A Telefunken smooth plate 12AX7 might hit a good balance between the Amperex (Philips) and Siemens.
I dont like any Mullard 12AX7. I also dont care for any U.S. made 12AX7 except perhaps for the old stock Tung-Sols.
If you can live with roughly 30% less gain, 5751s are great tubes. Best of these are: Raytheon Windmill Getter (double mica), GE and Sylvania triple mica black plates. For less money, the double mica Tung-Sol is also good.
I dont like any Mullard 12AX7. I also dont care for any U.S. made 12AX7 except perhaps for the old stock Tung-Sols.
If you can live with roughly 30% less gain, 5751s are great tubes. Best of these are: Raytheon Windmill Getter (double mica), GE and Sylvania triple mica black plates. For less money, the double mica Tung-Sol is also good.