Thanks for tips! I've been rolling some 12AT7's in and tried a Valve Art 274b.
The 5U4 that was in it is a better mix to my ears. The VA was very neutral, but
a bit light in the bass/midbass. Been thinking about trying some El84's, but
wondering how much I'd miss the "hazengrid" if I took out the Russian tubes.
I find that I'm hearing some layering and staging cues that I haven't heard before.
I like the Taboo a lot and find it a very nice companion to my Koss electrostatics.