The square head ones make more noise, but everything I've used that was old was from about 1930 to to probably no later than 1950, had the round gibbed head with standard (but now rapidly being replaced) straight knives. Most had direct drive. Sometimes I wonder just how many videos are on line with jointers running with coins on edge! When I first started working, the company actually still had one "line drive" but It wasn't long before they took it out. I mention that because I'm guessing they made a point of prioritizing removing square heads.