A spotlight focuses on the solo performance artist as she lifts what appears to be a graceful black sword that's roughly the length of a violin bow and

A spotlight focuses on the solo performance artist as she lifts what appears to be a graceful black sword that's roughly the length of a violin bow and cradles it in front of her. She holds it with one hand, while with the other she begins to play music by tapping and sliding her fingers across its surface. Scales, arpeggios, and rapid-fire riffs burst forth as she changes from one instrumental sound to another, her hands never leaving the black blade. You catch a clearer glimpse of her unusual instrument and see the name "Kurzweil" emblazoned across it. As she launches into a piano solo, people around you ask no one in particular, "What is that thing?" With a smile you tell them, "It's a Kurzweil ExpressionMate."

When Moog, ARP, and Buchla synthesizers were first introduced in the 1960s, some of their keyboards were supplemented by a ribbon controller. By sliding a finger along the ribbon, you could glide between notes with slide-guitar fluidity. But the ribbon controller had largely disappeared until Kurzweil introduced the K2500, which featured a ribbon controller with much greater capabilities than its forebears. Now the company's ExpressionMate adds a ribbon controller to any MIDI synthesizer, along with a sophisticated MIDI processor and three independent arpeggiators that perform dozens of tricks never before possible.

FIRST GLANCEThe ExpressionMate comes with two parts and various accessories (such as cables and power supply). The first part is the ExpressionMate itself, a wedge-shaped black box with one small knob, a dozen switches, a dozen LEDs, and a 32-character LCD on the front panel (see Fig. 1). Various jacks grace the back panel (see Fig. 2). Cosmetically, it's a perfect match for any Kurzweil instrument and will look right at home sitting on your K2000 or PC88, but it works with any MIDI keyboard. If there's enough room, it can rest atop the synth's front panel. If that's not practical, you can mount the box on a microphone stand, using the included hardware.

The other part of the ExpressionMate is a metal-and-plastic ribbon controller 27.5 inches long by 1.5 inches wide (see Fig. 1). The ribbon is divided into thirds by white triangles that have been silk-screened onto it; other arrowheads indicate the half and quarter points within each third.

If you have the space, you can put the ribbon just above your keyboard by placing it on a foam strip or mounting it with Velcro (both of which are included). Otherwise, finding a convenient location for the ribbon can be a problem. On my Kawai K5000W, the space between the keyboard and the bottom row of buttons is not quite wide enough to accommodate the ExpressionMate's ribbon. I tried placing it on the overhang just below the front of the keyboard, but the ribbon's bulging ends prevented six keys from being fully depressed. I had to settle for letting its edge hang over the top of the keyboard just a bit. Sometimes I just set the ribbon in my lap as I play. If you have trouble making it fit, use your imagination-I've even heard of someone mounting the ribbon on a sanded-down guitar fretboard and hanging it from a guitar strap.

A cable resembling a telephone cord is permanently attached to one end of the ribbon controller. By default, you place the controller so that the cable is on the right-hand end, but if you change the Ribbon Direction parameter, you can flip the controller around so that the cable is on the left.

On the back panel are two sets of MIDI ports: Main In, Out, and Thru and Aux In and Out. These let you control two independent MIDI devices and input data from two independent MIDI sources. You also get two jacks for footswitches, one of which can be a continuous pedal. In addition, there's an input that accommodates a breath controller, which lets you use this device with any synthesizer. Two buttons on the front panel labeled SW1 and SW2 work just like footswitches for whichever functions they're assigned to.

OUTSIDE INThe ExpressionMate's greatest strength lies in its user programmability. It provides several physical controllers, including the ribbon, two panel switches, the breath-controller input, and the footswitch jacks. The panel switches and footswitches can be either momentary or toggle switches, depending on the current Setup (more on this shortly), and they can do anything from turning an arpeggio on and off to turning Sustain on and off.

The ExpressionMate provides 64 user-programmable Setups, which define what the various controllers do. Each Setup gives the ribbon and other controllers an entirely new identity. Only the first 31 Setups are preprogrammed; these are called ROM Setups, but they can be edited, erased, or replaced by the user.

Setups are manually selected by turning the front-panel data knob or pressing the - and + buttons below it. If enabled, MIDI Program Changes can also change Setups. Three Setup Lists are accessible with the < and > soft buttons. Press either button to go to the next Setup in the current List; press both buttons together to switch from one List to another. Setup Lists are useful for organizing Setups to make them quickly available during live performances.

You can assign the ribbon controller to control Pitch Bend, Volume, Effects Depth, Filter Swell, Panning, and just about anything that can be changed with a physical controller. When you slide a fingertip along the ribbon, the controller value changes in response. This response can be modified with one of a number of controller curves (see Fig. 3). The ribbon can even send Note On messages; although the ribbon is not Velocity sensitive, the Velocity can be determined by a user-assignable controller.

The ribbon can be configured as one long controller or divided into three sections. If the Split parameter is set to Single, the entire length of the ribbon controls a single parameter. If Split is set to Three Sections, different controllers are assigned to each section of the ribbon. For example, one section can play notes, another can control Velocity, and the third can control vibrato. If you have a MIDI-controlled lighting console, these three sections could control fades for three different scenes. You could also use them with a sequencer to trigger start and stop, punch in and out, and tempo.

When the ribbon is split into three sections, it's easy to accidentally cross from one section to another and get a result you didn't intend. It would be better if some sort of ridge divided the three sections. This would be especially helpful on dark stages, and I don't think it would interfere with using the ribbon in Single mode.

The ExpressionMate has two sets of "virtual" controllers, each of which sends three preset values when you select a Setup. These are typically used to send Program Changes, initial MIDI Volume, and so on before you begin playing. They can also send strings of System Exclusive messages. In addition, there are three MIDI Remap controllers, which change incoming MIDI data into other types of MIDI data. For example, you can use the mod wheel to change MIDI Volume, or you can use Aftertouch to control Pitch Bend. You can even make the pitch-bend wheel work in reverse. Virtually anything can be reassigned to anything else.

ARPEGGIATE THISBesides the ribbon, the most interesting feature of the ExpressionMate is its interactive arpeggiator section, which offers three 16-step arpeggiators that can receive and send on separate MIDI channels. They can even be cascaded so that one sends note data to another. All three share a common clock, either internal or external, but they can all play with different rhythmic values, meters, and loop lengths.

The ExpressionMate's arpeggiators are like others you might have used, but with a few new twists. In addition to the usual note orders (such as up and down, random, and the order in which notes are played on the keyboard), there are Random Walk, Fractal Walk, and Binary Walk, which are weighted variations on random order. Also, various latch modes determine how notes are triggered and whether they keep playing when you release the keys. For instance, turning on Glissando plays all the chromatic notes between the notes of the input chord. Besides playing all notes with an equal rhythmic value, the arpeggiator can play at preset rhythms from a bank of eight ROM Rhythms or 64 User Rhythms.

Several Shift parameters transpose the arpeggiated notes with each successive repetition. For example, if you set the Shift Amount to a whole step up, the pitches rise a whole step each time the cycle plays until it reaches the maximum transposition you indicate with the Shift Limit parameter. When the cycle reaches this limit, it can stop, start over, reverse direction, or transpose itself, depending on the Limit Option setting.

SET 'EM UPMost of the ROM Setups are intended for General MIDI instruments with the keyboard sending on channel 1. If you are controlling a non-GM instrument, you'll need to either turn off Program Change reception or edit the Setups. Kurzweil says the 31 ROM Setups are intended to show off the ExpressionMate's capabilities and encourage users to create their own Setups.

Some of the Setups are quite simple and straightforward. The best example is Setup 3, Big Strum. When you select it, the program on your GM synth changes to Jazz Guitar. When you play on the keyboard, nothing happens-but when you slide your finger on the ribbon controller, the notes you play on the keyboard are triggered by the ribbon, all with equal Velocity. As you ascend the ribbon, the pitches are transposed up by octaves. In other words, the notes you play on the keyboard become a scale you can play on the ribbon. If you press all 11 notes in a chromatic scale, you can play every note on the ribbon, with a range of up to four octaves. If you press only the white keys, the ribbon plays only white keys. If you play a chord, the ribbon plays only the notes in that chord, transposing up for each successive octave. Big Strum, or a close variation, might be the only Setup you'll ever need, because it lets you play the ExpressionMate as a musical instrument, with all notes triggered on the ribbon. A variation on Big Strum could turn the device into a unique percussion controller.

Unfortunately, predicting exactly which notes will be sounded by the ribbon is sometimes difficult, and when you play a note it's easy to accidentally trigger an adjacent note. Kurzweil recommends that you avoid trying to play in two different thirds of the ribbon at the same time when in Single mode. The company also suggests playing no more than two notes at a time to avoid unpredictable pitches. This is a significant limitation that prevents the ExpressionMate's use as a generally polyphonic controller.

Other Setups are more complex. Setup 23 is a cool example: it summons the General MIDI program Marimba, but this Setup is inexplicably called C2Drms 3/4B. Playing the note C2 triggers Arpeggio 1 at a preset Velocity. Playing any note between C1 and C2 triggers Arpeggio 2, which plays at the velocity with which you press the key. Pressing the SW2 button on the front panel stops Arpeggio 1, and pressing footswitch 2 turns off Arpeggio 2. Pressing SW1 stops both arpeggios. The ribbon's left-hand section controls reverb depth, the right section controls arpeggio tempo, and the middle plays a seven-note scale.

You must figure out most of this yourself, as the manual reveals only that playing C2 starts an arpeggio pattern and that the switches and pedals turn part of the pattern on and off. Most other ROM Setup descriptions are equally sketchy, so you'll have to explore them on your own to understand what they do.

One of the best ways to understand a Setup is by using a built-in utility program called MIDIScope, which works the same way as Kurzweil's MIDIScope for the Macintosh. MIDI data is shown on the LCD as it occurs; you can select whether you're monitoring data coming into or going out of any of the MIDI ports.

MANUAL LABORThe 132-page user guide is full of information, but it's not organized in a top-down fashion. For example, it tells you how to program the ExpressionMate, while never revealing why you might want to do so, or where it might lead. There are no tutorials, and many concepts are poorly explained; you pretty much have to read the whole thing just to grasp what's going on. An index is included, but the table of contents is a better place to find what you're looking for. In addition, the two "Quick Start" sections contain some erroneous and confusing information.

For example, the Arpeggiator "Quick Start" section begins: "1. Start with one of the Factory Setups. 2. Press the Arpeggiator button one or more times until the `Z1' light above the Arpeggiator button comes on." This works with only a handful of ROM Setups, but the manual doesn't tell you that. With most Setups, you can press the Arpeggiator button until the cows come home, and the Z1 light will never turn on. Even when I found a Setup that worked in this manner, following the subsequent instructions didn't give me the described results-very frustrating if you're just starting out. I finally figured out that I had to select one of the 31 initialized Setups (Fact Default) rather than a factory-programmed ROM Setup.

AN UNCOMMON EXPRESSIONThe Kurzweil ExpressionMate is a complex device-perhaps too complex for many musicians. Most of you will have to dig in and do some programming before it will perform the right tricks, but you'll be rewarded with incredible flexibility. Unless you're content just using Setup 3 to play notes on the ribbon, it won't satisfy your need for instant gratification. Once you step outside the realm of General MIDI, most of the ROM Setups are of limited use. I wish the unit included more factory-programmed Setups and better explanations of what they do.

How useful you find the ExpressionMate depends largely on your knowledge of MIDI. If you're not into programming MIDI devices, you might be disappointed. However, if programming custom Setups is your bag, you'll have hours of fun with the ExpressionMate. The depth of its programmability and its sheer number of parameters will teach you a lot about MIDI, even if you're fairly knowledgeable already. Once you've learned your way around the device and created some useful Setups, you'll have an alternate controller like no other.

Geary Yelton has composed and recorded music for DuPont, Hitachi, Delta Air Lines, and various other advertising clients. He recently relocated from Atlanta to Charlotte, North Carolina.