Feedback from owner who has owned both Treasure and Psvane 6CA7 (EL34) tubes: (original post on Audiokarma.org, member Pen Name)
“Ordered on Tuesday, a quad of these tubes were playing in my Shuguang I-25 on Thursday evening. Thanks for the great service, Rachel!
The Psvanes (not sure if this is an official brand-name typo or a copyright thing – but I think the name really ought to be Pavane) replaced Shuguang black treasure tubes that appeared to be getting a bit worn. When I ordered the tubes I was not certain that the rather modestly priced hardware of the I-25 would justify $360 of grade A glass – but now I am. The Psvanes are significantly better than the Shuguang treasure tubes, even without burn in and now with about 25 hours on them. Of course my memory of how good the treasure tubes were at their best has faded – but I do not remember the treasure tubes to be as incisive as the Psvanes. The Psvanes bring the system to a new level.
The I-25 really is a good little amp, capable of revealing the difference in these power tubes.”