After all of the postings, if you are still interested in a High-End tube preamp with tone controls, you should take a look at the AIR-TIGHT ATC-7. I talked to the Jack Miura (the current owner and son of the founder Atsushi Miura) at AXPONA about why he added "Tone Controls" to the ATC-7, and he said that they are still receiving a lot of requests for them. Here is a link to their product summary on the ATC-7 where they describe their Presence and Bass Control functions, and you can see the curves at the bottom for how much adjustment they provide. To keep the performance high, the ATC-7 does not use variable gain or attenuation, but each click of the control knobs changes the signal path through separate discrete components. It is an expensive piece at $34,800 for US list price, but if you want a top tier tube preamp with tone controls, this is one of the few best performance options that I know.
http://www.airtight-anm.com/_src/10816/ATC-7カタログ_E_1205.pdf?v=1686128074592