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Korg Electribe EMX1

Korg Electribe EMX1Photo: Mike Cameron

This new member of the Korg tribe offers synthesis, sequencing, drum programming, tons of real-time control — and genuine valves to light up your studio and your sound.

Korg's Electribe family of dance-biased synth and sampling sequencers has recently grown to six, after (amazingly) nearly five years since its inception. During that time, the range, which kicked off with the EA1 and the ER1 in 1999, has developed a significant niche for itself in the market. Given that much current electronic music exploration has become centred on computers and software, it's heartening to see that there are still plenty of people who value the hardware experience.

This latest Electribe product is a development of the EM1 (released almost exactly two years ago), a combination of eight-part drum machine and two-part synth/sequencer. The EMX1 grows a number of extras: one more drum voice, three more sequenced synths, more knobs and buttons, Smartmedia card storage, a much more informative display, an extra pair of outputs, an audio input, and — most unusually! — a stereo pair of Russian-made Electro-Harmonix 12AX7 valves.

Look & Feel

Solid. That's the first word that comes to mind when encountering the EMX1, with its all-metal casing. If there were a decent word to describe knobbiness, that also would be appropriate, due to the large number of them — 20, plus a slider and a ribbon controller — that adorn the front panel. And let's not forget the buttons, since there are no less than 68 on board. There is no word, decent or otherwise, to express the surprise at seeing a pair of valves behind that front-panel window, but these also loom large in one's first impression of Korg's new all-in-one composition tool (see the box on the next page for more on the valves).

Korg have introduced a new acronym for the EMX1's sound generation system: Multi Modelling Technology (MMT). Essentially, this means physical modelling, though a selection of sampled waveforms is included to take care of the drum voices and a couple of the synth-oscillator options. Sonically, the EMX1 inherits much from Korg products past, and dedicated Korg users will recognise sonic elements from instruments such as the MS2000 and previous Electribes.

In common with other Electribes, each drum and synth voice is organised as a Part, an indivisible pairing of a voice generator and one track of sequencing played by the Pattern-based sequencer. Step sequencing is favoured, especially for drums, but real-time recording with the EMX1 is straightforward. Voice editing is very much a part of the writing process, since sounds and sequencing are so closely linked. Indeed, there are no separate voice memories: sounds are tailored for each Part during the composition process.

The synth/sequencer team is joined by three effects processors, a nifty — and new — real-time arpeggiator, the ability to process external audio through the EMX's synthesis facilities and effects, and 'Motion Sequencing', the real-time recording of front-panel control tweaks, as featured on many other Korg products.

The striking metallic-blue front panel is quite logically divided. You can easily pick out the synth section, effects, Part select and keyboard button area, and the row of 16 'keyboard' buttons, which also doubles up for a range of edit options, and mimics the black and white keys of a musical keyboard. The standard sequencer transport controls appear to lack fast forward and rewind options, but in fact they're located above the keyboard buttons, doubling as left/right select keys.

The EMX1 has a full MIDI spec, accessed via MIDI In, Out and Thru sockets, and audio is also bi-directional, with two main and two assignable individual audio outs, plus an audio input. Only mono audio (at mic or line level) can be accommodated, but this option still offers interesting possibilities for integrating external sounds into an EMX1 performance. The machine can even be sync'ed to audio via this input (of course, it can be sync'ed to MIDI too), which should make it even more useful in a live or club environment.

Staying with the rear-panel sockets for the moment, power is supplied via an unwieldy external PSU. Looking back at earlier reviews of Electribe products in SOS, I spot that I'm not the first to notice the lack of footswitch sockets. Even just some way to step through Patterns would have been handy.

The back panel may look unfinished, but that's just because all the legending is to be found at the top of the front panel. It may look as though there are several inputs and outputs; in fact there's a headphone socket, a main stereo output pair, two additional outputs, and a mono audio input (with associated mic/line level-adjustment switch to the left). The prominent grille in the centre provides ventilation for the valves.The back panel may look unfinished, but that's just because all the legending is to be found at the top of the front panel. It may look as though there are several inputs and outputs; in fact there's a headphone socket, a main stereo output pair, two additional outputs, and a mono audio input (with associated mic/line level-adjustment switch to the left). The prominent grille in the centre provides ventilation for the valves.Photo: Mike Cameron

Oscillator Types

It would take too much space here to list every oscillator option, but it's worth giving you a taste of what Korg provide. Classic two-oscillator analogue synth models feature heavily, with a choice of Sawtooth, Pulse/Square, Triangle and Sine waves offered by many oscillator 'types'. A noise-generator option is provided in some models.

Departures from the standard two-oscillator mode include the four-strong Chord Oscillator and the fat and detuned six-way Unison Oscillator. Classic synth techniques are also modelled, so you can select a Ring Modulator for clangorous, metallic 'sum-and-difference' sounds and an Oscillator Sync option, which is great for soaring lead sounds. Cross Modulation creates complex waveforms by modulating Osc 1 with the output of Osc 2, while the Variable Phase Modulation Oscillator is capable of creating further metallic sounds by modulating the phase of one oscillator with another. More complex waveforms are generated by the Waveshaper option, and simple Additive synthesis can also be dabbled with, via a three-oscillator stack. With the Formant Oscillator, human-sounding vowel-like sounds can be produced. For sounds that can't be easily modelled with 'analogue' oscillators, two oscillator types use samples — pianos, basses, wind instruments and so on.

Synth Parts

I'll now try to tweeze apart the sound generation and sequencing sides of the EMX1. Each of the five synth Parts is identical, featuring an oscillator, filter, modulation, a basic Envelope Generator (or EG), plus level, pan and effect-send controls. The oscillator is a bit tricky to describe, since what it does depends on the setting you select. There are 16 oscillator types, chosen by the large knob in the synth edit section, but each type has a sub-set of waveform variations, resulting in an effective total of 258 oscillator types. Most of the oscillator types are modelled and range from a simple two-oscillator model to multi-oscillator detuned unison models, plus creative paydirt such as formant, comb-filter and additive models (see the box below for more on the oscillator types). Two of the options actually employ one of 76 PCM samples, in combination with comb filtering and waveshaping, and the final option applies a comb filter to the audio input (which can also be filtered, modulated and effected as if it were an ordinary oscillator).

Once the oscillator type has been chosen, two 'Osc Edit' knobs alter a pair of important parameters; which ones depends on the oscillator type. For example, with the basic 'Waveform' option, which assigns the same waveform (sawtooth, pulse, triangle or sine) to both oscillators, these knobs alter waveshape and Oscillator 2 pitch; if the Chord Oscillator (which generates a four-voice chord from a single note) is in use, one knob chooses the chord type, while the other alters its voicing.

Whatever oscillator type you choose, it can be processed by the newly designed and pretty chunky filter. This offers a choice of low-pass, high-pass, band-pass and 'band-pass+' characteristics. The last of these basically mixes the band-pass filter output with some of the original waveform. Cutoff frequency and resonance controls are augmented by a Drive (overdrive) parameter, and in combination these three parameters allow the filter to go from quite subtle to absolutely screaming and grungy. The Drive control certainly helps give EMX1 sounds an upfront feel, and the filter has a good sound already; the resonance can really get out of control (a good thing in my book!).

There isn't a filter envelope generator as such. In fact, a rudimentary envelope for the filter is taken from the setting of the amplitude envelope, which is itself very basic. However, an 'EG Intensity' knob allows the filter envelope effect to be made more or less pronounced, and this works surprisingly well.

The modulation section offers a tempo-sync'able LFO, with a choice of standard waveforms including sawtooth, square, triangle and random. Modulation depth is governed by a dedicated knob, and there are six possible modulation destinations (only one can be used at a time per Part): pitch, oscillator edit knobs 1 and 2, filter cutoff frequency, amplitude and pan. I have no idea why only three of the destinations are highlighted on the panel, though!

Finally in this area, the so-called Part Common parameters offer control over glide, pan position, level, EG controls and effect sends. It has to be said that some compromises are revealed in this section, although none is fatal in the context of an instrument that strives to be immediate to use. First of all, the EG, which as mentioned above, is very simple. A button labelled Amp EG selects between a straight gate on/gate off envelope and a decay-based envelope. The decay is defined by a single knob — the same one that governs filter EG decay time. A little more control would have been welcome, if only to modify the attack of a sound. Still, considering this limitation, sounds can be contoured quite well.

Less forgiveable is the way in which the level control doubles as an effect-send control, especially since this arrangement means that it's not possible to set level and effect send amount separately; if there's too much effect, turning the knob down also turns the Part's overall level down. This is pretty annoying. It's a bit sad, too, that signal from each Part can only be 'sent' to one effect. Looked at in another way, this may be Korg's compromise solution to the issue of whether to include insert or send effects: those on the EMX1 function halfway between the two types. All this said, if the EMX1 is accessed over MIDI, Continuous Controllers and NRPNs address level and effect send controls separately.

Better By Tube?

Korg Electribe EMX1Photo: Mike CameronThere's not a lot to say about the valves, though they are perhaps the most visually striking aspect of the EMX1. Their effect is added via a single knob, and this can range from a subtle fuzziness to quite outrageous distortion. And the more you add valve effect, the louder the output of the EMX1 becomes, so be warned that your monitoring system may have to be adjusted. This is a welcome effect, though, and it's nice to be adding real analogue warmth rather than another digital simulation.

One small issue, though: the valves have pride of place behind an oval glass window on the front panel, allowing you to bask in their warm glow — strangely, though, it's not the warm glow of the valves themselves, but of two yellow LEDs soldered to the circuit board! This is reminiscent of the moulded fake tweeters and bolts on '80s-vintage Amstrad 'hi-fi' equipment! The window does get physically warm, but not hot: grilles on the rear panel and underside allow air to circulate.

Korg have sat on the transatlantic fence with regard to whether the glass bottles are valves or tubes: the knob is labelled 'Tube Gain', but the window is labelled 'Valve Force', and the technology is referred to, in the manual, as the Valve Force vacuum tube circuit.

Drum Parts & Effects

Drum voices are firmly sample-based. One of 207 PCM waveforms can be selected as an 'oscillator', to which can be applied synth-style Part parameters such as tuning, EG, level, pan, effect send and modulation parameters. There's no filtering, unfortunately, and the modulation destinations are restricted to pitch and pan. The sample set includes a good variety of drum sounds, real, contemporary or classic electronic. If you feel the need for something a bit more creative, the synth Parts can be coaxed into producing quite interesting synth drum sounds, although this obviously eats into your synth-voice quota.

The EMX1's effects complement is reassuringly comprehensive. Three processors, each offering a choice of 16 effects, can be used in parallel, or in one of a variety of chains, including one that links all three. Editability has been kept to a minimum, with just two parameters per effect.

There are no hidden extras, and I did miss having a choice of reverbs. The single algorithm provided is bright and useable for most purposes, if a little ringy when fed by percussion or heavily filtered bleepy sounds, but how much trouble would it have been to provide a couple of choices? The remaining effects are just fine, comprising tempo-sync'ed delay, ring mod, mod delay, chorus/flanger, phaser, talking modulation, pitch-shift (this is interesting on external audio, though not always in a good way!), distortion, decimator, EQ, a low-pass filter, a high-pass filter and a 'grain-shifter'. All are equally serviceable, though it's worth remarking on the talking modulation, a formant-like effect I enjoyed tremendously, and the potentially interesting but unpredictable grain-shifter.

Previous Electribe Reviews In SOS

  • Electribe EA1 Analogue Modelling Synthesizer & ER1 Rhythm Synthesizer: July 1999.
  • Electribe S Rhythm Production Sampler: August 2000.
  • EM1 Electribe Music Production Station: September 2001.

Sequencing: Patterns

The sequencing side of the EMX1 can be easily summarised. Each pattern can be up to eight bars long, and bars can consist of 16 16th-note steps (a standard 4/4 bar), 16 32nd-note steps, 12 eighth-note triplets or 12 16th-note triplets. The triplet options let you write triplet-feel 4/4 or ordinary 3/4 bars, and irregular time signatures can be accommodated (somewhat) by the 'Last Step' command, whereby you choose which step, of the maximum of 16, will be the last in a Pattern bar. Such a choice may throw the built-in metronome into confusion, but you could create one of your own if needed, by temporarily using a drum Part. A triplet-like feel can also be added courtesy of a variable 'Swing' parameter.

It's possible to record everything in real or step time, with no difference between modes. You simply jump in and record however you like. For example, to record a drum part in real time, hit the Drum Part buttons. To fine-tune the part or record in step time, select a drum Part and use the keyboard buttons (whose function then changes to define steps at the desired resolution — a step where there's a hit lights up) to input the hits you'd like to hear.

It's just as easy to record real- or step-time synth parts. For real-time recording, you go into record and play the notes via the button keyboard (it's transposable over a range of eight octaves). For step-time work, the keyboard buttons function in a similar way as for the Drum Parts. Gate time can be altered in the display, though there are rest and tie options amongst the front-panel controls, so note length can be manipulated somewhat in step mode.

Parts can be recorded from an attached MIDI keyboard, too, and although the EMX1 will respond to velocity and pitch-bend, this data is not recorded as part of a Pattern. Dynamics are, rather sadly, limited to a user-defineable 'Accent' track for the drum Parts and one for the Synth Parts. Potentially, this is useful, but as with drum machines from the dawn of '80s synth pop, an accent on a step affects all events playing on that step, so all drum hits/synth Part notes playing on an accent will be affected. A Part can be set to not respond to the Accent track, though, which helps.

Once a Pattern is recorded, there are various ways to edit it, and most editing can be done while a Pattern is playing. The Shift key comes into focus now, as it and one of several clearly labelled keyboard buttons are pressed to access the Pattern Edit functions (the manual will be of use here, since it's not always obvious how routines such as Copy Sound and Copy Part work). As suggested earlier, note events can be edited, and chunks of sequence data can be moved forward or backward, repeated and transposed. A couple of randomise options let the EMX1 rearrange your performance to create potentially interesting new material.

Beyond recording notes, it's also possible to record 'Motion Sequences' as a sort of overdub to the main pattern. Up to 24 knob or button-tweak performances, to add dynamic parameter changes throughout the sequence, can be thus recorded per Pattern. Usefully, Motion Sequences can themselves be edited, on a step-by-step basis. This is not as counter-intuitive as it may seem, since there are two Motion Sequence playback options. The Trigger Hold option plays back just the 16 discrete values recorded on the 16 steps, whilst choosing the Smooth option causes the values between the discrete steps to change, more accurately replicating your performance. The first is ideal for changing button states or, for example, to automate Chord Name changes for the Chord Synth Oscillator type. Smooth would be the choice for automated filter resonance tweaks and the like. The Effects section has its own Motion Sequence facility, restricted to the two 'FX Edit' knobs for each of the three effects, though this runs only in 'Smooth' mode.

As shipped, many of the EMX1's 256 Pattern locations are filled with factory Patterns; these can be easily overwritten (and restored later if required).

Ups & Downs — The Arpeggiator

Korg Electribe EMX1Photo: Mike CameronThe EMX1's arpeggiator is rather novel, accessed via a ribbon controller (which initiates the arpeggiation and changes between staccato and legato effects) and a slider (which steps through a user-selectable scale type over a range of two octaves). More standard arps can be set by pressing and holding the keyboard buttons, the result being transposed in response to changes in the scale type. Types range from chromatic to a variety of modal scales, plus simple intervals of a fourth, fifth and octave. The ribbon and slider function can be swapped, and the playback feel changes if you select a different Pattern 'beat' — 16th, 32nd, eighth triplet or 16th triplet.

This is a fairly simple device, then — but such simplicity is not apparent in the results you can obtain. It can be a truly amazing effect, and can be recorded into a Pattern or a Song. Add tempo-sync'ed delays, and even the simplest Pattern grows 'feel'.

Sequencing: Songs

Once you've created some Patterns, they can be chained in one of 64 Song locations. A maximum of 256 Pattern steps per Song is available. But the fun doesn't end here, as the Motion Sequencer can also be used in Song mode, so real-time knob tweaks, mutes and solos can be recorded in addition to any in the original Pattern(s). And then it's also possible to record a real-time note-based or arpeggiator-driven performance as a sort of MIDI overdub to a Song; leave a synth Part free if you'd like to try this at home. There is room for 20,000 of these overdubbed 'events'. Sections of Song can also be transposed — transposition affects the synth Parts only, obviously — and Pattern steps can be deleted or inserted.

For a live performance, you might find it useful if the EMX1 could play back successive songs automatically. Happily, it can! A 'Next Song' parameter lets you set which Song will be played when the current Song is finished. You can thus customise an EMX1 playlist.

Other Neat Stuff

Beyond the straightforward Pattern-based sequencing faciities offered by the EMX1, it can be used in other ways, too. For example, it makes a fine sound module. There are no hidden facilities (apart from being able to adjust Part level and effect send separately), but practically every control for every Part can be addressed by its own MIDI Controller or NRPN. All the synth and effects edit knobs also transmit MIDI data — and different MIDI data for each Part's collection of knobs — which makes the box more versatile in a larger MIDI studio. And of course, should you require it, the EMX1 can trigger sounds on other sound sources (you can even send out the output from the arpeggiator!). Live performance types will appreciate the Pattern Set feature: a Pattern is assigned to each of the 16 keyboard buttons, which can then be used to select Patterns on the fly.

I've already mentioned that a signal coming in at the audio input may be treated by the EMX's synthesis path, but alternatively it can be simply routed through the EMX1 for synchronised playback alongside an onboard performance. There's yet another aspect to this, since the EMX1 can perform 'beat detection', taking peaks in rhythmic audio as a timing reference. With suitable steady-tempo material, the resulting sync is quite reliable and useable. Shame that the audio input is mono.

Get Smart!

Smartmedia cards aren't exactly dirt cheap yet, but this is still a robust and convenient way to back up your work, so it's good to see the card slot on the EMX1. If you gig with the EMX1, buy at least one card. If it saves you from a crash at one gig, the investment is repaid. Not that the Electribe is flaky — during the review period, it wasn't — but there's no knowing what might happen in a live situation.

There is a cheaper way of backing up your work, via MIDI dump, if you have a computer or data-filer device capable of accepting the data.

Summing Up

Korg EMX1 top panel.Photo: Mike CameronIn conclusion, I found the EMX1 a doddle to use. It's hard to say for certain how any newcomer will take to such a product, but a hunt around various internet forums seems to indicate that newbies find the Electribe family rather more approachable than similar products from other manufacturers. Certainly, instant gratification (and a collection of great synth sounds to copy) is available amongst the numerous and expertly programmed factory Patterns. Most contemporary idioms are represented. If you have a little, or a lot of, experience you'll be able to dive in right away, since all the clearly labelled buttons work in exactly the way you'd expect them to. I went from box-opening to Pattern creation and Song chaining, with mutes, arpeggiations, and Motion Sequencing, in less than half an hour, and still wasn't bored a few hours later.

Many real-time tricks can be achieved, but some involve manual dexterity that might be beyond some. For example, you can set up a custom arpeggiator pattern, have it play without touching the keyboard (the last note or notes pressed make up the arpeggiator pattern) and transpose it on the fly using the Solo/Transpose button. However, this involves holding the Solo/Transpose button down with one finger on your hand, while using a thumb or other finger to make the transposition on the keyboard, if you need the other hand to alter the arpeggiator controls. There is no way to make the arpeggiator 'hold' an arpeggiation.

I found it useful to be recording the EMX1's output a lot of the time I was experimenting: the combination of real-time arpeggiator and tempo-based effects and modulation meant I was discovering sounds and textures I really wanted to retain. There's great potential for sampler fodder here.

The lack of voice memories might be thought of as a negative point, but you won't find it in my list of 'cons'. I like it this way: you're forced to create new sounds for every Pattern, and in any case, drum and synth settings can be easily copied from one Part and/or Pattern to another. The EMX1's synthesis facilities occasionally feel a little 'boiled down', but in providing the user with the bare essentials, Korg have produced an instrument that spends very little time getting in the way of creativity.

As much as I've personally moved more to software synths and virtual studios for my own work, for reasons of both space and mobility, I can't help being tempted by devices such as this. I could replicate most of the effects and music I produced using the EMX1 within, say, Reason, but many of them wouldn't have occurred to me in the first place or arisen from within that environment. As inspiring and powerful as software is, there will always be music and ideas that can only be generated by playing with real hardware, and this box is one of the good ones.


  • Easy to use.
  • Great sound.
  • Novel approach to arpeggiation.
  • Valves really do add presence and depth to the sound.
  • Audio input.


  • Audio input mono only.
  • Very basic envelope generators.
  • Compromised effects routing.


The EMX1 sounds great, is easy to use, and can produce exciting and satisfying results. With instruments this good, hardware continues to have a bright future in electronic music production.


£579 including VAT.

Korg UK Brochure Line +44 (0)1908 857130.