Carpathian, even though I took a bit of abuse from one member for having mentioned my preamp more than once, since you asked, it is the Herron VTSP-3A tube preamplifier, it is one of the early ones that were first developed by Keith Herron, it uses six 6922 tubes, where later units only have four 6922s.
I don't know if this makes much of a difference in sound quality, but I love this preamp far beyond any other I have ever owned or heard. I'm not much of a well-traveled audiophile, but I am astonished at the spectacular improvement in how my system sounds. You can see what my system is composed of in Virtual Systems- Done For Now, under the name of "The Summit", meaning my personal summit.
Custom built HPD Tannoy speakers, DIY custom crossovers, and 3C24 tube power amp designed and built by Paul Birkeland are the main contributors in the stereo part of my music-home theater system.
Thank you for asking, regards,
Dan Thomason