If you got your bow directly from Prochownik he used Canadian white hair, which is not common in the bow market. He lived in Winnipeg for quite a while and might have had a local source for hair, as I can't think of any of the big hair suppliers that are selling Canadian hair as an option. From my experience with my own, two from a colleague that inspired me to order one, and a half a dozen or so others that were in my bass playing circle at the time, it is great hair, but very slightly coarser than the white that you will see from shops/rehairers offering white hair.
If it has been rehaired by anyone else or if Prochownik has changed hair suppliers, then it could have been a more typical/common white. A lot of people have a slightly coarser grade of white for bass or will blend a bit of it in with what they use for violin, viola, cello, etc. with the assumption that there is such a thing as "too fine" on a bass bow. Some people put the same hair in everything and white means the white they use in violin bows too, so it's worth asking what your rehairer does.
If you have access to the hair before it goes in a bow/has rosin on it, there are very fine whites out there where the hair is very thin, smooth, delicate, and has a lot of stretch in it. Many players equate that to the sound they get out of it too, where they find it to be a smoother, more delicate, more flexible, and lighter sound. This tends to be the recommendation for people who are doing a lot of solo, chamber music, small ensemble work, and sometimes recordings, for a "pure" sound.
Black hair on the other end of the spectrum tends to be much coarser, thicker, rougher, not as delicate, and doesn't have as much stretch to it. This tends to be more grab, holds rosin better or holds more of it, and it can be more of a brute/blunt force weapon, that comes with a bit more grit, sizzle, or roughness in the sound. While the end of that list might sound like negative characteristics, they tend to disappear farther into a bigger hall, or beneath the sound of a larger ensemble, and are usually considered worth the cost to someone who likes the benefits they get out of black.
Chestnut is somewhere in the middle, leaning 60-75% more towards the black end of the spectrum. It is coarser than white, but not as extreme as black can be. A salt and pepper blend of white and black can be compared to chestnut in many ways, although that also depends on what the percentage of the blend is. It can be a "best of both worlds" where you still feel the positives of black without the trade offs, without completely loosing the niceties of white. It can also be a "master of none" where you feel like you've lost the benefits of both ends of the spectrum. When I was offering it as an option, it was something that players either loved or hated, I didn't see a lot of middle ground opinions on it.
All of which can be emphasized by rosin choice too, with harder rosins tending towards the white hair characteristics, and softer tending towards the black.
I always found my Prochownik wants to play light, delicate, solo-ish, higher up the instrument, and gives a really clear sound that's pretty pure and focused, and white draws out all of those characteristics from me and that bow. Silver, chestnut, salt and pepper, and then black in that order seemed to be trying to turn it into something it was not. I have another bow that wants to play in the bass part of the bass and punch out orchestra stuff that seems to like black more than white, and instead of trying to compensate for what they are to some sort of middle ground, I've been happier leaning into their characteristics and switching between the two when I switch what I am playing.
If you like what's in there and how it has played with chestnut, don't fix what ain't broken. If you are looking for a little "prettier" sound than what you are getting, then maybe white. Either way, a good rehair is going to be a step in the right direction.
