At 1900 your general chess understanding should be big enough to just get a heavyweight. I recommend  Dvoretsky's Endgame Manual. I was very surprised how focused on practical matters his book is. He reduces the theoretical stuff to the absolute minimum and sorts the material by importance (via font size in the German version).
The direct competition is Fundamental Chess Endings by Müller & Lamprecht. It's common understanding that both book are on the same level. The choice is a matter of taste.

If you want something simpler buy 100 Endgames You Must Know by de la Villa. Delivers exactly what the name says, often with 2 example per endgame. This book covers all the important stuff. The author is very good at pressing the sample positions into rules you can memorize. He leaves out everything which he believes has no practical value. 

Both books are very good and quite different. Even getting both could be an idea.

I am personally very fond of Flear's endgame books (improve and mastering the endgame). It goes the entire width, but also into the deep at occasion