I am saying this specifically for TVC. I have said this many times and will repeat again. You need to make sure that a TVC should have a MATCHING system. You really need to look into the source voltage, amplifier sensitivity, loudspeaker sensitivity, cables, etc for your system to "come alive" with the TVC. If you have taken good care, then it is really difficult to beat a well made TVC. Years back I heard that the "core" of the TVC also made a difference. From my personal experience I have compared my $1.6K TVC to a $4K active preamp and the preamp went back to the dealer. I have plenty gain in my system and absolutely have no issues with bass or treble. At this point, my speakers go down to only 40Hz. I am looking forward to upgrade to a loudspeaker that goes down to at least 30Hz. I am sure that my TVC can easily handle that.
I used to think passive preamps were superior to active preamps given right the setup, but
my recent evaluation of a modded old SS preamp has me a little befuddled. I've evaluated $10K+ active preamps in the past and was never impressed especially given their cost. In general, I've found passives to do better job. I know there's ongoing debate on this. But here's a very illuminating video on the subject by Bascom King, one of the legends of high end audio.
https://youtu.be/HHl8F9amyY4
https://youtu.be/HHl8F9amyY4