They sound quite good, but want to spend more time with them - fairly confident they will enter my rotation - they definitely have an some very unique sonic characteristics to them.. very fast/detailed and what some might refer to as "sparkly" top end, but also some really punchy and dynamic low end in the bass and sub bass.. I don't know that I have heard any other 6SN7 sound quite like this - will have to do some comparisons.I have these same tubes. The only difference I see if my tubes have Rogers printed in green.
I bought them pre pandemic from a guy in Vancouver. I want to say they were very fairly priced. It was a bigger buy for me because I remember he sold them as a lot of 7-8 6SN7s. I don't remember having listened to them at all. I'll have to look for them and give them a listen soon. How do you like them?
The interesting thing with some of the Canadian made tubes, is that there was some made in the 70's that say they were made in Canada that I think were actually made in Japan. As far as I know by the early 1970's most of the few Canadian tube factories were shutting down. I think Japan was taking over most of the tube production.
From the base of the tubes showing "37-54", I believe these were made 37th week of 1954 .. least that is my first thought.