When the speakers must be invisible, the answer is built-in speakers. Built-in speakers for the bathroom or kitchen have become incredibly popular as it provides an entirely discreet installation without necessarily compromising the sound quality. Combine a couple of good built-in speakers with, eg. The user-friendly Sonos Connect AMP will also give the possibility to stream music wirelessly to the speakers from a smartphone or tablet - in multiple rooms.
Speakers for installation in the ceiling most often used in the kitchen, bathroom or hallway/hallway. Here you do not necessarily expect the same sound quality as from the Hi-Fi system in the living room, because when the speakers are built into the ceiling, the stereo perspective disappears. That is, it is not a system you sit and listen closely to, it is background, coziness and maybe even party music that they will often be used for. Typically, in combination with a Sonos Connect AMP or other multi-room amplifier and streaming solution. Of course, ceiling speakers are also the only real solution for a Dolby Atmos configuration, but can also be used as surround speakers.
A good speaker for installation in the wall will in many aspects be able to replace a good rack/floor speaker. Since most built-in speakers are based on the same tweeters and bass/midrange devices as traditional speakers from the same brand. However, the large bottleneck is often in the representation of the bass, where one cannot expect to get the same amount of bass, as from a traditional speaker. This can be solved with a completely normal subwoofer or possibly, a built-in subwoofer. Wall mounting speakers can therefore easily be used as front speakers in a stereo solution or all around in a 5.1 surround setup.