I did a round-up article a good while ago here on the Music App Blog that looked at the various ‘MIDI performance’ apps available for iOS. If your keyboard skills are not so great, or perhaps you just don’t get on with virtual piano keyboards on a touchscreen surface, or maybe you don’t have any skills on a traditional musical instrument, apps such as Chordion, ChordPolyPad, Navichord and a number of others offer some interesting alternative ways to ‘play’ MIDI data into your virtual synth/instrument or DAW/sequencer apps.
A week or so ago, another such app was launched when Dmitry Klochkov released his ChordUp app to on the App Store. ChordUp is a universal app, requires iOS8.0 or later, is a 16MB download and, priced at just UK£2.29, is likely to be within almost everyone’s price range. What’s great about all of these MIDI performance apps is that each offers the user a somewhat different ‘playing’ experience and ChordUp does just that. It’s possible to see where some of the ideas within the app might have been drawn from, but the end result is quite an interesting take on a playable touchscreen interface.
The main screen for ChordUp is a fairly minimalist affair and shows the same features on both iPhone and iPad. I did most of my testing on the former but it scales up to the iPad nicely and, depending upon the dexterity of your fingers, some users may well find the somewhat larger iPad (or even iPad Pro) screen size an advantage… but it is certainly very useable on the iPhone.
On the left-edge are a series of buttons for accessing the app’s key settings (more on these in a minute) but the bulk of the screen is dominated by two panels of 12 buttons. The left-hand (slightly smaller) of these is used to select chords (and just to select them; not actually play them) and the display shows the 12 notes of the chromatic scale (although not in note order; the note arrangement is a little more musical than that).
If you tap and hold on one of these buttons, a further set of buttons appears around your finger with some chord types shown. Sliding your finger to one of those chord types will then select that as the current chord. This is best illustrated with an example. So, for example, if I tapped on the A button, I’d be selecting the A major chord by default but, if I then slide my figure to one of the pop-up buttons, I can change that chord selection to some other variant of A – Am, A7, Asus2, Asus4, etc. – but always with A as the root note. The same would apply if I tapped on E; E major by default and then slide to pick an E variant.
This ‘chord picking panel’ is not a million miles away from how chord selection works within Guitarism with the obvious difference being that you (a) always start with the major chord and (b) instead of Guitarism’s ‘tilting’ mechanism to access some additional chords, ChordUp offers this pop-up ring of different chord types.
While Guitarism then has a set of virtual strings that you can then strum or ‘pick’ to play notes from the selected chord, in ChordUp that’s where the larger of the two sets of 12 buttons comes in. Once your have picked a chord using the left-side chord selection pads, if you tap any of the 12 buttons on the right-side group, you trigger a single note from within that chord. This area is, however, polyphonic, in that you can actually tap more than one button to trigger several notes from within the chord at the same time.
The note mapping used here is quite clever. Obviously, with 12 buttons, and only 3 or 4 notes in your average basic chord type, there is some duplication of notes; for example, for a C major chord, more than one button will, therefore, play a C note. However, the buttons are automatically mapped across the MIDI note range so, the three darker buttons in the bottom row are mapped (by default) somewhere in the C3 to C4 range (you can adjust this with the up/down arrows in the left-side settings buttons). Within the nine lighter grey buttons, the left vertical column of three buttons are mapped in the next octave up, the middle column of three buttons a further octave up and the right-side three buttons yet a further octave up (around C6 to C7). Having selected your basic chord, therefore, this second pad of 12 buttons allows you to voice that chord (or notes from that chord) in almost any fashion that you like.
This is actually a rather clever arrangement…. and, usefully, the app’s help pages provide an example of this mapping for a C major chord (it is automatically adjusted for different chord types but the basic pattern remains the same).
So, what we have here is a system that, with one hand you can pick a chord type and, with the other, you can trigger notes from that chord in almost any combination, and position within the MIDI note range, that you might like.
What’s on the menu?
Aside from the octave shift buttons, the strip of menu controls allows you to (from top to bottom) access the settings/help section (you can adjust the size of the pads here if you wish), chose between using the app’s internal sound sources or an external app sound source (that is, send the MIDI data to another app), adjust the volume, reverb and cutoff settings if using an internal sound, and engage the sustain pedal option.
The internal sounds include a few piano, organ and synths sounds and, while basic, are perfectly good enough for noodling around on while you get used to the app. However, I suspect most users will soon be selecting the MIDI out option and picking a suitable MIDI destination for the note data generated.
Play with me
From a technical perspective, I didn’t have any problems getting other apps to recognise MIDI data from ChordUp and perhaps the only technical issue to note is that there is no velocity based response here; all the MIDI notes go out with the same MIDI velocity to your external synth/virtual instrument. That said, once you get used to the combination of chord selection and note triggering, you can create some very expressive melodic or chordal performances. Indeed, check out the two demo videos below to see some examples of that.
However, the flexibility offered here does come with a bit of a price; there is a (short) learning curve in using the interface and the results are perhaps not quite as instant as something like Chordion…. although you do get more control over how you voice your chords and can more easily combine chords and melody.
A couple of additional practical points are also worth noting. First, once you are holding a chord selection on the left panel, that selection only becomes ‘active’ once you trigger the next note in the right panel. However, once you have triggered that first note from the newly selected chord, you can remove your finger from the left panel and the chord will stay selected until you pick a different one. There is a bit of practice required here to get this technigue under your belt but it soon becomes second nature.
Second, I did fumble a little in trying to find a comfortable way to hold my iPhone when using ChordUp. The demo videos below suggest someone holding the phone in front of them and I’m sure that might work with a bit of practice (and getting your iPhone to stop flipping display orientations as you move around). However, when starting out, I simply found it easier to place my iPhone on a desk surface and play down from above. Again, just be prepared for the fact that a little practice and/or experimentation may be required on first use until you work out what’s best for you.
That warning about a short learning curve aside, once you give ChordUp a bit of your attention, it is possible to coax some rather good performance results out of it. The demo videos below do a much better job that I’m capable of after my short testing period but the potential is obvious and, whether it’s full chords, melody lines or repeated arpeggiated note patterns, the combination of chord selection and note triggering works very well.
I’ve no idea whether it might be possible to add some sort of velocity response to the app at some stage thanks to the 3D Touch technology built into the latest iPhones but, if so, that would make a great addition. Otherwise, with the qualifier that you might need to put in a little practice to start with, ChordUp is a neat little utility app and, if you enjoy the options provided by some of the other iOS MIDI performance apps out there, this latest addition is well worth its pocket money price tag to add to the MIDI app tool kit.