Since you mentioned building your own… this article should be required reading for anyone with a soldering iron.
You wanna build stuff correctly, and aoid problems down the road? Read this over and over until it makes sense.
https://www.rane.com/note110.html
Now that you have read it.. you are likely facing an unbalanced to balanced interface, if your mixer is of reasonable quality. You will probably get away with stadard TS cables.. but there are better ways if you run into noise. Hopefully you just read two of them 🙂