Takatsuki 300B 2 different models, anyone noticed?

The rounded version may provide a smaller (more concentrated) area of contact, but a stronger/better one.

It also seems that it would be easier to insert VS the rectangular version.

If the construction/materials remain the same I doubt that it would make an audible difference in an SET design as I could never hear a difference between unmatched 300B’s (same tubes/different test readings) in an Audion amp and the same with 2A3’s in my Bottlehead amps.

Just guesses.

DeKay

Do they change the sound if they make them in another shape as you can see on the pictures?

There must be a reason why they changed them....

I also saw they have manufactured a new production in the spring this year.

Thank's for helping me...Jond and Jason!

@jasonbourne52 , the “glasses” are typically made from mica and are used to support and align the tube internals inside the glass envelope. In some instance, they may be attached to the getter.  

Those "glasses" are called "getters". They are used to remove residual gases left inside tubes after vacuum pumping.

It's fine to both post links and pics for pics just copy paste from the web.

I mean the ones with the black base and yellow and red letters.

I think it is not allowed to put links on this forum?

Just seach google on pictures.

Can you show the internet link ?

I am a robot