The Wireless Future of Music
A big new feature of the DrumPants 2.0 Wearable Drum Machine is that it now works with Apple’s MIDI over BLE, built-in natively to iOS and OS X. In typical Apple style, this eliminates the myriad cables and ports that musicians are constantly dealing with, and gives you wireless control over music software like Abelton Live, GarageBand, and FL Studio. Just turn on your instrument, turn on your laptop, and you’re done. No cables or adapters or power supplies to fuss with.
Using Apple’s open protocol allows the DrumPants to get the lowest wireless latency possible* on a Mac, making them much more responsive than the DrumPants 1.0 (which were built before Apple released their spec).
As our test users have been using Apple’s native Bluetooth MIDI interface in live performance situations, we’ve compiled a few of their suggestions on how it can be made more seamless and robust:
Autoconnect
An important feature users requested early on in the DrumPants app is to automatically reconnect to the MIDI instrument if the connection is lost. The musician could have wandered out of Bluetooth range, or turned their DrumPants off to save power until they needed them, but musicians expect an instrument to be usable as soon as they turn it on. iOS and Mac should be periodically scanning for any available instruments and reconnect if they were previously connected.
Now, one caveat we found is that if you give your extra DrumPants to a friend, and they try to connect with their app, your app’s autoconnect might “steal” the connection before their device sees it. In this case, manually clicking the “Disconnect” button in the Audio MIDI Setup should cancel any autoconnection option, so other devices have a chance to connect to the instrument.
Same Treatment as a “Wired” MIDI Instrument
Right now, to use MIDI over BLE with iOS, you need a 3rd party app like midimittr to translate. This means that your BLE instrument is a virtual midi instrument, which for some reason is not as respected as a physically-connected USB MIDI instrument (e.g. doesn’t work in GarageBand). Yes, the iOS SDK has a separate interface for connecting BLE instruments that developers can elect to integrate into their apps, but they shouldn’t have to if they already support CoreMIDI!
I’d like to see one central location in iOS where you can manage your BLE instruments, and once connected, they should appear to other apps as a bona-fide, plugged-in, CoreMIDI instrument — treated no differently than the “wireds” on those clunky old USB adapters.
This way, all music apps that already support CoreMIDI instruments can use the BLE ones automatically. This is already how it works on OS X, so I’m guessing the iOS equivalent will be here soon.
The Latency Arms Race
Although the connection latency is quite good and barely noticeable unless playing a ton of notes at once, it’s literally not as good as it could be.
Apple’s spec limits the connection interval to 10ms on OS X, and 15ms on iOS. Now, this is amazingly good (10ms is at the edge of being noticeable to experienced musicians) — and much faster than the 55–80ms of a touchscreen — however, the official Bluetooth Low Energy spec allows for connection intervals as low as 7.5ms! That’s almost 25% faster than OS X, and twice the speed of iOS! The DrumPants Android app fares better: it can connect at 7.5ms on some Android devices.
Apple’s reasoning is that connecting at the fastest interval drains the battery more quickly, and it can also slow down the Wifi connection (since they are on a shared chip). Apple is insistent on preserving the user experience for other apps — even though a musician would prefer to have the most responsive experience possible, at the expense of their web-browsing and emailing capability (which they shouldn’t be doing at a show!)
I think Apple could solve this gracefully by connecting at the fastest 7.5ms interval only when the device is plugged in. That way, there’s no worry about battery drain, and musicians can be assured they’re getting the best performance simply by charging their iPad when performing.
Untethered Possibilities
Other than those main considerations for high-pressure, live performance situations, the experience Apple has made is solid. Once the DrumPants are connected and set up with an app, the connection is fast, reliable, and jitter-free, even from pretty large distances in large crowds. I’ve performed with them walking up to the stage from the back of the venue, and they played every note as I meandered through the EM-soaked, signal-absorbing bodies of the audience!
Playing other wireless musical instruments like the JamStik and Livid Instruments’ Guitar Wing gives us a glimpse at the future of music tech, and it is an exciting one! At DrumPants, we’re committed to this vision of the future, and so we are releasing all our Bluetooth firmware as open-source. We hope this will provide a solid base for the DIY community to create their own wireless musical instruments, and really push the envelope up!
To support our vision, see professional musicians playing wireless music, and get your own pair of DrumPants, please check out the DrumPants 2.0 IndieGoGo Campaign.
