I decided to try ti flats on a fender P because I love Pino’s tone and flatwounds in general.
They feel amazing to play. The output on them is crazy, it feels like I barely have to touch the strings to get a full sound.
But the midrange is INTENSE and very honky. I can eq a lot of it out by boosting bass but is it normal for them to be like this new?
Will some bottom end come in as they settle in? What kind of time frame are we talking about?
IME, the answers to your questions are; yes; yeah, a little; and it depends on how long you play them at a sitting.
TIJF's, like most flats, have kind of a dud E string at first, along with very bright A, D, and G strings. As they break in, the E string will get brighter, and the other strings will lose some of the brightness. When they all meet in the middle somewhere? They're broken in. However... TIJF's are
not known for their low end tone. They are known for their low-mids, mids, and high end - along with their superb harmonic overtones. IME, their bottom end is... adequate, at best. Some basses can accentuate that bottom end a bit - and some can not. The bass I have that wears TI's - an Alembic Epic - certainly can, but I also have basses that can not...
How long they will take to break in, mostly depends on you. TI's are sorta notorious for taking a good long while to break in. The ones on my Alembic took about a year, but I wasn't in a much of a hurry. I had... well, a lot... of other basses with strings that needed breaking in, and I was never going to play the Alembic a lot, anyway. I only use it for Jazz, and I don't play that a whole lot, so...
In any case; the more you play them, the quicker they'll break in. But, you'll have to play them a lot...