I do have limited experience with tubes (I’m a solid state guy). Though, I do have some comments:
I do like the PSVANE tubes very much. I would say that they are just about the highest resolution and least colored tubes that you can get. I don’t know how this will turn out in your particular system or how it will compare to your Seimens. I will say that the PSVANE are very clean and clear. If you are getting a harshness/brightness in the upper mids/highs, I would say that there is something else in your system that is contributing to this (such as silver wire, metal dome tweeters, metal cone midranges, etc.). The PSVANE could definitely reveal flaws in other sections of your system.
That being said, I will say that the true old Amperex Holland 12ax7 tubes are just excellent. They do not have the resolution and clarity or speed of attack as the PSVANE, but there is just "magic" about them that makes the music so emotionally engaging and so "live" and "naturally analog" in a sense. However, it is extremely difficult to get the "real" Amperex tubes without being screwed over with fake tubes and fake sellers. They can be very expensive (like $400-500 for a pair of 12ax7).
I do like the PSVANE tubes very much. I would say that they are just about the highest resolution and least colored tubes that you can get. I don’t know how this will turn out in your particular system or how it will compare to your Seimens. I will say that the PSVANE are very clean and clear. If you are getting a harshness/brightness in the upper mids/highs, I would say that there is something else in your system that is contributing to this (such as silver wire, metal dome tweeters, metal cone midranges, etc.). The PSVANE could definitely reveal flaws in other sections of your system.
That being said, I will say that the true old Amperex Holland 12ax7 tubes are just excellent. They do not have the resolution and clarity or speed of attack as the PSVANE, but there is just "magic" about them that makes the music so emotionally engaging and so "live" and "naturally analog" in a sense. However, it is extremely difficult to get the "real" Amperex tubes without being screwed over with fake tubes and fake sellers. They can be very expensive (like $400-500 for a pair of 12ax7).