Tube question

[ADAddicted]

Hey guys... these are the tubes in my Ver:2.1 MP-1... I was wondering if they are the original tubes or not. Thanks for any input. Mike

[Rusty]

From what I can remember, in my first MP-1 back in the late 80's the original tubes that where in there had no markings or paint on them at all and they lasted very well compared to any other ones that I have put in there since.

Someone else here will be able to give you more info on the National brand which I believe had a couple of factories worldwide and produced tubes for other companies, I do believe they were good quality valves.

Is there any other markings on those tubes, there may be a date/factory code on them?

[MarshallJMP]

ADA did use National branded tubes, but to say if these are the originals ,can't tell. The early ones had the National brand on them but these weren't Chinese tubes. Later on they just had 12AX7a on then in red inkt but no brand name, and these where Chinese. These Nationals you have are also Chinese tubes.

[ADAddicted]

Right on... thanks for the replies. It really doesn't matter. Was just curious if ADA used a particular tube brand or not. Thanks guys.