And here is another review of them:
http://www.tonepublications.com/gear/tj-music-full-music-vacuum-tubes/Statements that I really agree with are: "Dynamics were increased, with extension at both ends of the frequency scale, without any harshness"
"....the horns jumped out of the speaker plane and were right in front of me, with the image having much more front to back dimensionality."
I have used the following 12AX7's in my ARC Pre: JJ (ARC Supplied), Mullard (New Release), Matsushita (NOS), Sylvania (NOS), and the TJ.
In my setup I found the TJ and Sylvania to be very close with the TJ having better defined frequency extensions. Both presented a wide and deep sound stage.
The Mats are also nice sounding, but with less top end and a sound stage not quite as vast as the TJ and Sylvania.
The Mullard and JJ sound more on the same plane as the speakers - almost flat sounding compared to the TJ and Sylvania.
For "New" tubes, instead of having to search endlessly for NOS, they are a great tube to consider in a rig. But like any other tube, it is really system and synergy dependent on the each persons results.
GF offers for an additional $10, a 12 Month warranty on the tubes. While there has been no reports of early failures with the TJ, $10 is worth it in my opinion for more peace of mind.
