You are here

Interactive Light Dimension

Beam MIDI Controller
Published June 1997

The Dimension Beam translates physical movement into MIDI data, offering theremin‑style control over your keyboard rack. Dominic Hawken explores this new device.

Since its inception, MIDI has remained a control protocol best utilised by the keyboard player. Designed as a global standard to allow music‑based products from all manufacturers to interface directly with each other, the MIDI specification has subsequently been developed and expanded to include control over lighting rigs, mixing consoles and many other audio‑ and entertainment‑based systems. Ever since Jean Michel Jarre broadcast his live concert extravaganza from the Docklands Arena in the '80s, using a multi‑coloured, light‑based keyboard that generated sounds according to the position of his hands, a number of manufacturers have been looking at methods of generating MIDI data based on physical movements rather than keyboard skills.

Historically, this idea of sound control has been around for a while. Invented in 1919, the theremin first really came to prominence in the '50s, well before the development of the MIDI standard, and went on to produce the ghostly lead sound on the Beach Boys' 'Good Vibrations' single. It has subsequently established its place in history, championed by modern artists such as Portishead, in the same way that older analogue keyboards have featured so prominently on many of today's dance tracks. The theremin generates two electromagnetic fields; any movement or physical presence within the fields produces a monophonic tone from the instrument, with a pitch and volume based on the position of the presence. With careful practice, a tune can be produced by moving your hands about within the fields. Despite the limitations of the instrument, the theremin has generated a cult following (you can obtain more information from the World Wide Web at www.Nashville.Net/~theremin/, or see the article in November '96's SOS).

The Dimension Beam, loosely speaking, takes the theremin concept and drags it into the '90s, offering the same non‑contact interface but adding a wealth of MIDI parameters; these allow the user to control volume and modulation, as well as basic note and patch data. The result is a complete MIDI controller designed for live and studio use, capable of interfacing directly with the best of today's modern musical technology.

Design And Concept

The Dimension Beam is a small, stand‑alone unit, with a screw‑in connection on the rear for mounting. An accessory pack includes a solid base‑plate that lifts the unit about 30cm from the ground, and another adapter is available to mount the system directly onto a mic stand, but in practice any basic camera tripod will suffice. From the top panel, the unit generates an invisible light‑field — the 'Beam' — and any movement that occurs within this field triggers a MIDI output which can then be sent to a sequencer or keyboard.

A wide range of messages can be programmed, including controller information, as well as standard note data. MIDI settings are accessed via four directional buttons on the front panel, and viewed in a single‑line LCD. The buttons, together with an additional foot‑pedal, also determine the shape of the Beam, and switch through the range of patches and presets. A Mode LED indicates the current state of the unit; an infra‑red sensor and transmitter take care of the physical interface, calculating current movement and positional data. MIDI In and Out/Thru sockets are on the side of the unit, and power is supplied via an external adapter. Usefully, the MIDI input automatically merges any incoming data and streams it to the Out/Thru socket, so it's possible to connect the device in line with your existing master keyboard, without the need for an extra MIDI sequencer input. In practice, while this is fine for moderate usage, streaming large amounts of MIDI data through the unit — doing a sample dump, for instance — at the same time as generating new controller information can actually cause data to be lost, so an external unit is recommended.

The Dimension Beam triggers individual notes a great deal faster than is possible when you're playing a keyboard or MIDI guitar, and some crazy effects can be generated as a result.

The Dimension Beam is supplied with six basic preset patches, each of which may be edited and saved back to one of six further user‑defined memories. Each patch can be set to produce either continuous controller information, or scales of MIDI notes, or a combination of both in which a note is triggered as soon as any initial movement occurs, and further movement produces the control change. A separate MIDI channel and program number can also be defined for each memory, with the program sent as soon as a new patch is selected.

Scale mode streams out note data, and can be configured to default to a wide range of preset scales, ranging from simple chromatic and major through to more obscure settings such as Neapolitan minor and Mixolydian. Selecting a scale appropriate to a given song makes soloing using the Dimension Beam a great deal easier, as the output notes are limited to those that work in harmony with the current key. Controller mode works best when the unit is connected directly in line with a master keyboard, and the beam is used to modify sounds played directly from it. Chords can be played on the keyboard, and the resulting MIDI data pitch‑bent or faded according to hand or body movement within the beam.

Adding a foot‑pedal further enhances the live capability of the unit, with two different 'Freeze' modes available, as well as a movement‑based memory restore. Clicking the pedal freezes the current MIDI note until the pedal is clicked again, or until the beam is manipulated at the same position again. Clicking the pedal from the main menu divides the beam into 12 different sections, each representing a memory preset; moving through the beam then steps through the presets until you select one by clicking the pedal again.

In Use

The Dimension Beam certainly offers a unique way of controlling MIDI hardware. When you first plug in a new unit, it defaults to a basic 'note to position' setting, and your initial attempts at producing music will probably result in something that sounds like a half‑hearted rendition of 'The Flight Of The Bumble‑Bee'. Changing the controlled MIDI instrument to other sounds, however, produces some very strange and effective noises. The Dimension Beam triggers individual notes a great deal faster than is possible when you're playing a keyboard or MIDI guitar, and some crazy effects can be generated as a result. Plug the unit into a sound source with long, resonating patches, and the cacophony of noise produced is worthy of inclusion in the next Star Wars movie; set the patch information to modulate a single analogue bass sound, and a didgeridoo‑style effect is produced as your hand moves in and out of the beam. The unit is ideal for live use, both musical and theatrical. A wave of the hand could, for example, trigger a musical effect or a change of lighting. For guitarists and other MIDI experimenters, Interactive Light supply a set of adhesive 'mirror' stickers. Sticking one around the neck of a guitar will allow the instrument to control the Dimension Beam, altering the effects settings of a processing rack, or triggering new delay settings.

A wave of the hand could trigger a musical effect or a change of lighting.

While it's not possible to generate System Exclusive information directly from the Dimension Beam, it is possible to map a controller number to a SysEx string using sequencing software, such as Notator Logic. Defining a new slider within the current environment, setting it to adjust the filter of a specific analogue keyboard directly from a specific controller number, allows the unit to sweep the filter using hand movements alone.


The proliferation of computer‑based soundcards, with built‑in banks of patches and sampling capabilities, has introduced a large number of people to the world of sequencing and recording. For those who lack playing skills, the Dimension Beam could be useful for developing musical ideas. Musicians who are currently developing sound effects and ambient music will find that the system offers a unique new approach to note‑generation, and is capable of turning the simplest of samples into fresh and exciting sounds. Its strongest market possibilities, however, would seem to lie in live performance, as a theatrical trigger, or an effects controller for the on‑stage musician. Having the capacity to alter sound settings depending on the position of your guitar or hand introduces a wealth of performance possibilities.

The Dimension Beam does have the odd limitation: for example, only one note event can be generated at the same time — chords are out of the question. There really is no substitute for the common keyboard in today's MIDI environment; however, as an alternative control source, the Dimension Beam is an invaluable tool. The ability to adjust parameter settings 'hands‑free' on stage, by waving a guitar or stepping into the beam, will no doubt be of major interest to performers everywhere.

Beam Shaping

In order to get the best out of the Dimension Beam, you need to carefully define the area of space that will receive your physical movements. The best way to imagine the shape of the field that the unit produces is to think of it as an apple, with skin and a core. The Dimension Beam focuses an apple‑shaped field of light directly above its sensors, and you can set a parameter value for both the skin and the core; changing their shape and size adjusts the MIDI values that are generated whenever movement occurs. Moving between the two then generates MIDI values that range between the skin value and the core value. Setting the co‑ordinates of the beam is done by holding your hand (or any other trigger) at the limit point and clicking an attached foot‑pedal, or adjusting the values directly from the unit's arrow keys.


  • Excellent alternative controller to add to an existing keyboard setup.
  • A wide range of continuous controller information can be sent.
  • Accurate and definable Beam field.
  • Sturdy design, capable of withstanding the knocks of touring and live use.


  • Cannot directly send System Exclusive data.
  • Monophonic control only.


Recommended for the musician tired of the limitations of a master keyboard, and for theatrical use or effects generation. Breathes new life into tired sounds and introduces a new and friendly way of recording MIDI‑based music.