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Korg Kross 2

Workstation Keyboard
Published February 2018
By Gordon Reid

Korg Kross 2

The Kross 2 enjoys the twin benefits of Korg’s workstation pedigree and an attractive price tag.

Technology tends to follow a path from expensive to affordable. Computing power that would have required a government research grant a decade or two ago can now be obtained in your local supermarket, while the latest version of the flat-screen television that cost you more than £$2000 a few Christmases back is now on sale for £$399. The same is true in the world of keyboard workstations. Technologies first encountered in flagship instruments drift down until they appear in models that their manufacturers hope will be widely affordable. Take, for example, the Korg OASYS-88, which introduced the HD1 sample+synthesis engine to the world. This cost £5400$5000, but soon begat the M3-88, which was based on a cut-down version of HD1 called EDS and cost just £2600$2500. This in turn begat the M50-88 at £1500, followed by the Krome 88 (EDS-X) and then the Kross (EDS-i), which took the price of an 88-note Korg workstation to below £1000$1000.

This doesn’t mean that the Kross was an OASYS or that it provided the full HD1 engine for less than 20 percent of the original price, but much of the underlying synthesis had survived. Korg must therefore have been rather disappointed when the Kross attracted a degree of criticism, not because of its voicing, but in the way that it was implemented. On the other hand, the company must have agreed with at least some of the comments, because I now have in front of me the Kross 2, which appears to have addressed many of the questions raised about the original.

Programs

Like many of Korg’s earlier releases, the Kross 2 offers four primary modes of operation. The first is a Program (patch) mode, the second is a multi-timbral Combination mode, the third is Sequencer mode and, finally, there’s a Global mode that takes care of the internal drum kits and housekeeping duties.

Programs are based upon a pair of four-part, velocity-cross-faded, multi-sample oscillators that draw from approximately 112MB of ROM. This is considerably smaller than the 256MB ROM in the M50 and the 512MB in an expanded M3, let alone the massive 3.8GB inside the Krome, but there’s an as yet unused 128MB of RAM into which you’ll be able to load expansion libraries that, Korg say, “will be released following the Kross 2”, so we’ll have to wait to see what these offer. The outputs from each of these oscillators are passed to dual 12dB/oct multi-mode resonant filters that can be configured in series or in parallel or as a single 24dB/oct filter, and then to an audio amplifier. At every stage, a huge range of modulation options is provided, with contours, tracking generators, LFOs and Alternative Modulation Sources galore. Similarly, the Kross 2’s drum kits use up to four velocity-switched and cross-faded samples per instrument, and you can play these forward or backward with start offsets if desired. You can define the level and transposition of each instrument, sustain each after the trigger is released so that the sound is completed naturally, and there are additional parameters for filter cutoff and resonance, an AD contour that offsets the Program contouring, triggering modes, exclusive groups and more.

Nonetheless, the Kross 2 lacks some of the more sophisticated voicing features of the company’s more expensive workstations, including Wave Sequencing and Vector Synthesis. Also absent is KARMA, although I don’t think that many of Korg’s target users will miss this. Instead, there’s a sophisticated, programmable, polyphonic arpeggiator that’s far removed from the up/down/random devices of traditional synths. Sure, these simple patterns are available as presets, but there are a further 1280 rewritable pattern memories, and a wide range of parameters — octave range, resolution, gate length, steps per beat, velocity, flamming, swing and more — make it more of a mini-sequencer than an arpeggiator. You can even set things up so that a limited area on the keyboard will define and trigger the arpeggio, allowing you to play along with it.

Each Program also includes a drum track into which you can load one of 772 preset patterns, and a 64-step sequencer for creating your own patterns. Again, an extensive range of parameters is available and, on playback, you can synchronise the results with the other sections of the synth. Drum tracks also have access to the full effects structure of the Kross 2 with each instrument independently routable so, if you want your snares to suffer... sorry, I mean benefit from compression and gated reverb while your kicks are enhanced and your cymbals are flanged, that’s all possible.

The effects structure comprises up to five stereo Insert effects (the maximum number is determined by the ‘size’ of the effects selected) plus two stereo Master effects, although the M3’s and M50’s Total Effect slot has been lost as have 36 of their algorithms, the number of which in the Kross 2 is therefore reduced from 170 to 134. As usual, you can determine how the insert effects are chained, how their outputs are sent to the master effects, how the control busses provide the signals necessary for vocoding and the side-chained dynamics effects, and how they’re synchronised (or not) to the arpeggiator, the sequencer or MIDI Clock. The effects are, as always, based upon Korg’s REMS algorithms and, in my view, they’re often of sufficient quality to preclude the need for outboard gear.

Once you’ve completed your Program, you can decide whether to add it (or not) to your lists of favourites. You can also set up a Quick Layer or Quick Split with control over the volumes of the two component sounds and, in the case of the Split, their octave transpositions. If you save either of these, the results are stored as a Combi, but without the player having to understand how Combis are configured.

Combinations

Combi mode is a powerful tool that you can use as the basis of multi-timbral setups or for creating the complex sounds for which Korg’s workstations are rightly famed. As usual, a Combi is a composite of up to 16 Programs (here called Timbres) each with its own volume, pan, pitch, scale, crossfade-able keyboard and velocity zones, and MIDI settings. It also includes two arpeggiators and a drum track. You’ll find all manner of interesting ways to assign and trigger these, and I rather like the way that you can assign the arpeggiators to Timbres, and velocity-switch between them when applied to a single Timbre. You can also use the pad samples (see box) and the step sequencer within a Combi and, if selected, these occupy Timbre slots 15 and 16. So, while the Kross 2 isn’t in the same league as a fully fledged arranger keyboard, you can configure Combis that come pretty close to sounding like complete backing tracks. Unfortunately, it has lost the individual Timbre EQs found on the M3 and M50, although it retains a limited version of their Tone Adjust feature. Here, this allows you to affect each Timbre’s filter cutoff and resonance as well as its filter contour and its velocity sensitivity without altering the underlying Program. This means that, if you need a particular Timbre to be a bit brighter or to speak more quickly (or whatever), you can achieve this without affecting other Combis. For a long time, this was one of the holy grails of multi/combi modes and, although only eight parameters are offered, it’s very welcome.

In common with Korg’s previous workstations, you can’t import Programs into Combis complete with their individual effects. Instead, the same effects structure is available for Combis as for Programs, and you have to determine where each Timbre is inserted into the routing map. This means that you have to plan ahead, deciding which sounds will benefit from which effects, and find ways to make complex Combis sound as close as possible to what you had intended. It’s also worth noting that, while the Kross 2’s maximum polyphony has been increased to 120 voices (the maximum on the original was 80) this can only be achieved when using the simplest sound in Program mode or a single Timbre of the simplest sound in Program mode. If you increase the complexity and start layering Timbres, the polyphony will drop considerably and, as on all such instruments, it can drop all the way down to single figures in the most extreme cases.

The Sequencer

Although I would never use it in place of a DAW, the Kross 2’s 16-track sequencer could prove useful as a note pad and for replaying compositions. Its specification may not be up there with the most powerful devices of its type, but it’s no lightweight either, holding up to 128 songs comprising 16 instrument tracks and a tempo track, each of up to 999 measures, with an absolute ceiling of 210,000 MIDI events. For novices, it offers 16 template songs with preset instruments and their effects already allocated, or you can use Auto Song Setup to copy any of your Combis into it. Then, once you’ve recorded something, the usual range of editing functions are provided: inserting, copying, repeating, looping, moving and erasing measures, modifying notes, quantising, creating and modifying control data, and so on. You can also record SysEx as part of the performance, which provides myriad possibilities for automation.

As you would expect, each track in the sequencer can drive external sound sources as well as the Kross 2 and, again, you can allocate the Pad Sampler to track 15 to spin in audio such as guitar parts and vocals. Many years ago I used my Roland S770 in this way, recording guitar parts as extended samples and then triggering them from my sequencer. You’ll find that there’s much that you can achieve this way although, if you need true audio/MIDI integration within a keyboard, you should be looking toward the Kronos or one of its competitors. But perhaps my favourite sequencer function is something that we’ve already discussed. As in Combi mode, Tone Adjust allows you to tweak the Timbres inserted into the tracks without affecting other songs. Bravo!

The Kross 2’s front panel harks back to the late ’90s, but helps to keep the overall cost down.The Kross 2’s front panel harks back to the late ’90s, but helps to keep the overall cost down.

In Use

Setting up the Kross 2-88 is a doddle; at just 12kg or thereabouts, it weighs little more than half of the M50-88 that preceded it and which, a few years ago, I described as ‘remarkably light’. Happily, the weight reduction hasn’t been achieved by installing a cheap plastic keybed; while not in the same class as the best that the industry can offer, I found its weighted, graded-action, piano-style keys to be both playable and responsive. Instead, the weight saving has been achieved by replacing a lot of wood and metal with plastic. In the past, I was worried that larger synths and workstations with plastic chassis wouldn’t stand up to serious use, but the likes of the Roland Juno Stage and Korg’s own M50-73 have survived for the best part of a decade so I’m more relaxed about this than I was.

Given its heritage, you might expect the Kross 2 to boast a large, touch-sensitive screen and the type of user-interface found on Korg’s other workstations. It doesn’t. The screen harks back to the days of the T series in the early ’90s, with a huge number of pages containing densely packed parameters and values. Furthermore, its control panel is rather sparse and, rather than offer a large number of physical controls, it provides a 6 x 3 matrix in its new and cunningly named Realtime Controls section. In short, you select the thing that you want to modify, and then use the switch and two knobs to modify a subset of the parameters that affect it. It’s very limited when compared with a ‘knob per function’ design, but given the number of parameters available and the impracticality of a surface the size of an aircraft carrier, it’s an efficient way to place some of the most important parameters beneath your fingers. On the 88-note version, this also leaves room for a compartment in which you can store small cables, SD cards, and so on. Since the insides of many modern synths are largely empty space, that’s a sensible idea. Moving on, you can assign a wide range of functions to the pedals, wheels and performance switches, and you can use the pads to control the step sequencer, to trigger samples and to select favourites, so you have a reasonable degree of real-time control available, even without the more expensive facilities of, um, more expensive instruments.

Nonetheless, its sonic character is much as you might expect. The number of underlying samples in EDS-i has been significantly reduced from the 1077 multi-samples and 1609 drum samples in the EDS workstations to just 496 multi-samples and 1014 drum samples, but many of its sounds would still grace any gig or recording. From top-quality pads and orchestral sounds, to electro-mechanical pianos, to superb organs, to percussion and special effects, I found that many of the factory Programs were immediately usable and, if one wasn’t quite right, a little tweaking could work wonders. This was particularly apparent when playing some of the e-pianos, in which the factory Programs exhibit abrupt break points between the rounder timbres when played lightly and the brighter timbres when played hard. For some reason (perhaps to avoid unwanted phasing or chorusing) Korg’s programmers omitted to crossfade the underlying samples, but I found that doing so improved matters considerably. Sure, there are some sounds (most noticeably the grand pianos) for which the Kross 2 doesn’t have quite the depth of Roland’s SuperNatural synths or Kurzweil’s VAST workstations (or, for that matter, Korg’s own Krome and Kronos) but we have to consider this in the context of its price.

Inevitably, the Kross 2 suffers from a number of other shortcomings. For example, there’s no XLR microphone input. I own at least a dozen microphones, and not one of them has an unbalanced quarter-inch jack plug on the end of its cable. Then there’s the choice of the storage medium; in my view, modern synths and workstations should use USB memory sticks with a recessed socket so that they can be left in situ during transportation. Then there’s the biggie... It’s a great shame that its keyboard cannot generate aftertouch. I realise that this was omitted to provide differentiation from Korg’s more expensive instruments but this, together with its external PSU, precludes it from my live keyboard rig. If I’m using both hands to play a piano/orchestra Combi and I want to swell the strings, I want aftertouch. Likewise, if I’m using one hand to play a monosynth lead and the other to play the organ accompaniment, and I have my feet poised above a bass synth and various swell pedals, I need aftertouch to control the Leslie effect. Nonetheless, aftertouch is supported over MIDI and can be programmed as a controller within the sequencer, so the synth engine supports it even if the mechanical stuff doesn’t.

Finally, despite the blurb promising that the “dedicated Kross 2 Editor and Plug-In Editor are also provided”, there was no trace of these at the time of writing. I liked the M50’s editor/librarian because it made programming quicker and easier. Given the Kross 2’s small display and 1990s-style operating system, an editor will be of even greater benefit here, and the plug-in version will make it possible to edit and automate the Kross 2 from within your DAW of choice. Hopefully, both will have arrived by the time that you read this.

Conclusions

The Kross 2 isn’t expensive and it isn’t state-of-the-art, but you shouldn’t discount it for those reasons. I hadn’t expected to be impressed, but it’s a far better instrument than I had anticipated, and a significant improvement over the original Kross, both in terms of sounds and usability. It’s lighter, has improved battery life, has more memories with double the number of Favourites, offers improved controls, and adds the expansion memory, the pad sampler, recording, and audio/MIDI over USB. Sure, Korg’s claim that the Kross 2 is “the mobile synthesizer workstation that does everything” is ridiculous (the same company makes workstations that do much more), but it’s an attractive option for players who don’t require the power of the Kronos and its ilk, opening a door into the world of synthesizer workstations at a price that many will find attractive.  

The Audio Recorder & Pad Sampler

The audio recorder allows you to record up to 200 stereo ‘Songs’ in 16-bit/48kHz format, each up to three hours long. Of course, no SD card will hold 600 hours of uncompressed audio, but the synth isn’t superimposing any limitations here. Songs can be recorded from external audio, imported from WAV files, or recorded from live performances and sequencer playback from the Kross 2 itself. Once recorded, you can overdub if required and then assign up to 128 of the resulting songs to the pads (eight banks of 16 samples) so that you can spin things such as extended vocals and acoustic instruments into your performances and compositions. Alternatively, you can replay complete backing tracks and add a bit of live performance to these — not that I would ever condone this, of course.

The Pad Sampler is a variation on the theme. In this case, you can record up to 128 stereo samples of up to 14 seconds duration, or load the first 14 seconds of suitable WAV files. Editing then comprises specifying the start, loop and end points of each sample, as well as truncating and normalising them if required. You can then replay up to four samples simultaneously, although not through the effects section, which is a shame. Intriguingly, you can convert a bank of Pad Samples to a Program, but you can’t map them chromatically across the keyboard, merely place them under the 16 keys C2 to D#3. It’s far from the “superb sampling functionality” promised by the blurb, but, as elsewhere, we have to evaluate this in the context of the price.

The Rear Panel

Korg Kross 2I wasn’t surprised to find that the rear panel is a bit sparse. Most noticeable are the loss of multiple audio outputs and the provision of just a single L/R stereo pair for all audio, together with a headphones output that echoes these. (On the 88-note version, the latter is found on the front of the instrument, which is good.) Next to these, you’ll find mutually exclusive 3.5mm line-level (stereo) audio and quarter-inch (mono) unbalanced microphone inputs. On the other side, there’s the slot for the SD/SDHC card that’s necessary to record and replay the resulting recordings and samples but which can also be used for standard data storage functions. Audio and MIDI can be input and output over the USB interface but, if you prefer to use traditional 5-pin DIN connections, MIDI In and Out are provided, although there’s no Thru. Three controller inputs are provided: one for a damper/half-damper pedal, one for an assignable expression pedal and the third for a pedal switch.

The final hole in the back is for a 9V DC external power supply and, although there’s a cord hook, I can’t understand why manufacturers persist with barrel sockets when various forms of locking connectors are available. You can also power the Kross 2 using six AA batteries, which should last for six or seven hours of normal use and might avoid embarrassment if the PSU becomes detached.

Finally we come to the illuminated Korg logo, which I view as pointless. I can’t see why you would want it in the studio and, on stage, your lighting engineer will cover it with gaffer tape. Fortunately, you can switch it off.

Abridged Specification

  • Keyboard: 88-note velocity-sensitive graded hammer action.
  • Maximum polyphony: 120 voices.
  • Oscillators per voice: Two.
  • Oscillator structure: Four velocity zones offering switching, crossfading and layering.
  • Filters per voice: Two multi-mode filters (LP, HP, BP, BR).
  • Filter routing: Single, in series, in parallel, or combined into one 24dB/oct filter.
  • Modulation per voice: Two contour generators, two LFOs, two AMS mixers, two tracking generators.
  • Modulation per sound: Pitch contour generator, common LFO, two tracking generators.
  • Combination mode: 16 Timbres with individual Tone Adjust.
  • Drum kits: Samples with four-way velocity switches.
  • Memories: 1280 Programs, 896 Combinations, 58 Drum Kits.
  • GM2 memories: 256 preset Programs, nine Drum Programs.
  • Favourites: 128 (eight banks of 16).
  • Effects structure: Five Insert effects plus two Master effects.
  • Effects types: 134.
  • Polyphonic arpeggiator: 1280 patterns, 12-note polyphonic, of up to 64 steps.
  • No. of arpeggiators: One in Program mode; two in each of Combination and Sequencer modes.
  • Drum Tracks: 772 patterns.
  • Step sequencer: 12 notes plus accent, up to 64 steps; one for every Program, Combi and Song.
  • Sequencer: 16 tracks of up to 999 measures; up to 128 songs; max 210,000 MIDI events.
  • Pad sampler: 16 pads × eight banks — up to 14s of audio per pad.
  • Audio Recorder: Up to three hours continuous 48kHz/16-bit recording per song; up to 200 songs.
  • Display: 240 × 64 backlit LCD.
  • Power: 9V DC or six AA batteries.
  • Dimensions: 1448 × 383 × 136 mm.
  • Weight: 12.3kg.
Published February 2018