No, and not much interested. Thing is, of all the tubes I've tried, its not that there aren't difference but rather what differences there are simply are not enough for me to care. And I am a guy who cares about really small things. The only one I recall being worth it was 6550 to KT88, where I prefer KT88. But even then its pretty small.
In contrast to that is the difference between two very similar amps running the same tubes. In those cases I have to think its almost all down to the transformers. I've swapped caps, resistors, diodes, wire, pretty much everything but transformers. And circuit topography, I'm nowhere near being able to evaluate that. But from what I do know it sure seems transformers are the real key to glorious tube amp sound.
The main problem I think is no one can roll transformers. I even keep my old Aronov amp around mostly because I keep thinking its transformers are largely to credit for its superb range and depth and I might one day have time to learn enough about electronics to restore and rebuild it.
In contrast to that is the difference between two very similar amps running the same tubes. In those cases I have to think its almost all down to the transformers. I've swapped caps, resistors, diodes, wire, pretty much everything but transformers. And circuit topography, I'm nowhere near being able to evaluate that. But from what I do know it sure seems transformers are the real key to glorious tube amp sound.
The main problem I think is no one can roll transformers. I even keep my old Aronov amp around mostly because I keep thinking its transformers are largely to credit for its superb range and depth and I might one day have time to learn enough about electronics to restore and rebuild it.