Apple Airport allows you to stream wirelessly from iOS or Macs to a variety of wireless speakers and sound systems. I have various speakers in different parts of the house and this now changes the way I listen to music. Using Wi-Fi, you don't have to worry about range issues and the sound quality far exceeds bluetooth.
By default, iOS devices can only stream to one devices. When you play a song, you can pick which remote speaker to listen to. This by itself is cool but the cool part comes with multiple, simultaneous streams.
Desktop Macs and PC's running iTunes can stream to multiple speakers simultaneously all at the same time. If you have a dedicated iTunes server running, you can make up for iOS's single speaker deficiency by using the iOS devices as a remote control. As a remote, you can stream to multiple speakers in multiple rooms.
Here, I have the computer, the speakers in the basement, dining room, and master bedroom all playing at different volumes. This is simply brilliant!
This is why I love the Airplay protocol. I can walk from floor to floor, room to room, and all hear the same music in my 3 story house. I can initiate a stream in my Master bedroom and walk across multiple rooms and hear all the same track.
The first speaker I have is the Klipsch Gallery G17 Air. I use this in my bedroom because it covers a decent size area. I originally had this in the living room but decided I want speakers with more "stereo" soundstage separation in the living room. A majority of these portable speakers suffer one thing: lack of sound stage and most of them sound mono to me. When you are up close, they sound great but the farther you get, you realize you lose stereo separation. The Klipsch uses a bass reflex enclosure so the sound is very "punchy" for being a small set of speakers. Don't get me wrong, they do sound very good. These once retailed closed to $500 and have been compared to the Bowers and Wilkins Air Zeppelin. I would say these are one of the better small wireless speakers you can get on the market.
For the bedroom, they work fine. I also alternate between airplay mode and direct line mode to my iPod classic.
The next system is the Sony DLNA compatible SA-NS500 portable wireless speaker. This is a unique cylinder cone design. The top acts as a handle and it is great for lugging around because it has one trump card - batteries for 5-6 hours of portable sound. I normally leave it in the Dining room but I often take it outside to keep me company when I am washing and waxing the car on the weekend.
The shape is designed to punch sounds indifferent direction. It has 4 30mm two way speakers and a small 110mm sub woofer.
Again, the Sony is a good sound speaker but you won't get any soundstage. Early reviews were mixed on this but with later firmware revisions, Sony worked out most of the kinks. This also supports DLNA.
My next set-up is a not really a speaker system. Rather, a converted PogoPlug running ArchLinux and shairport. I had a spare PogoPlug and a few older 2.1 computer speakers. I figure I throw it in my basement and it works pretty great. Open source hackable solution. All you need is a USB sound card, some speakers, and ArchLinux running on these PogoPlug. I will probably build some more PogoPlug "Airplay" receivers that will expand my speaker lineup. You can read about it here.
I also have an AppleTV connected to my TV and sound system but I really don't use it for audio Airplay streaming chores.
Lastly, the living room. I thought long and hard on this. I shopped around and looked at a few options. I really didn't want to put a stereo system in the living room because I wanted it to be minimalist as much as possible. However, I spend a lot of time in there relaxing and lounging. I seriously considered the Bowers and Wilkins A5 and A7. Price wasn't really an issue as I spent quite a bit of money furnishing the living room already. The problem withe the Bowers and Wilkins' A7 is the same with the Klipsch, Sony and myriad of other "Airplay" enable speakers. They all lack soundstage and stereo imaging. Your left and right speakers should ideally be a few feet apart (say 6 feet) to have any stereophonic effect. Most of the music I listen to, 80s and 90s music, are heavily mixed with stereo effects. I also listen to a lot of live concert recordings.
The solution I came up was an Apple Airplay Express plus the well reviewed and acclaimed AudioEngine A5+ speakers. The AudioEngine is a good midrange $400 studio monitor quality speakers. This is a popular home-brew Airplay set-up and I now know why it is popular. They sound amazing.
For now,I don't have the DAC (Digital to Analog Converter) but I plan to add that in a few weeks. This is by far, one of the better solutions out there even without an added DAC. I wanted clear, accurate sound. For the price, the A5+ are amazing. They don't have that artificial bassy, hyped sound. Just go on Google and read up on the AudioEngines, they are amazing powered speakers for the price. This is what I ended up and I'm very satisfied.
So there you have it. This one geek's streaming audio home set-up.
AudioEngine A5+: http://audioengineusa.com/Store/Audioengine-A5plus
Klipsch G17: http://www.klipsch.com/gallery-g17-air/