The iPad should make for a terrible musical instrument. As marvelous as it can be for everyday tasks, the small-ish multitouch screen lacks the tactile feedback you normally get when you play music. But once I started looking into some of the music-making apps and devices that you could mate to iOS, I realized the iPad may not be much of an instrument—but it could be the most versatile musical "brain" ever created.
My moment of clarity happened recently, while unpacking the Akai SynthStation49 from its box. I plugged it in, and pulled out my iPad and docked it in the device's tablet tray above the row of black-and-white piano-style keys. Right out of the box, the SynthStation looks like any basic synthesizer keyboard. It has keys, knobs, and square rubber pads for playing drum beats or samples. But if you plug it into the wall and start playing, you'll hear nothing. That's because this thing isn't running any software. No tones are pre-programmed into it. It's just a soulless skeleton that knows no sounds of its own.
That's where the iPad comes in. Once the the tablet is affixed to the SynthStation's 30-pin connector, it comes alive. Suddenly, the carcass has a brain and the sounds it can make are limited only by the collective imagination of music app developers everywhere.
Indeed, without robust music apps, devices like the SynthStation would not be all that interesting. Fortunately, iOS developers have built some pretty complex and incredible things for iPad-toting musicians, and the Android ecosystem is not far behind.
Take Korg's iPolysix iPad app, for example. It packs the the interface of a real, 1980s-era polyphonic synthesizer—with its rows of knobs and buttons for tweaking every sonic nuance—into the 10-inch (or 7-inch, if you've got a Mini) screen of an iPad. Like a real synthesizer, its bank of dozens of pre-built sounds can be endlessly tweaked and layered with effects and the new ones you create can be saved for later. The iPolysix app also packs in a drum machine, mixer, and sequencer for recording multiple tracks. Much more than just a synthesizer, it's a mini-studio for creating multi-track synth songs from the iPad. The results can be exported as WAV files, uploaded to SoundCloud, or wirelessly synced with nearby iOS devices using Korg's own WIST standard.
The further into the iPolysix app's initially intimidating interface you delve, the more its $30 price tag starts to make sense. The same is true of the iMS-20, an equally pricey (but even more complex) app from Korg that replicates the functionality of a vintage analog synthesizer and sequencer, complete with virtual patch cables and no fewer than 35 knobs. Apps like these sport complex UIs that normally fit onto sizable synthesizer consoles, but that have somehow been squished onto the screen of a tablet. In the case of the iMS-20, each component of the interface can be zoomed in upon to maximize—or as it sometimes feels, enable—usability.
Synth apps like these are incredibly complex and impressive. A true testament to the power of iOS as a software development platform. But they remain, by default, trapped inside a form factor that doesn't lend itself all that well to forming piano chords or twiddling knobs. At the end of the day, the tactile feedback of a physical interface is still necessary in some cases. This is one of them. And that's why devices like the SynthStation49 are so useful.
The physical keys, pads, and knobs of the SynthStation don't map one-for-one to the virtual UI of an app like the iPolysix or iMS-20. Far from it. Indeed, when you play either of Korg's flagship synth apps from the SynthStation, all you're really getting is a physical keyboard upon which to play notes and chords, as well as modulation and pitch wheels, drum machine pads, and a few other basic physical knobs. But by breaking the keyboard interface free from the confines of the iPad's glass screen, it not only makes playing chords far less tedious, but it frees up that screen for more appropriate types of user inputs: turning virtual knobs, selecting sounds, adjusting settings, and generating tones by moving your finger around on the app's Kaoss pads. Suddenly, the interface is split into two: physical keys and buttons for the things that most require them, plus a multi-touch screen for tasks that don't feel cumbersome when you put your fingers to glass.
There are plenty of other, less complex music apps available for iOS and most of the keyboard-based virtual instruments in the App Store will work perfectly with the SynthStation or a device like it. Apple's GarageBand app alone features a ton of pianos, synthesizers, and other virtual instruments that can be played via an external controller. GarageBand's built-in drum machine can also be controlled using the rectangular rubber pads found at the top of the SynthStation (and presumably any other MIDI-enabled controller with such pads). Animoog, a widely beloved and rather impressive synth app from Moog, suddenly turns from an app into something resembling a real synthesizer once it's docked into an external controller. Like the Korg apps, it sounds indistinguishable from physical, far more expensive synthesizers.
The split tactile/multitouch music interface has some advantages inherent in the way iOS itself works. For example, a four-finger swipe across the screen lets you instantly jump from app to app. That means you can play one part using the Animoog app and then swap it out with the iPolysix without fidgeting with the home button. Thanks to iOS's multitasking, you can even play sounds from multiple apps simultaneously. For instance, if you set the iMS-20 app or GarageBand to be controlled via the SynthStation and tell the Animoog app to be controlled natively, you can play both at the same time. Likewise, you can use the external controller to play a keyboard-based instrument app in the background and then pull up another, multitouch-centric music app to be played simultaneously on the screen. Of course, there's far more you could do once you pair this set up with other instruments, pedals, and devices, but the scope of capabilities presented solely by the iPad and an external device like the SynthStation is pretty mind-blowing.
One of the first and most novel use cases for the iPad was as a virtual piano and tool for teaching music. As the hardware has grown more powerful and the development platform has matured, the possibilities for iOS musicians have been slowly expanding. Perhaps the biggest push forward for mobile music app developers was the inclusion of the CoreMIDI framework in iOS 4.2. Using the CoreMIDI APIs, developers can build MIDI support into apps and enable their software to talk to external devices via the iPad Camera Connection Kit (which turns the power cord slot into a USB port) or another third-party accessory. In iOS 7, the state of iOS music-making will step forward once again with the introduction of support for inter-app audio.
Of course, Akai's SynthStation is not the first device to pair with iPads and iPhones to enhance the creation, performance, and production of music. There's a long list of adapters, audio interfaces, MIDI controllers, and other devices that can plug into the 30-pin or Lightning connector port on an iOS device and control music apps or turn the iPad into part of a full-blown studio environment.
What's different about the SynthStation and its counterparts is primarily in its design: Instead of plugging into the iPad, the iPad plugs into it. Something about docking the iPad into the device makes it feel less like an accessory and more like an actual instrument, with the iPad acting as the sonic brains of the operation, slanted at a angle convenient for as-needed multi-touch interaction.
For music hardware developers, teaming up with the iPad is a smart move. It allows them to focus on building a physical interface for playing music while effectively outsourcing the software smarts to Apple and its distributed team of iOS developers. It reduces the costs of production while giving consumers a versatile, virtually limitless musical instrument. The SynthStation is a solid example of this concept for keyboard-based instruments. The same idea has been applied to effects pedal boards for guitarists and DJ turntable setups. By the end of the year, Starr Labs expects to start shipping the iTar, a MIDI guitar controller for the iPad that debuted on Kickstarter in 2011.
We have yet to reach a point at which phones and tablets are a mainstay of onstage set ups for musicians, but mobile music creation is becoming more common and a growing selection of third-party hardware is helping to push the practice toward normalcy.