GG, thanks for sharing.
With such effort, you really deserve to get great pictures. Bravo.
Ian, thanks for the clarification on the heat too.
I really lost counts when did the tubes hunting.
Even up to now, I believe I might missed something on the list.
But frankly speaking, I was a bit surprised to realize that I've ordered that much.
Ian, thanks again for such brief and precise description.
It's really exciting to understand these tubes characteristics and their historical tributes.
your tube list by far exceeds any exspectation one could have had. i strongly propose to buy a second amp for tube burn in!!!!!!!
i don't know where you are living but at least within europe it would be no problem (no customs) to send my grado to one of you for an expert review as i would be more than interested in another opinion about how they sound and suggestions how to further improve my headphone designs.
here is a link to a not complete list of tube manufacturers: