Carlos269, one of the things that all tube equipment manufacturers face nowadays is that tube quality is nowhere near what it was 30-50 years ago! The EH tubes in the Einstein are a good example- nicely packaged but the tubes are microphonic, noisy if not hand-picked and prone to grid contamination in short order.
In the old days the tube manufacturers made plenty of spares; often they offer significantly better performance for not a lot of extra money. The problems one faces with this are several- the really top performers have a cult price, often the tubes are used when advertised as NOS, and certainly finding significant quantities of any type is tricky at best, which is why OEMs use the current manufactured tubes.
It is also true that NOS tubes may not perform as well- as in the case of 12AT7s, there are no NOS types as quiet as the new Chinese any longer as the quiet ones have been used up. Even so, NOS 12AT7s do sound smoother and more robust.
That said, I agree that setup and the technology itself plays a huge role. I think it is true to say that you and Fcrowder are both correct.
In the old days the tube manufacturers made plenty of spares; often they offer significantly better performance for not a lot of extra money. The problems one faces with this are several- the really top performers have a cult price, often the tubes are used when advertised as NOS, and certainly finding significant quantities of any type is tricky at best, which is why OEMs use the current manufactured tubes.
It is also true that NOS tubes may not perform as well- as in the case of 12AT7s, there are no NOS types as quiet as the new Chinese any longer as the quiet ones have been used up. Even so, NOS 12AT7s do sound smoother and more robust.
That said, I agree that setup and the technology itself plays a huge role. I think it is true to say that you and Fcrowder are both correct.