Two Toned Plate?

[Andyman]

Anybody ever see this before? I haven’t.

The plate in this Sylvania 6V6GT is black on the bottom and silver/grey on the top. Whatever process they used to blacken the plate missed the top.

My question is, will it make any sonic difference in the real world? Let me know,

 

[Buck Rogers]

The metal in "Black Plate" tubes is a highly refined steel that is more expensive than gray plate steel.

As far as I know the only color changing treatment they get is an Annealing process to help the steel out-gas and purify it before assembly.

I like 6V6's with the Round or Oval plates they sound best for HiFi amps.

I doubt you will hearing anything different if the tube tests good.

 

[gadget73]

sure is unusual looking, can't say I've run into that before.

 

[Andyman]

Me neither and I’ve looked at thousands of tubes.

 

[Mr Boochie]

Anybody ever see this before? I haven’t.

The plate in this Sylvania 6V6GT is black on the bottom and silver/grey on the top. Whatever process they used to blacken the plate missed the top.

My question is, will it make any sonic difference in the real world? Let me know,View attachment 3860392View attachment 3860393

Ultimately, if it's a strong and quiet tube, don't worry about it. It slipped through QA and has survived all these years.

A little blurb on what makes black plates black.