[rgs9200m]

Tone Audio mentions them here:
http://www.tonepublications.com/review/tj-music-full-music-vacuum-tubes/
 
So does 6moons in an Eddie Current review:
http://www.6moons.com/audioreviews/eddiecurrent3/2.html
 
As far as I can see, you have to buy them from "Sun Wu's" store on Alibaba/Aliexpress in China and have them mailed to the U.S.
For instance:
http://www.aliexpress.com/item/Matched-Pair-PX4-n-Vacuum-Tube-for-stereo-amplifier/823893317.html
 
Thanks.

 

[Stereolab42]

They are Sophia Electric rejects... Beware.

 

[rgs9200m]

OK, thanks.

 

[fhuang]

yea, i have a pair of 300b.  my first upgrade from stock tubes.  decent tubes and works fine.  that's not the answer you're looking for right?  looking for something different for your b52?

 

[rgs9200m]

Thank Fhuang. Actually, I spent some time reading about the TJ Full Music tubes on the web (audiogon and other places) and they do seem to have quite a following and history, and there are many posts about them, with many good reports and some detractors.
It's for PX4 tubes. So I may give them a try. (It seems all new production PX4 tubes come from their factory, actually.)

 

[MattKaye]

Years later but for anyone seeing the thread now, Full Music tubes are better than the gold lions, which seem to be the standard here in the US for whatever reason, probably cuz upscale pushes them so much. Sophia Electric blue glass tubes are better than the Full Musics though.