They do say Tad Laboratories on the back of them.
Amps confuse me. Once they measure well it’s more of a different flavor and preference. For example I just sold a Micromega M100. Nice sounding amp but I far prefer the A1008 which was a 6 grand integrated in its day. Not sure how far up the ladder I would need to go to get an appreciable improvement. The Pass Labs stuff does intrigue me as well as the Ayre stuff. I just always buy based on reviews basically. I have no intention of buying new so feel like a creep using dealers to listen to their setups when they are trying to make a living.