04-04-15: Quincy
Very good comments and feed back. Thank you. NOS is just that; NOS. No one 'really' knows where they have been or how and if they have been used. No one knows how many times they were bought and sold through middlemen and liquidators. I agree that any new tube can sit on a shelf for 100 years with no issue, but apply the voltage and the clock is ticking. NOS has been out of production for so long (~50 years) one would hope that those still making tubes have developed some manufacturing advancements to insure better quality control. Once again... Thanks!
That's precisely why I only purchase NOS from reputable dealers.
In order for advancement, you need demand that triggers investment. I think demand for tubes are probably higher ~50 years ago so I doubt any recent break through.
Also some raw materials use to make NOS are ban so new tube quality suffers in terms of SQ and durability.
I've been rolling tubes forever and haven't found many or any new small signal tubes beat a NOS. Now power tubes are a different story.
