A bit of history here: though the good old fashioned piano keyboard has always been the primary interface for synthesizers, it’s certainly not the only one. The most famous non-piano interface is the theremin, which uses the movement of the performer’s hands through a magnetic field to control pitch and volume.
That’s Leon Theremin, the inventor of the device, demonstrating it.
One of the more fascinating synthesizers is the ondes Martenot, invented in 1928. The Martenot can be played using either a traditional piano keyboard or using a ring tied to a loop of string below the keyboard. You slide the ring back and forth and the pitch corresponds to the key it’s underneath on the keyboard. Pressing a key or moving the ring produces no sound on its own; rather, the volume is controlled by a sort of rocker switch.
It makes more sense if you see and hear it played. It’s a gorgeous, almost unearthly instrument.
The Martenot is a favorite instrument of Radiohead’s Jonny Greenwood, who is one of the few modern experts on the device. There aren’t very many of them, and you could probably buy a nice car for what you’d pay for one nowadays.
A similar input, used on a very few obscure synths, is a ribbon controller, which replaces the ring with a reactive ribbon; you place your finger on the ribbon and it breaks the circuit, generating a specific frequency. You can buy these to add on to old analog synths or as MIDI controllers.
Ribbon controllers tend to be expensive — not as expensive as an ondes Martenot, but I usually see them for a few hundred dollars. Outside my budget for something I’d only use rarely.
Which brings us back to the iPad. The iPad has a touch screen, which means it can very easily be used as a virtual ribbon controller. Beyond that, though, there have been several software instruments designed for the iPad and iPhone which take even better advantage of the device’s interface.
My current favorite is Bebot. Bebot is a small synth app that displays a cute robot on screen. As you touch the screen in various places, the robot “sings” the note you’re playing. Sounds like a toy, right? But in fact, Bebot is a deceptively powerful little synth. Moving your fingers along the X axis of the screen controls pitch; depending upon which synth voice you’re using, Y axis controls either volume or filter. Here’s a dude messing around with it on the iPad.
A simple tool, but it’s capable of some fairly beautiful output. The only drawback to Bebot is that you can’t record within the app; you need to output it into something else.
Bebot can “autotune” your playing to discrete Western half-tone notes (or whatever scale you choose; you can make Bebot only play in E-minor, for example, by selecting the notes used in the preferences panel). Or, like an ondes Martenot, you can use it as a continuous controller, gliding from note to note, using the onscreen grid or your own ears as a guide. Combine this with the ability to control the velocity of your note by sliding up and down, and you’ve got something that’s most equivalent to a fretless bowed string instrument like a cello or violin. Bebot sounds nothing like these instruments…but you could play a violin piece fairly convincingly on it.
My current favorite music app, Nanostudio, has an on-screen piano keyboard to control its built-in Eden synth (of which you can have four simultaneous instances playing). But it’s not physical, it’s just pixels on the screen…meaning you can slide back and forth between notes as you would on a ribbon controller. I’ve discovered that if you set the Eden to monophonic (meaning you can only play a single note at a time) with portamento (meaning one note “slides” to the next”), you can get something that, with a little practice, approximates a continuous controller. What I like is that the glide only happens when you hold notes down; you can still get normal instant notes by playing staccato.
Here’s a snippet of my first attempt at this: a cover of Talking Heads’ “This Must Be The Place (Naive Melody)”. I’ve gotten a bit better at using the Eden since this, but I think this is a cool first attempt. Listen for the synth solo at about 24 seconds in.
I’m really excited about MorphWiz, an instrument endorsed by keyboardist Jordan Rudess of prog-metal outfit Dream Theater. (Not a band I listen to, but the guy’s certainly a talented musician.) It looks a lot like Bebot on crack, adding recording and looping capabilities as well as “morphing” from waveform to waveform.
The interface is a bit Heavy Metal for my taste, but I can deal with that if it works. I’m convinced, deep down, that all synths are meant to be ugly.
If I come up with anything really cool using these tools, I’ll post it up so you can hear my progress.