We had this issue with our male cat, as well.
We initially went with prescription dry food (Science Diet C/D), but that wasn’t doing the trick, and we switched to canned (wet) C/D. It definitely seemed like part of the issue was that the cat wasn’t drinking enough water, and the canned seemed to help this (no recurrence of the crystals since we switched to canned).
However, last year, my wife started doing some reading about the Science Diet foods, and wasn’t happy with what she learned (the “Seafood” version, for example, lists pork bits as its first two ingredients). As it’s also an expensive food, she did a bunch of research on what other options are out there.
We tried a number of canned foods that we found at PetSmart, primarily looking for low ash content, high protein, and low-ish fat content. Some he liked, some he turned up his nose at. We settled on one of Blue’s foods, Freedom, as the one he likes the best, but we rotate in a couple of other Blue Wilderness varieties as treats for him (they have higher fat levels, so we don’t give those to him every day). We also put in a little bit of water (mashing it up with the food) every day, just to try to get him a little more water.