Capo—or any other application—cannot work with songs that are protected by DRM (Digital Rights Management).
Songs that you download from the streaming catalog on Apple Music are all protected by DRM, and therefore Capo cannot access the audio data to analyze and manipulate audio for playback.
Fortunately, it's pretty easy to get a DRM-free copy of the songs in the streaming catalog.
"Upgrading" your streaming music
By purchasing the songs you want to learn from the iTunes Store, you get a DRM-free copy that Capo can access for its processing and analysis.
Of course, the benefits of owning DRM-free music don't end at using them with Capo!
- Other apps will also be able to access the songs you buy
- You can copy DRM-free songs to an SD card or USB drive
- You can burn DRM-free songs to a CD from iTunes
While the latter two benefits seem archaic, there are plenty of devices out there (cars, older AV equipment, etc.) that are awkward to use with an iPhone plugged in. (Yes, there are even people that have to connect things with physical wires to get sound to play!)
Buying from an iPhone or iPad
Capo offers a way for you to quickly convert songs in your Apple Music collection to a DRM-free copy by purchasing them from the iTunes Store.
When you select a song that is unavailable to Capo, you can choose to go directly to the iTunes Store app where you can purchase the song you wish to learn.
Once purchased, you can bounce back to Capo and a project will begin its processing and analysis immediately.
Buying from a Mac
This is easy to do straight from iTunes. Just right-click or control-click on the song you want to learn, and choose "Show in iTunes Store". Purchase the track, and then you can drag it into Capo to begin processing and learning the song.
Should you skip the Apple Music subscription, and buy everything instead?
In our opinion, no!
An Apple Music subscription is an excellent way to discover new music, and it's much cheaper than having to buy every single song and album that you ever felt like listening to.
There are also plenty of songs that we are happy to listen to, but we don't feel the urge to learn how to play every single one. But every so often, a song comes along in an obscure playlist that grips you, and you just want to sink your teeth into it.
Whenever inspiration strikes: just spend the buck, get the song into Capo, and enjoy the fulfilling experience of digging deeper into whatever it that got you hooked in the first place!