Yep rumble filter needed....Had a phono amp, cheap variety no rumble filter, bought a little better one with rumble filter, woofers dead solid, dead silent. There is not much below 20hz on a vinyl pressing accept surface noise, so you won't lose anything in the musical sense, just background noise.
Now if you did not have this issue before this arm all together and another one you used originally did not exhibit "this issue" on "this same system" in question than yes it is coming more from the new cart/arm combo, however still can be eliminated using a phono stage with a rumble filter or adding the after market version stated above. Either way you need to block that noise, so starting over with a perfect cart/ arm combo may not be easy, and unnecessary until you try a rumble filter.
Good luck