. I have read some of the debate and controversy concerning this issue, seems more nay than yeah at least with regard to tubes. In my case it very well may be that there was more miles on my original KT150s than I realized and that putting in fresh tubes made the difference and it had nothing to do with the cryogenic process. I have to find out the parameters to test all the subjects (KT150s) on my Hickcock to see if this might be the reason or at least give me a clue. 

"The sound is to die for", different amp(s), same result, Jbhiller, I agree. The KT-150 tube is the difference. Temperature effect would depend on many factors, room size, amps, local, season, etc not withstanding George's technical considerations. 
 

Great idea George! I didn't think of that. Comparing test results through a Hickcock tube tester probably won't tell me all I need to know with regard to the effects of cryoing the original tubes and comparing directly.