There was straight line (not frequency selective) and frequency selective that would ring at only certain ring frequencies.
As I understand the history, it was almost exclusively the independents which used frequency selective ringing (it makes sense, therefore, that Automatic Electric had these tuned ringers).
Ma Bell had a 4-way party line arrangement with fully selective ringing. Two parties had their ringers connected tip-to-ground, two were ring-to-ground, and they all had a cold-cathode tube in series. By applying a suitable positive or negative bias the equipment could selectively ring each of the four phones individually.
Then by using a combination of single and double rings the same basic arrangement could make an 8-way party line, no longer with fully selective ringing but each phone would only ring for its own calls and those of one other party.
Some small SxS offices had a 10-way party line system with coded ringing in which the last digit of the number determined the ring cadence and whether ringing voltage was applied to ring or tip. For example, 4931=long, 4932=short-short, 4933=long-short, and so on, then 4936 through 4930 repeated the same codes on the other side of the line. People on a single-line would always have a number ending in 1.