Help identifying these EL34s??

[teleking36]

I recently received my two Marantz Model 9 monoblock power amps back from my tech, and he installed all new Svetlana Winged C EL34s in the amps. He pulled out these Philiips 6CA7s, five of which had lost their vacuum. These three tubes appear to be ok, but I didn't get them tested. They have double O getters; i can't seem to locate any manufacturing code on them.

Could anyone tell me specifically where these came from and when they were made? Thanks!

http://i118.photobucket.com/albums/o99/teleking36/DSCN2176.jpg

http://i118.photobucket.com/albums/o99/teleking36/DSCN2177.jpg

http://i118.photobucket.com/albums/o99/teleking36/DSCN2179.jpg

[RussB]

Sylvania "Big Bottle" 6CA7's. Made in the USA

They look well used from the brownish coloring of the getter flash

[Swarty]

Sylvania "Big Bottle" 6CA7's. Made in the USA

They look well used from the brownish coloring of the getter flash

But still probably capable of more power/clarity than any current production EL34/6CA7.