Hi,
Just passing along this handy tutorial by Conor at libremusicproduction.com. Now you can have MIDI drums (and any other SF2 sounds of course) in Ardour versions newer than 5.4 without requiring any 3rd party plugins! Thanks to Conor for taking the time to write this tutorial, and the Ardour devs for this great new feature.
http://libremusicproduction.com/tutorials/using-avl-drumkits-fluid-synth-ardour