Popcorn Ceiling vs Smooth

If you paint it, you throw the acoustic properties out the window. I can't count how many calls I've gotten to remove one way or another, popcorn ceilings that have been painted. They're horrible.

If you've got a fan hanging from the ceiling prepare yourself for when, after a few years, there'll be a ring of dust on the ceiling trapped in the popcorn. No matter if you try to vacuum or dust it the ceiling will shed everywhere! Nasty! I'm looking at my dust rings as I type!;)

If you home was built in the 50/60's the popcorn was to (or should be) removed, as it may contain asbestos.

I removed the popcorn from the ceiling in my kitchen; there is definetly more echo now.

I have a dropped down, acoustic, deep fissured ceiling, in my listening room. Adds to the great sound that I can get from the room. The floor is carpeted, so the room in itself is really quite 'dead', which was desired. Unlike popcorn ceilings, mine is deep fissured so it traps much more of the sound. So my recommendation is dump the popcorn, install a dropped ceiling like mine. You will be happy. With a dropped down ceiling, mine is 2x2 grid, there are endless acoustic 'drop ins', that can be added to further control the resonance you get from the ceiling.