The Uillean pipes do indeed have drones, 3 like the Piob Mhor. Irish pipes are a parlour instrument. The differ from the highland pipes in a number of ways
  • Uillean pipes are bellows blown
  • Uillean pipes are quieter
  • Uillean pipes have keys whereas a Piob Mhor(great pipe) chanter is open holed
  • Uillean pipes are more complicated and take longer to learn to play... it is said 7 years learning and 7 more years to master...
  • Uillean pipes have 3 regulators, which are like primitive oboes

I would not go as far as to say that the Uillean pipes are a mournful instrument. The Scottish bagpipe is an instrument of war, merrymaking, and mourning... a lot of piobaireachd is slow lamentatious music. It is my experience that most Uillean pipe tunes are rather cheery... one need only listen to a few Chieftains tunes to see for oneself.