12ax7 question

Has anyone ever seen or heard of a clear top 12ax7? a friend of mine stoped by and dropped a pair in my had and said try these baby's out! i listend to the tubes i had in my pas3x for about an hour an record. sovtek's then swaped them out of the phono section and I couldn't believe the differance! Music Sweet Music!
Goose Bumps and a cold chill threw out my whole Body. Does any one know anything about them?

P.S. I got another pair on the way! well gotta go and play

I've got a couple of sets of those, in both 12ax7 and 12au7s. Those are RCA Cleartops (suprisingly enough.) Lots of info on the web, try the Tubes Asylum over at Audio Asylum. They sound a little bright and harsh in my system but very extended on the top end. Overall, good tube for the money, just not MY favorite. Some, as you, just love them. Brent Jesse, Jim Mcshane and others carry them regularly. Not particularly hard to find.
Dave

http://db.audioasylum.com/cgi/search.mpl?forum=tubes&searchtext=cleartop

these are very well known as good sounding tubes, I've got about 4 pairs of them

Thanks for the replys! I did find some info on the web. I think I was really impressed because the tubes i was using were sovtek!
Thanks again!

Certainly a big step up from there in all liklehood.