HomePod has multi-room support thanks to AirPlay 2, but your five-year-old Bluetooth speaker can't join in on the party. That is unless you have Airfoil. It's a simple program that lets you stream audio from your Mac or PC to any AirPlay and Bluetooth speakers at the sae tine.
Though you can currently AirPlay to multiple devices from iTunes on your Mac, it's only possible with iTunes and doesn't combine AirPlay and Bluetooth speakers. Airfoil is incredibly universal, allowing you to use AirPlay and Bluetooth to stream music to as many devices as you want from any audio source you want on your Mac or PC.
Did you say it works with both AirPlay and Bluetooth?
Yes! You can send audio to a multitude of AirPlay speakers, not just the HomePod. Do you already have half a dozen Bluetooth speakers? Not a problem. You can connect all of them to Airfoil and play audio from your Mac or PC across all of them at the same time.
That's right. Not only does Airfoil work with AirPlay speakers, it also works with Bluetooth. So, you can connect two HomePods in the living room, your Soundlink in the kitchen, and a UE Boom in your bathroom and walk throughout your entire house, playing whatever you want from your Mac.
Did you say PC?
That's right. You can use HomePod with any PC running Windows 7, Windows 8, or Windows 10.
Did you say any audio? Can I listen to Spotify? YouTube Music? Deezer?
You sure can. With Airfoil installed on your Mac or PC, you can select any application you want to send audio to pretty much all of your connected speakers. GarageBand? djay Pro? Plex? Yes. Yes. Yes.
Video games, movies, audiobooks, FaceTime, your home movies, all of it. You can even set up Airfoil to play the system audio from your Mac so it'll send the clicks, bleeps, and blips to your HomePod (if you're into that sort of thing).
What about syncing issues?
There is always going to be a little bit of audio lag when you first set up your multi-room speaker array. But, Airfoil has its own advanced speaker options that let us manually sync audio across all of the speakers playing audio.
When you drag the slider bar to the left or right for each speaker, it will adjust to sync up with the playback of the audio of another speaker.
I've done this with four different audio sources at once. It takes a little time to set it all up, but once everything is synced up, your whole house plays back the music. It's like living in a dance club or a movie theater.
But what about my iPhone?
Oh, did I forget to mention that with the companion Airfoil Satellite apps you can actually send audio from your iPhone, iPad, Apple TV, or another Mac or PC to your Mac and thusly through those multiple speakers you have connected? Yeah. You can do that.
When you play audio on your iPhone you'll just use the AirPlay button you normally do to send audio to an external speaker source. Tap your Mac as the receiver. Then, with Airfoil Satellite and Airfoil on your Mac, you'll receive the audio and send it to your connected speakers.
OMG. It's pretty cool.
You had me at AirPlay and Bluetooth together. How much?
Airfoil for Mac and PC are $29 each for a license that will unlock the full app on multiple computers (but only one user). If you have both Macs and PCs in your house, you can get a 30% discount on a bundle pack for $40.
If you think $29 is a lot of money, think about how cool it would be to play audio from all of your speakers, not just your multi-room paired HomePods. You can connect your Mac to an Echo, a Google Home, a variety of different Bluetooth and AirPlay speakers, and play the same music throughout every nook and cranny of your house.
Airfoil is available as a free trial so you can try before you buy. If you like what it does (and if you have a couple of AirPlay and Bluetooth speaker in the house, you will), you can order the full license right within the app.
I know some of the iMore readers are long-time fans of Airfoil. Let us know what your set up is like and the things you've done with Airfoil.
Updated June 2018: Updated to reflect AirPlay 2 support.