Yeah, that was a surprise to me. That little amp actually sits nice in a mix.
The stock tubes were HORRIBLE so I pulled those and replaced them right away. Since it only has a single 12AX7 & EL84 tube quality matters so I broke out my stash and auditioned a few vintage tubes. I had an old Westinghouse labeled 6BQ5 that tested well so I threw that in then ran through a bunch of vintage 12AX7's. At first I planned to just try a few I63 Mullards and an Amperex thinking one of those would be great. I was pretty floored buy the amopunt of difference I could hear between each tube so I dug in the stash for more and tried all kinds of vintage tubes as a well as a few modern tubes. The amount of gain stages really makes the preamp tube sensitive. I was fun. The one that sounded the best in the T5 was a Baldwin labeled Sylvania long plate. I had a few because I bought them for years for use in the PI slot of my amps. They consistently test super strong which is great in that position. I could even hear the difference between each of those which I've never experienced before.