Nu Desine AlphaSphere

If you fancy a break from traditional musical interfaces, or merely want a fetching accessory for the dashboard of your spaceship, the AlphaSphere could be just the thing.

It's easy to get a little blasé in the music technology scene: we see endless plug-ins and audio hardware products mimicking traditional designs, vintage instruments, or one another, and one often yearns for a company somewhere to do something that's a little more, well, bizarre.

Bizarreness comes in many varieties, from unco-ordinated and off-the-wall at one end of the spectrum to unconventional but highly focussed at the other, where the motivation seems to be a determination to buck trends and do something genuinely innovative. Under that heading would come the object sitting on my desk, a musical interface which gives the initial impression of a being a football designed by aliens. This object is called the AlphaSphere.

The AlphaSphere is the brainchild of a small Bristol-based company called Nu Desine, who specialise in design projects combining hardware and software.The design-driven aesthetic of the AlphaSphere is obvious — the thing is visually quite stunning — but, as we'll see, the physical device itself is only half of the package: the performance software, called AlphaLive, is key to making the AlphaSphere into an instrument.

Physically, the AlphaSphere is a spherical arrangement of circular touch pads measuring about 25cm in diameter. The pads (or rather, the frames which contain them) are interlocked to form the AlphaSphere itself, which is otherwise hollow, apart from a mass of internal wiring attaching each of the pads to the device's base. The layout of the pads makes the whole thing look at first glance like a geodesic dome, but closer inspection reveals a more subtle arrangement: viewed as a globe, the pads get smaller from what I'll call the equator towards the poles, presenting six rings of latitude each containing eight pads. The equatorial pads are roughly beer-mat sized, while the polar ones forming a ring at the top are each just big enough for one finger. (There's no corresponding ring at the bottom because the base is in the way.)

There are two models of AlphaSphere: the Nexus and the Elite. The two look identical, but the Elite (under review here) comes equipped with a small panel of three buttons and two infinite encoders set into the base, and a MIDI Out socket on the back. The Elite is also available in black, which looks quite the business, especially when it's plugged in, when an eerie blue glow emerges from within. (The internal lighting actually changes colour when the instrument is played.)

In addition to the USB port found on both the Elite and Nexus models, the former also features a MIDI Out port.

Getting Started

The AlphaSphere hardware is purely a controller, and requires the AlphaLive performance software in order to do anything interesting, although if you really wanted to roll your own software you could: the AlphaSphere is a USB HID-class device (the same category as game controllers). I plugged it into Cycling '74's Max and, sure enough, pressing the pads generated a stream of HID messages, but despite the MIDI port on the back, and the fact that it appears as a MIDI device to the operating system, the AlphaSphere doesn't generate MIDI without the help of AlphaLive. So I installed AlphaLive and its bundled sample libraries and fired it up.

The AlphaSphere's pads look rather like drumskins,but have a rather squidgy feel: in fact, each pad's membrane is stretched over foam rubber encased in its frame, and triggers magnetically. (The membranes are replaceable.) The initial preset in AlphaLive sets the pads up to trigger notes in a major scale, so it's easy to get an early impression of the AlphaSphere's playability. With AlphaLive's sample buffer size turned right down to 16 samples, note triggering was lightning fast, and dynamically responsive. AlphaSphere's pads sense pressure, so other presets map pressure to filter and effects control, providing polyphonic touch sensitivity that is, again, fast and responsive. We'll look at pressure control later, but suffice to say that the AlphaSphere and AlphaLive offer polyphonic control that's rare in the world of instrument plug-ins and channel-pressure keyboards.

1: The AlphaLive application: part editor, part instrument.

AlphaLive

It's time to look at AlphaLive more closely, since it's intended to serve as the centre of activity for the AlphaSphere. In basic terms, AlphaLive is an editor for assigning functions and mappings to the AlphaSphere's pads, but it also provides MIDI interfacing, audio playback and a rather novel sequencing engine, making it part editor and part instrument. The inclusion of an audio engine and sequencer might seem a bit strange, given that prospective users almost certainly have their own DAW and instrument plug-ins already, but the strategy makes some sense: the AlphaSphere provides multiple independent streams of pressure data, which is something MIDI software handles poorly (hands up: does your DAW accept polyphonic aftertouch?), while the HID interface allows for 9-bit data, rather than MIDI's 7 bits, for potentially higher resolution. AlphaLive's sequencer also performs a few tricks not found in mainstream programs.

Launch AlphaLive, and you'll be presented with a screen looking something like screenshot 1, which at first glance might be mistaken for the head-up display in Tony Stark's Iron Man armour. It's probably safe to say that Nu Desine like circles: pretty much the entire interface is built from circular icons and interface elements, with the exception of some text fields. To some extent, this makes sense: the AlphaSphere is spherical, so representing it radially on screen seems appropriate, while loop-based sequencing lends itself to a similar representation. Other design elements seem to be curved just for the sake of it, although on the whole I don't think that affects the ergonomics too badly. AlphaLive's single-window interface presents two discs: the main, left-hand disc — called the 'layout' — is a projected view of the AlphaSphere's pads, with the 'north pole' at the centre and the lowest pads arrayed around the perimeter, while the smaller right-hand ('pad settings') disc is a set of controls for assigning functions to the pads themselves. The layout disc is skirted by a keyboard, for setting and viewing note pitch assignments. Finally, a left-hand column of buttons allows for switching between complete setups — 'scenes' — for the AlphaSphere. (Scenes are numbered, but not named.)

2: The sample loop attached to a pad, displayed in a ring.

Despite the unconventional layout, the software presents a fairly conventional editing process: select a pad, or pads, in the layout disc and edit their settings in the settings disc. We'll look at the settings in more detail shortly, but the general scheme isthat each pad can be in one of a number of modes: MIDI, sample playback, sequencing, or control output. (The pads are displayed in slightly different colours depending on mode, although the colouration is subtle and hard to distinguish.)

It's possible to select a number of discs — an entire row, say, or a specific sequence in order — and edit them as a group. Alternatively, the pad settings can be completely heterogeneous, a random mix of MIDI and sample triggering in arbitrary pitches, alongside looping and sequencing. AlphaLive isn't particularly illuminating about the pad settings as a whole: you have to click a pad on screen to see its details. The main layout display would benefit from some additional hints to provide at-a-glance information about the entire set of pads.

One drawback of the AlphaLive became apparent after some editing: there's no undo function, and as the scene auto-saving is turned on by default, you risk losing configuration information that you might have wanted to keep. I think undo would be an essential feature for an update. (Nu Desine tell me they're planning to add it in version 2.)

The first AlphaLive preset configures the AlphaSphere into its closest approximation of a keyboard, playing notes in a sampled synthesizer tone. The large pad at the front of the AlphaSphere (by 'front' I mean the side where the encoders and buttons are located on the base) plays a note in C, and traversing the large pads from left to right (or, viewed from the top, anticlockwise) results in a major scale. The ring of pads above these present a scale an octave higher, and shifted anticlockwise, so it's possible to play six octaves of major scales in sequence on the AlphaSphere by triggering pads one ring at a time, jumping to the next ring up when needed. Since the pads are different sizes, not to mention pointing in different directions, you're unlikely to get an even playing technique (it probably makes much more sense to dedicate each pad ring to a different sound or function) and since the AlphaSphere is, well, a sphere, you can't necessarily see what you're playing. As there are only eight pads per ring, though, you can pretty much navigate by touch alone.

Working With Samples

AlphaLive can operate as a fairly conventional, if rather primitive, sample player. Once a pad is in sampler mode (done by clicking the waveform icon at the top of the pad display), you can select, or drag-and-drop, an audio file and you're good to go. There are two possible sub-displays in the settings area: trigger (to set sample and triggering parameters) and pressure (to configure pressure-sensitive effects).

3: An entire ring of pads is selected in one click and mapped to one of the preset scales.

If you're expecting the kinds of editing features common in sample-player plug-ins, you're going to be disappointed. There's no editing of start, end or loop points (although you can set attack and release times), no layering or crossfading, not even a control for pitch alteration. (The sample-based preset described above has one cropped and tuned sample per pad.) On the other hand, there's a selection of triggering modes: sample playback can be toggled or latched, there's a time-quantise feature to synchronise triggering with a global clock, and sample playback can be looped. (The waveform is displayed in a ring, as shown in screen 2.) Pads can also be placed into exclusive groups — like those found in some drum machines — so that one pad can cancel the playback of another in the same group. AlphaLive comes with a selection of rhythm and drum loops, and careful setting of the playback options allows for some interesting — and fun — loop-based performance techniques, but if you go down this road you'll hit another drawback: AlphaLive doesn't do any kind of time-stretching, so sample loops are hard-wired to particular playback tempos.

On the plus side, though, AlphaLive's sample player provides effects processing with real-time control, and the effects processing is polyphonic: every pad has its own effects, controlled by pad pressure. The available effects programs are pretty conventional: filters (low-, high- and band-pass), two distortion algorithms, delay/echo, reverb, flange, tremolo. Only one effect can be active per pad at any time. Each effect has a selection of parameters — they all have wet/dry mix — and the pad pressure response can be scaled and applied to any single parameter. The effects sound reasonable and work well — in particular, thelow-pass filter gives pretty expressive polyphonic dynamics to percussion sounds — but for sophisticated processing you'll have to look at something external to AlphaLive (and forego the polyphonic processing).

Although AlphaLive performed well when I tried triggering effects on several pads at once, the software doesn't have any indicator for DSP load, so there's no way to know how much processing you can pile into a preset scene before hearing audio glitches.

Working With MIDI

Switch a pad from sampler to MIDI mode and the layout and settings displays change. The curved keyboard around the layout becomes active, allowing the MIDI note for the pad to be selected. The process of individually setting the pitch of each pad would be pretty cumbersome, but AlphaLive provides some clever shortcuts. Multiple pads can be selected — for example, one selects an entire ring with one click in the space between two adjacent pads (as we've done in screen 3) — and then a preset scale can be applied to them, ascending in the selection order. (Scales range from the conventional Western set to Hungarian and Indian pitch selections.) Alternatively, you can command- or control-click notes to assign them to the pads in sequence. Alt-clicking the keyboard allows the entire set of currently highlighted note assignments to be transposed chromatically.

The pad-triggering options for MIDI notes are much the same as for samples, although the looping options are absent. The pressure settings allow pressure to be mapped to MIDI controller, aftertouch (mono or poly), or pitch-bend (up or down). MIDI is not particularly well suited to any kind of keyboard that can send independent controller streams per note — the only kind of control supported is polyphonic aftertouch, which as I've noted isn't recognised by many DAWs out there — so to use another, monophonic, controller such as pitch-bend or mod wheel, pads have to be assigned different MIDI channels. I verified that polyphonic aftertouch and monophonic controller data were transmitted as expected, but I was expecting AlphaLive to borrow a trick seen on the polytouch keyboards of the 1990s: when several keys generated polyphonic controller streams, the monophonic output would be the maximum value from all the keys. In AlphaLive, values for the same MIDI controller from different pads on the same MIDI channel will interfere. I'm sure this is something that could be addressed in a software update.

Sequencing

In sequencer mode, a pad controls a 32-step sequencer, displayed as a disc, supporting 12 possible pitch values. Just as a (non-sequencing) pad can be in MIDI or sampler mode, so a sequencing pad can either generate MIDI from its sequenced notes, or trigger samples. In sequencer MIDI mode, the 12 pitch positions of a sequence can be assigned a preset scale — which can be transposed — or the pitches can be assigned individually. MIDI velocities can be edited, as can the sequence length. Pad pressure can be assigned to various4: A step sequence laid out for editing in a circular grid. MIDI controllers, as in the non-sequenced MIDI mode. (Rather disappointingly, pressure can't be assigned to modify note velocities.)

In sequencer sampler mode, each sequence 'pitch' triggers its own sample, which can be dragged-and-dropped as an audio file. (AlphaLive ships with a number of preset sampled drum kits, as well as demo sequences for them.) Pad pressure can then control audio effects, as in the non-sequenced sampler mode.

So far, so conventional, but AlphaLive has a rather clever feature hidden behind a button called Pressure Link. Turn this on, and a pad's pressure is mapped to dynamically switch between multiple sequences for that pad. The sequences — of which there can be up to eight — have the same length, pitches and tempo division, but distinct sets of notes, and pressing on a pad scans up or down the sequence list, activating and deactivating the different sequence patterns on the fly. This feature works for both MIDI and sample sequences, and allows for some interesting performance options: add layers to a sequence by applying pressure, or shift between sequences with minor differences to incorporate various kinds of articulation. Bearing in mind that every pad can have its own stack of sequences, the control opportunities are extensive, to say the least.

Pads in sequencer mode support recording: activate the Record Mode button, and the sequence will pick up notes triggered by other pads if they match the note assignments for the sequence. This works in MIDI mode, if the MIDI channels and pitches match; cleverly, recording will also work for sample sequences. I was half hoping that this might be some kind of audio looping, but it's very similar to MIDI recording: notes match if they trigger the same sequence file. Perhaps thankfully, it doesn't seem to be possible to bounce notes from one sequence into another.

Recording is a handy way to generate new patterns, especially while improvising, but the features are a little limited:notes have to be deleted with a mouse click (they record in overdub mode only) and there's no pressure-sensitive roll recording, drum machine-style, which is a shame as the AlphaSphere is ideally suited to that kind of gesture.

Conclusions

There are risks and benefits to adopting any radical new instrument or performance system: it is, by definition, non-standard, so you have to decide whether the up-front cost, and the reliance on a single vendor for updates and support, is worth what the product will let you achieve. In the case of the AlphaSphere, you are also locked into the AlphaLive software (unless you are willing to roll your own), so need to be comfortable with what it offers and how it functions.

As a piece of hardware, the AlphaSphere is impressive: it's fast to trigger, sensitive and responsive. It also looks stunning, although the playing technique would take some time to pick up.

AlphaLive is also impressive: the design is striking and appealing, and the essential features are good, as is the way they interact and map onto the hardware. The ability to mix and match sample triggering with MIDI playback and MIDI or sample step sequencing, plus effects, all in the same scene, allows for some interesting hybrid setups. AlphaLive does have some weak areas: setting pad assignments is a bit fiddly, there's no clear overview of the state of the pads as a whole, and — most serious — there's no scope for tempo change or synchronisation with other hardware or software. If you can live with that limitation — or wait for improvements — the AlphaSphere plus AlphaLive combo is a nice piece of work, and deserves to start appearing in front of audiences.