I just put in one of the new grove tube gt-12ax7m tubes into a n ear 834p phono preamp with a volume control into a e.a.r. 890 and am getting very good results. The sound is tight and controlled with good tonal qualities. The higher frequencies are more accurate than the tubes it came with. It also has the smoothness of NOS tubes I bought off of e-bay. Has anyone else tried these tubes out. They are just now available, so the older tubes may be different.