Amazon brought multiroom audio support to its Echo speakers a few months ago, but let's face it: unless you're a big fan of Amazon Music Unlimited, it hasn't been very useful for on-demand streaming. That changes today. As promised, Amazon has added multiroom support for Spotify (oh, and SiriusXM) to let you play the tunes of your choice across more than one Echo at a time, including groups. You won't have to stop listening to an album just because you've moved from the living room to the kitchen.