Chapter 6: New Instruments
On post-keyboard interfaces and custom controllers
In the iOS music world, most synth apps offer a standard keyboard interface, and many will support the use of an external hardware keyboard controller. In addition, many apps offer alternatives to the traditional interface, ranging from subtle variations to completely new controller designs.
Post-Keyboard Interfaces
A common option within many synth apps is the ability to define a specific key and scale, resulting in a custom keyboard layout that makes improvisation easier due to the absence of unwanted notes.
When looking at configurable keyboards, a major consideration (at least for me) is the flexibility of scale definition. Many apps will offer a handful of common scales, which can be very restrictive if you’re working outside the traditional western major/minor system. Others provide longer lists of scales, but the best implementations are those that allow you to define custom scales by manually choosing the notes to include.
Animoog Z
In my opinion, Animoog Z offers one of the best keyboard-like interfaces with full custom scale support. Animoog Z sounds great itself, but it can also send MIDI to control other apps in the background. You can save custom keyboard configurations with each preset, or lock the current scale in place so you can change presets while keeping the current configuration. Moog’s Model 15 app offers this same functionality.
GeoShred
Another favorite app for custom control surfaces is GeoShred. The GeoShred interface is closer to guitar than keyboard, and offers many flexible options for setting up the interface, including custom tunings, ascending and descending intervals, and alternate temperament. You can also set up a diatonic surface like Animoog Z where only the desired notes are available.
ThumbJam
ThumbJam is a great post-keyboard app which has been around for quite a while. Besides offering customizable scales and tunings, ThumbJam was one of the first apps to put the motion sensors to good use, allowing you to use horizontal and vertical tilt motions to control volume, pan, and pitch bend. ThumbJam also allows you to split up the control surface to control up to four different instruments, each potentially with their own custom scale. As with the other apps mentioned in this section, ThumbJam can also be used to control other apps via MIDI.
Gestrument Pro
While many of the touchpad interface apps use the horizontal (x) axis for pitch and the vertical (y) axis for things like volume or pan, Gestrument Pro by Jesper Nordin takes a different approach by mapping the y-axis to pitch (although not necessarily linearly) and the x-axis to note duration values. Gestrument Pro has 16 instrument channels, which can each be assigned to a range of note pitches and durations, causing them to react differently to the location of your touch on the playing surface in relation to up to 8 cursors. Gestrument also supports adjustable degrees of randomness for the rhythm and pulse via each instrument’s rhythm generator, providing more fluid movement to the different voices.
Going beyond full custom 12-note scales, Gestrument Pro enables microtonal scales by allowing you to edit each pitch in cents or as an intervallic ratio. Scales can span up to two octaves, but don’t necessarily have to repeat on a standard octave if you want to get really creative. You can also import a MIDI file to use as a scale, or import a scale from the companion app ScaleGen. ScaleGen can also generate scala files, which can be exported to ThumbJam.
Gestrument Pro can also send MIDI CC messages based on the X/Y positions of the cursors, which opens up some interesting control options.
Roll Your Own Controller
Moving beyond playing notes, there are a couple of apps that excel in creating robust MIDI control interfaces for controlling parameters in other apps via MIDI CC messages.
TC-Data
The most advanced (and sci-fi cool) controller interfaces on iOS are shared by Bit Shape Software‘s TC-11 and TC-Data. TC-11 is a modular synth and TC-Data is a dedicated MIDI / OSC controller. Each preset for these apps is an instrument in itself, giving the user full control over how the app reacts to multiple touches and device motion based on over 300 different controllers and triggers. TC-Data can send MIDI note and CC data while targeting specific apps and/or channels. Both apps will react to everything from the distance between touches to the exact orientation of the device in 3D space. You could even create a preset for road trips, which would react to your speed and compass heading.
Midi Designer Pro
With the unfortunate demise of Lemur, Midi Designer Pro ascended as the king of custom midi interface designers for iOS. It lacks scripting capability, but it’s intuitive and user-friendly when it comes to lining up your control objects. If you’re using your iPhone as a midi controller, this is the only app that supports building interfaces directly on your phone.
Feel free to leave a comment if this has been useful, or especially if I’ve missed or misrepresented anything.