For the most part, subs and turntables didn't exist at the same time.
When TT were popular, subs hadn't entered the picture yet for most people. Yet, electronics manufacturers were still offering those infrasonic filters for people who had problems with rumble due to speaker/TT positioning or speaker systems that offered pretty low bass. Now, those switches don't seem to exist anymore, even though TT have made a bit of a comeback and people are using them in systems with subs.
I don't think you'll be missing out on any actual music info if you simply switch off the sub when listening to the TT. I don't remember what speakers you have (M22s or M3s maybe?), but certainly if they are floorstanders, you could run those full-range and get all the bass you'll extract with your TT!
