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Korg Kronos

Keyboard Workstation By Gordon Reid
Published May 2011

Korg really know what they're doing when it comes to workstations, and their new one has been eagerly anticipated. Meet the Kronos in our world exclusive review...

The 73‑note version of the Kronos employs the fully‑weighted RH3 keyboard found on Korg's SV1. The 73‑note version of the Kronos employs the fully‑weighted RH3 keyboard found on Korg's SV1.

When Korg released the M3, I wondered whether this might be the company's equivalent to the CS80 — a great synth built on similar technology to a rare and expensive predecessor, but refined and made affordable. However, while its EDS (Enhanced Definition Synthesis) sound generator was based upon the core HD1 (High Definition) synthesizer engine in the flagship OASYS, it offered a smaller ROM, less processing power, less sample RAM, fewer effects slots, and lower polyphony. What's more, it didn't support the OASYS's EXis (expansion instruments), so six of the OASYS sound generators were missing. I concluded that the M3 was more a step up from Korg's Triton than a step down from their OASYS, and was not a replacement for the company's previous flagship.

But now there's the Kronos. Announced at the NAMM show in January and, at the time of writing, still a few weeks away from distribution, its specification looks much like a revised OASYS. And, although its sombre styling is more reminiscent of an M1 or a Wavestation, its control panel also looks suspiciously like that of an OASYS. So is this the instrument to take Korg forward into the next decade?

The Core Of The Kronos

Korg have written a dedicated Expansion Instrument (EXi) to make best use of their two new families of grand piano samples. Despite being very simple to use, the results can be outstanding.Korg have written a dedicated Expansion Instrument (EXi) to make best use of their two new families of grand piano samples. Despite being very simple to use, the results can be outstanding.

Let's be clear from the start: the core of the Kronos is the core of the OASYS, and nowhere is this more apparent than in its implementation of HD1. In the OASYS, HD1 drew upon 1505 multisamples and 1388 drum samples, plus two expansion libraries: EXs1, which included 229 multisamples and 1483 drum samples, and EXs2, which offered 10 concert grand piano multisamples, all of which resided on its 40GB internal hard drive. Later, an optional upgrade (EXs3) added a further 700MB of brass and woodwind samples, although this could only be used if you expanded the OASYS to its maximum 2GB of RAM.

In the Kronos, HD1 is retained in full on its 30GB solid state drive (SSD), with a core of 1505 multisamples and 1388 drum samples, plus three expansion libraries, EXs1, EXs2 and EXs3, that comprise... well, you get the picture. But in addition to this, it also includes, as standard, no fewer than six further expansion libraries, EXs4 to EXs9, comprising Vintage Keyboards, a second ROM expansion, two new piano libraries, and two new drum libraries.

It's not possible to review HD1 in a 'select some waveforms, mix them and then send the results to the filter and amplifier' fashion, because each oscillator can be based upon PCMs, samples or wave sequences, each can use up to eight velocity-crossfaded sources (the OASYS only offered four) and the outputs from these can be modified and controlled by a vast array of multi‑mode filters, LFOs and envelope generators, multiple Alternate Modulation Sources, AMS Mixers, and more. Then there's the Vector Synthesis that lies at the heart of every Program, allowing manual and enveloped control over dozens of voicing parameters, and Drum Tracks (see below) that are integrated within each, to say nothing of the KARMA algorithmic composition technology, which can be used for anything from building simple arpeggios to complete tracks. It can sound fantastic and, if I'm honest, I don't think that anyone will ever exhaust the possibilities of HD1, especially with the new EXs libraries on board.

The EXs6 and EXs7 libraries provide the samples for two new pianos, and these are so important to Korg that the company have developed a new engine to make optimal use of them. SGX1, which is one of eight expansion instruments in the Kronos, offers eight velocity layers per note, with the natural piano noises — damper thunk, case noises and so on — separated out for independent control. What's more, there's no sample looping. No longer does a realistic attack turn into a featureless loop when a key is held, and each note now decays smoothly for as long as 30 seconds from its beginning to its end.

Each of the two piano libraries is sampled from a single instrument; EXs6 is a Steinway Model D, while EXs7 is a Yamaha C7. The sampling is first‑rate for both, and the noise layers add considerably to the illusion, both for the player and the listener. However, rather than offer just two pianos based upon these, the two sample families have been moulded into 32 preset instruments that you can further customise using a dozen or so parameters, and there's also an option to choose one of two soundfields: that which you would hear facing the keyboard as the player, and that which you would hear in the audience with the piano side‑on. I prefer the latter, which has excellent ambience and is more appropriate to anybody but the player anyway.

Physically Modelled Synths

Unlike most workstation sequencers, the Kronos's Track Data Map can show the status of all 16 MIDI tracks, all 16 audio tracks and the Master track simultaneously.Unlike most workstation sequencers, the Kronos's Track Data Map can show the status of all 16 MIDI tracks, all 16 audio tracks and the Master track simultaneously.

EP1: In contrast to the acoustic pianos, the electro‑mechanical pianos generated by the new EP1 engine are based on a resynthesis method that appears to be similar to the Structured Adaptive Synthesis that powered Roland's RD pianos in the late 1980s. In this, parameters are derived from the pre‑analysis of samples, and sounds are then rebuilt from these in real time when you play. But despite the complex technology behind the scenes, EP1 is incredibly simple to use. There are just three tabs of controls: the Basic page, where you select which of six pianos (three Fender Rhodes and three flavours of Wurlitzer) will form the basis of the sound; the Oscillator page, where you adjust parameters such as the attack and release noise, the hammer width, and so on; and the Panel/IFX/Amp page, which offers controls almost identical to those of the original instruments, as well as a selection of stomp‑box effects bearing names such as Small Phase (recalls the Electro Harmonix Small Stone), Orange Phase (inspired by the MXR Phase 90) and Vintage Chorus (provides a Roland CE1 Chorus feel).

I love EP1. For example, playing the Rhodes MkII through the Black Chorus (inspired by TC Electronic's Stereo Chorus/Flanger) is a joyful experience, and I doodled away an entire evening on this sound alone while writing this review. My only criticism of EP1 is the absence of Hohner Pianet and Clavinet models, so I called Korg and asked the question. The response I received boiled down to, "you've got to start somewhere”, which suggests that there could be updates in the future.

AL1: First seen in the OASYS, the AL1 virtual analogue synth seems to have become the poor relation of all the original expansion instruments, perhaps because it encapsulates everything that die‑hard analogue nutters hate about virtual analogue. For one thing, it's complex. Overflowing with morphing oscillators, multi‑mode filters with 22 filter profiles, EGs with selectable slope profiles, LFOs with nearly 200 waveform variations, multiple AMS Mixers, and much more, it was never going to reveal its secrets quickly or easily. What's more, while Korg have done everything possible to lay these facilities out clearly, it's still a long way from a knob‑twiddler's preconceptions of how an analogue synth should be programmed and controlled. Nonetheless, AL1 is a powerful synthesizer capable of imitating many revered vintage synths, as well as creating huge ranges of sounds unavailable in the heyday of analogue synthesis. My advice is to persevere... the results are worth it.

STR1: The STR1 Plucked String Synthesizer (which first appeared in the OASYS v1.1 upgrade) is based on physical models of plucked and hammered strings, so is ideal for synthesizing acoustic and electric guitars, basses, bowed strings, harps, clavinets, harpsichords, clavichords, sitars, and all manner of other stringed instruments. However, it's not limited to producing imitative sounds, and I particularly like the results that one can obtain using unworldly facilities such as samples or filtered noise as the 'excitation' source, as well as enharmonic excitations and non‑linear string models.

STR1 contains a full complement of filters, EGs, LFOs and AMS Mixers, but it's more powerful than before because you can now use streamed audio as one of its building blocks. In a different era, STR1 would have been a powerful synth in its own right, but when integrated within Kronos and used with its effects — to say nothing of being hooked up to some of the KARMA picking and strumming algorithms — it takes on a life of its own, allowing you to compose and play music in ways that you might find almost impossible without it.

The back panel of the 73‑note Kronos. On the left is an IEC port and a power switch; in the middle a pair of USB A ports and a single USB B socket; and at the right we find the bulk of the Kronos's connectivity. This includes a pair of quarter‑inch audio inputs with accompanying trim pots and mic/line buttons, four individual outputs and a stereo main output on quarter‑inch jack sockets, MIDI In, Out and Thru ports, S/PDIF I/O and three footswitch sockets.The back panel of the 73‑note Kronos. On the left is an IEC port and a power switch; in the middle a pair of USB A ports and a single USB B socket; and at the right we find the bulk of the Kronos's connectivity. This includes a pair of quarter‑inch audio inputs with accompanying trim pots and mic/line buttons, four individual outputs and a stereo main output on quarter‑inch jack sockets, MIDI In, Out and Thru ports, S/PDIF I/O and three footswitch sockets.

MOD7: Also born in the OASYS, MOD7 was released as part of its final upgrade in 2008. It was — and remains — a modular monster that combines FM synthesis with sample playback and sample mangling, waveshaping, and conventional subtractive synthesis. I suspect that few if any players have ever fully gotten to grips with it (myself included) and that's a shame because, although the learning curve is a bit steep, MOD7 can produce a fabulous array of sounds. Sure, keeping track of patchable FM algorithms is a bit mind‑bending, but it can be done and, if you want to experiment further, you can use the PCMs from the HD1 engine or even samples and streamed audio as FM operators, which leads to all manner of weird and wonderful outcomes.

MOD7 is also able to load Yamaha DX7 SysEx libraries. This means that a single EXi Program, which can support two MOD7 sounds, is equivalent to a hugely enhanced DX1 (the monster of the DX range), and you can layer multiple Programs in a Combi to emulate all eight TF1 modules in the mighty TX816, although with significantly reduced polyphony. I loaded the first four TX816 factory SysEx libraries from a USB memory stick and then layered the string and English Horn patches from the first four TF1s into a single Kronos Combi. Although this dragged the polyphony down to just five notes, the results were fabulous. You have NEVER heard FM sound so good, with such clarity and presence, and with so little accompanying noise. If I wasn't a level‑headed sort of person, I would be tempted to buy a Kronos for this alone. Bravo, Korg!

Vintage Synthesis

Two new expansion (EXs) PCM libraries provide the basis of myriad drum kits and percussion instruments, all of which can be further sculpted using the full power of the HD1 synth engine and the effects.Two new expansion (EXs) PCM libraries provide the basis of myriad drum kits and percussion instruments, all of which can be further sculpted using the full power of the HD1 synth engine and the effects.

The original Korg Legacy Collection contained 'soft' implementations of three of Korg's famous synths — the MS20, the Polysix and the Wavestation. So, given that much Wavestation technology already existed in HD1 synthesis, it wasn't a huge surprise when the MS20EX and PolysixEX became available as an OASYS upgrade.

Of course, Korg couldn't leave things alone and, when rewriting the MS20EX plug‑in as an EXi, they extended its facilities, adding new patch points, more LFOs, extra contour generators, new AMS Mixers, new audio inputs, vector synthesis, and more. Clearly, the MS20EX within OASYS was not just a virtual MS20, although it could sound like one. Happily, the MS20EX in the Kronos retains all of these extras in an improved GUI that allows you to understand and control it despite the apparent complexity on offer.

Likewise, the PolysixEX can be a remarkable synth: simple, direct and with great warmth. Whether it sounds identical with the original Polysix is no longer the issue (it can, by the way) because, once you've started throwing all of the Kronos's additional capabilities at it, emulating the original becomes just a tiny subset of what you might ask it to do.

But why include the MS20EX and PolysixEX in the Kronos at all? After all, the AL1 virtual analogue can do everything the PolysixEX can, and much of what the MS20EX can. The answer is threefold. Firstly, their characters are markedly different. Secondly, the simplicity of the PolysixEX begs even the most nervous programmer to create new sounds, while the patchability of the MS20EX encourages you to try things that you would never attempt using a modulation matrix. Thirdly, the low processor load of PolysixEX makes it the synth of choice if you want to conserve resources for elsewhere.

Finally, we come to the CX3, which Korg have been developing since the late 1970s when the original CX3 and BX3 organs were, by common consent, the best Hammond clones of the analogue era. More recently, the company released two digital equivalents, also called the CX3 and BX3, and an enhanced version of these appeared in the OASYS, where it offered all manner of enhancements. This version — which, in my opinion, remains the best and most authentic sounding of the so‑called 'clonewheel' organs — has now made its way into the Kronos. If you're happy to use sliders as drawbars, you'll not need anything else for your Hammond sounds and performances. It seems almost criminal to dismiss CX3 so briefly, but there really is nothing more to say!

Combining Sounds, Sequencing, Effects & Sampling

No matter which synth engine (or engines) you choose, Programs in the Kronos can be quite complex affairs, comprising two patches inside a common wrapper that adds vector synthesis, step sequencing, additional modulation, KARMA 2 (see box above), and of course the full power of the Kronos's effects section. In HD1, this is achieved by creating two independent oscillator/filter/amplifier patches (Double mode), but when you're using EXis you can mix two patches from whichever engines you choose. But this isn't the limit of the Kronos's Program architecture, because each Program can also include a Drum Track. Introduced on the M3, a Drum Track comprises a kit and a rhythm, each of which can be selected from the hundreds on offer. So if you like to write music on the piano and you fancy a bit of salsa today, attach a Latin kit and an appropriate rhythm to your piano of choice, and start composing. As if this were not enough, the Kronos also offers Korg's usual Combi mode, which allows you to create splits, layers and multitimbral setups of up to 16 Programs comprising a maximum of 32 sounds.

The new EP1 electric piano module provides a simple control panel based upon the original instruments, as well as a selection of appropriate stomp boxes to enhance the sound. This is a Fender Rhodes MkI played through a Small Stone phaser.The new EP1 electric piano module provides a simple control panel based upon the original instruments, as well as a selection of appropriate stomp boxes to enhance the sound. This is a Fender Rhodes MkI played through a Small Stone phaser.Of course, the Kronos is a fully‑fledged workstation, and I was delighted to find that its sequencer is based on the full OASYS system, with all 16 MIDI tracks or all 16 audio tracks simultaneously visible. What's more, the upgrade to 480ppqn timing resolution introduced on the M3 has been retained, and the maximum audio resolution has been increased from 16‑bit to 24‑bit. Maybe the Kronos doesn't quite substitute for a dedicated computer-based DAW, but it's sufficient to compose, arrange and produce music to professional standards if you're prepared to work at it. In part, this is because the effects structure in the Kronos has also reverted to that of the OASYS rather than the Triton‑esque system found in the M3. So, in addition to any dedicated effects within the sound generators themselves, the full complement of 12 assignable, routable, stereo, insert effects slots are available, together with dual Master effects and dual Total effects, plus up to 32 track EQs. Likewise, the full complement of 185 effects algorithms is retained, together with the ability to store up to 32 presets per effect module. While not truly multitimbral (which would require independent effects buses for each Program in a Combi or Sequence setup), this is still very powerful.

Tthe Kronos's sampler (which recognises Korg, Akai and Soundfont formats as well as WAV and AIFF files) is a hybrid of that in the OASYS and some improvements introduced on the M3. It uses the free RAM inside the workstation itself, which you might imagine provides lots of room for your own sounds, but that it isn't necessarily the case. As shipped, the Kronos comes with 2GB of RAM, but only 148MB is free when all the factory EXs libraries are loaded, and this equates to less than 14 minutes of stereo sampling. Happily, you can now load or sample directly to the SSD in either 16‑bit or 24‑bit WAV format, but the resulting files still need to fit into RAM if you want to use them as the basis of sampled sounds or in place of PCMs in Programs and drum kits.

Although it's not the simplest to use, there's much to like about this sampler. My favourite facility is 'In Track' sampling, which allows you to record audio, then converts it into a multisample, saves it in a Program, loads the Program into a sequencer slot, and then inserts a note into the sequence at the point at which you started sampling. I'm also grateful for 'Convert MS to Program', which does what the name implies, and the ability to resample the sound being generated while playing, or playing back sequences. Another feature that's worthy of mention is its ability to auto‑load samples into RAM at start‑up. My OASYS sits with its Mellotron Programs lying silent until I remember that I have to load the samples from the drive. Now I no longer need to do so. (Well, doubly so, because there are already some excellent Mellotron Programs based upon the Vintage Keyboards library.)

The Kronos lacks an internal CD drive, which may be inconvenient for owners of large sample libraries, but you can use an external USB CD/DVD player to load samples from discs. Unfortunately, I don't own one of these, so I transferred some files from my Mac to a USB memory stick that already held a mixture of samples, JPEGs, and even Powerpoint presentations. The Kronos recognised everything, ignored the inappropriate stuff and was able to load the audio without hiccups. Once loaded, I saved my audio and samples to the SSD, so there was no need to carry any external devices around. Consequently, my only significant gripe is that, despite a long‑standing Korg promise to load Roland‑format samples, the Kronos remains unable to do so. Actually, that's not true... I have a second gripe. The Kronos sampler/recorder retains the 48kHz sample rate from the OASYS and M3, which means that you can't burn audio directly to CD; it has to go through an intermediate sample‑rate conversion. The system does this for you automatically, but I'd much rather it wasn't necessary.

In Use

The enhanced patch panel of the MS20EX synthesiser allows you to do everything that you could on the original synth, and much more. Unlike a modulation matrix, this encourages you to try hooking things up in new and interesting ways.The enhanced patch panel of the MS20EX synthesiser allows you to do everything that you could on the original synth, and much more. Unlike a modulation matrix, this encourages you to try hooking things up in new and interesting ways.

So those are the nuts and bolts of the Kronos, although it has been impossible to do more than scratch the surface here. The specification in its preliminary manual runs to 2741 words, which is almost half the length of this review, so if I've missed out an important function here or skimmed over significant details there, it's nothing more than another indication of the number and depth of the facilities on offer. And even when you understand each section in isolation, it still doesn't tell you what it's like to use the Kronos and the disparate ways there are of using it. So here are a few observations that I hope will give you some flavour of what it's like to program and play it.

Let's start with the control panel. Apart from the loss of the luxury hardware and sexy cosmetics, the major difference between the Kronos and the OASYS is that the new model's screen is significantly smaller and mounted flush with the panel. This isn't a problem, but it's a shame, because synths with angled screens tend to be easier to use. A second look also reveals that the OASYS's velocity‑sensitive pads have gone. Nonetheless, it's clear that the two panels are designed to do the same job, and I found it effortless to switch from one to the other.

Elsewhere, there are equally significant hardware differences. The omission of the CD drive is understandable, but then there's the reduction from 10 outputs to six (which may be a limitation for players outputting multiple Programs simultaneously to an external DAW or live‑sound desk) and the loss of two of the OASYS's mic/line inputs, as well as the XLR sockets for the two that remain. Likewise, two of the OASYS's USB ports have gone, as has its ADAT expansion capability, but I'm not concerned by these omissions. The Kronos's two Type A and single Type B USB ports, the latter of which allows audio streaming and MIDI connection to external computers and other devices, are a better choice for the modern studio.

Turning to the software, the Kronos is almost identical to its predecessor. Even the factory sounds in each of the common synth engines are largely the same, with not just the same controls on all of the same pages, but the same values for all of the controls, and the same control highlighted when you access each page. Nevertheless, the Kronos offers a number of new features that in some ways make it an even better instrument than the OASYS, particularly for on‑stage use. Most important in this regard are the Set Lists. There are 128 of these, each of which can hold up to 128 items (Programs, Combis or Songs) that you can select by hand or step through using a footswitch. Not just a good way of organising sounds, the lists offer space for comments or lyrics, and allow you to determine how one sound will be curtailed when you select the next. Discovering this at the start of the review made me wonder, will the Kronos continue to play held notes correctly — including all of their effects — when you change to the next Program or Combi? Yes, it will. This is something that the OASYS cannot do, and it's an important improvement.

But for most people, it's the combination of immediacy of use, the range and quality of the sound generation and effects, and the quality of the sampling, recording and sequencing that defines a workstation. So how does the Kronos score on these points?

AL1 is a deep, complex and sometimes daunting 'virtual analogue' synthesizer, but it's worth getting to know because the range of options available make it more flexible and more capable than most hardware VA synths or plug‑ins .AL1 is a deep, complex and sometimes daunting 'virtual analogue' synthesizer, but it's worth getting to know because the range of options available make it more flexible and more capable than most hardware VA synths or plug‑ins .Let's start with immediacy. There's a die‑hard school of analogue synthesists who demand knobs for every function, and the Kronos is not for them. But for the rest of us, its combination of a touchscreen and a panel with nearly 100 buttons, knobs and faders — not to mention two joysticks and a ribbon controller — is more than adequate. Having owned an OASYS for six years, I have a head start on most people but, for all its apparent complexity, the Kronos is not difficult to grasp, and most new owners should be able to get up to speed without too much hassle.

What about the range and quality of the sounds available? Is the Kronos a powerful VA synth? Yes, three times over. Is it a state‑of‑the‑art piano? Again, yes. Is it a superb electro‑mechanical piano? Yes. An unsurpassed clonewheel organ? Yes. A powerful FM synth? Yes. An even more powerful PCM‑based synth? Again, yes... and that's a particularly interesting aspect of the Kronos. Korg have often led the way in developing new sounds and textures, but have equally often fallen short in areas such as orchestral sounds. With the addition of the Kronos's new EXs libraries, I suspect that the manufacturers whose orchestral sounds have been the de facto standards for 20 years or more may now have more competition.

So that, then, leaves facilities such as sampling, audio recording, MIDI sequencing, and composition tools such as KARMA and Drum Tracks. I doubt that anyone has ever fully plumbed these facilities in the OASYS and M3, and I suspect that there's enough here to keep you experimenting, playing and composing until someone develops a USB cable that you can plug directly into your brain. That's not to say that the Kronos does everything. For example, there are facilities in the Roland V‑Synth XT that would be welcome additions on other manufacturers' flagships. But if I were ever to be stuck on that mythical desert island, a Kronos 88, a decent sound system and a working 13A mains socket would be more than enough to keep me occupied until Claudia Schiffer hove into view on her otherwise crewless 80-foot yacht.

Of course, the Kronos isn't perfect. I've mentioned a few issues above, and there are two others worth mentioning. Firstly, it takes a long time to boot — two minutes 15 seconds for the review unit — which would be embarrassing if there were a power glitch that required a restart on stage. Secondly, I found the noise from its motherboard fan a bit annoying, so I could see myself switching it off for critical studio listening. But these complaints aside, it's hard not to eulogise about the sounds and facilities on offer. And finally, I need to compliment Korg on the quality of the pre‑production software in the review unit. Despite being warned that it might have a few minor issues that would be resolved before release, it didn't do anything untoward at any time during the review. You can't say that about some manufacturers' products three months after release, let alone three months before!


The Kronos offers plenty of opportunity for hands‑on control, providing two joysticks, a ribbon controller, a selection of knobs and faders, a generous array of buttons and, of course, the central touchscreen.The Kronos offers plenty of opportunity for hands‑on control, providing two joysticks, a ribbon controller, a selection of knobs and faders, a generous array of buttons and, of course, the central touchscreen.

We keyboard players are a funny lot, and never was this more obvious than when Korg allowed the first sounds from the Kronos to trickle out into the world. But what was it? Based on what they heard, enthusiasts speculated that it was an updated Wavestation, a new Karma, some form of vector synth, a hardware‑based Legacy Collection, and even a sampler/resynthesizer. Another popular idea was that it would be an updated MS20 with MIDI, memories and advanced effects, and one person even went so far as to state that this would be the only product that anybody would ever want from Korg. We now know that they were all correct; well, all except the MS20 extremists. So, when it was revealed, did the synth aficionados of the world cheer? No. Having been presented with something that has the potential to be the most flexible sound source and music-production keyboard yet developed, many greeted it with caution. But they're the ones who are going to miss out, and here's why...

Throughout this review I have been comparing the Kronos to the OASYS, which I am able to do because, having reviewed it in 2005, I bought one. And, as far as I am concerned, it remains the sexiest, best sounding and most desirable workstation yet developed. But today, the Kronos — while foregoing the gorgeous and unusual OASYS physical design — retains all the audio quality of the OASYS. It also offers the expanded PCM libraries for the HD1 engine, the excellent SGX1 pianos, the fabulous EP1 electric piano engine, set lists, improved audio handling, and more. In other words, it's more flexible and in many respects more powerful than the OASYS. Yet it no longer occupies the stratosphere of synth prices; indeed, it appears that it will cost little more than its (supposed) competition, with Korg anticipating that the range will be priced from around £3000it costs little more than its (supposed) competition. So while there's nothing surprising about the Kronos — it's an enhancement of existing technology — I'm impressed. I mean... really impressed. I need to lie down for a while.  


With all due respect to some excellent workstations from other manufacturers there is, as far as I am aware, no direct equivalent to the Kronos. The best of the rest are, for me, the Roland Fantom G7 and the Kurzweil PC3x, both of which can also sound superb. But while these offer a number of similar facilities, neither offers the range of synthesis engines, nor the composition tools, nor the audio integration of the Kronos, in which the traditional dividing lines that separate PCM‑based synthesis, physical modelling synthesis, sampling, audio recording, and audio streaming have become so blurred as to be interchangeable for many purposes.

Of course, you might contend that a PC‑based system such as Open Labs' Neko — or even a powerful PC with appropriate host software and plug‑ins — allows you to combine multiple synthesis engines and sampling, as well as audio and MIDI sequencing. But this again lacks the integration of the Kronos, and a Mac or a PC (whether housed in a conventional case or with a five‑octave keyboard glued on the front) is not the same as a dedicated keyboard workstation whose real‑time performance is assured, even when everything is running flat out.

Maximum Polyphony

There has been much speculation regarding the maximum polyphony of the Kronos and how this compares with the OASYS. In general, the Kronos manages slightly lower polyphony, but not by huge amounts. For example, HD1 polyphony on the Kronos is 140 notes and on the OASYS 172, while the AL1 synth figures are 80 and 96 respectively and those for MOD7 are the same, at 52. The Kronos's CX3 synth actually offers more polyphony, at 200 notes compared to the OASYS's 172. The published figures do not tell the whole story, because the OASYS is affected by the use of power‑hungry effects, whereas Korg claim the Kronos is less susceptible to this. Note that the Kronos distributes its resources as best it can, so if half its processing power is being used by one of the engines, only half will be available for the others, and the polyphony offered by each will be reduced accordingly.

Kronos Keyboards

The Kronos will come in three flavours. The first will be the 61‑note, semi‑weighted version reviewed here. The flagship of the range will be an 88‑note version that will use the excellent RH3 keyboard already used in the M3 and the SV1, so if you're planning to use the Kronos as a stage piano, this will probably be the one for you. The model in the middle will use the truncated, 73‑note RH3 keyboard first seen on the smaller of the two SV1s. This is great for electro‑mechanical pianos, but a fully‑weighted action is not ideal for playing organs or synth solos. Given that the middle of the range has traditionally been a 76‑note, semi‑weighted model, Korg have either had great foresight or have been a bit misguided in bucking the trend. Time will tell.

KARMA 2 Explained

The simplest way to describe KARMA 2 is as a complex arpeggiator that, instead of playing static sequences of notes, generates quasi‑random elements to emulate what a human player might do when presented with the need to play a similar phrase or pattern. With eight scenes per Program, a KARMA module can create anything from simple arpeggios to complex performances. When used within a Combi, up to four modules can be applied, to create anything from evolving soundscapes to auto-accompaniments of whole bands and orchestras.

KARMA 2 generates its effects using a set of algorithms called Generated Effects (or GEs). There are 2048 preset GEs in the Kronos, and space for another 1536 user‑defined ones. If you can get past the initial hurdles, you may never stop finding things to do with them.

Guts Of The Kronos

The Kronos is, as the OASYS was before it, essentially a PC in a keyboard‑shaped box. Rather than using the Core processor (the direct descendant of the P4 used in the OASYS), Korg have adopted the Intel Atom for the Kronos. Although this choice has been criticised elsewhere, I think it's an astute one, because the Atom is small, uses less power than a Core, runs cooler, and is less expensive. Sure, for any given clock rate it's less powerful, too, but since Korg have avoided the power-sucking monster that is Windows and run optimised code in a Linux environment, the swings outweigh the roundabouts, both in terms of price and of performance.

Kronos Upgrades

The Kronos is highly upgradable. Installing any forthcoming EXs libraries should be a doddle, and new synth engines could also appear, should Korg decide to develop them. As for the hardware, the provision of USB means that you can add external devices to extend its functionality, and increasing the internal memory should also be possible. There have been no announcements regarding expansion as yet, but I can't believe that Korg would be unaware of users' interest in this, especially where the issue of PCM and sample RAM is concerned.


Korg appear to have been careful to avoid calling the Kronos the OASYS MkII, which would have been just as appropriate. I suspect that there is a commercial reason for this. If they had done so, it would have been reasonable for OASYS owners to expect some or all of the Kronos's new libraries and facilities to be made available as upgrades. By divorcing one from the other, the company are, in effect, saying, "How can we put Kronos inside OASYS? They are different products.” As an OASYS owner, I hope I'm proved wrong.

Abridged Kronos Specification

Keyboard: 61‑key semi‑weighted; 73‑ and 88‑key piano‑weighted.
HD1 Synth Engine 314MB ROM, 1505 multisamples, 1388 drum samples.
Expansion Libraries EXs1 ROM expansion; EXs2 Concert Grand Piano; EXs3 Brass & Woodwinds; EXs4 Vintage Keyboards; EXs5 ROM Expansion 2; EXs6 SGX1 German D Piano; EXs7 SGX1 Japanese C Piano; EXs8 Rock Ambience Drums; EXs9 Jazz Ambience Drums.
Wave Sequences 165 preset, 374 user.
Expansion Instruments: SGX1 acoustic pianos, EP1 electro‑mechanical pianos, AL1 virtual analogue synthesizer, MOD7 FM synthesizer, STR1 plucked string synthesizer, MS20EX virtual analogue synthesizer, PolysixEX virtual analogue synthesizer, CX3 virtual tonewheel organ.
Internal RAM 2GB.
Available Sample RAM 148MB after factory libraries loaded.
Internal Drive 30GB SSD.
Memory 1664 Programs, 1792 Combis, 152 Drum kits, 256 GM2 Programs and nine GM2 drum kits.
Set Lists 128 lists, 128 slots per list.
Sampling 48kHz, 16-/24‑bit, 4000 samples, 1000 multisamples maximum
Effects Insert Effects: 12; Master Effects: two; Total Effects: two. 185 different types with side‑chaining; 783 presets, maximum 32 presets per type. EQs: one per track.
KARMA 2048 preset Generated Effects (GEs), 1536 User GEs, one module in Program mode, four modules in Combi and Sequencer modes.
Drum Tracks 697 preset patterns, 1000 user patterns.
Sequencer/Recorder 16‑track MIDI sequencer, 16‑track hard disk recorder, master track. Four‑track simultaneous recording, maximum 200 songs, 300,000 audio events, 400,000 MIDI events. Resolution: 480ppqn. Real-time Pattern Play and Record (RPPR): 1 Pattern set per song.
Screen TouchView, eight-inch TFT, 800x600 pixels.
Analogue Outputs Main L/R, four individual, headphones.
Analogue Inputs Two quarter‑inch TRS balanced jacks.
Optical S/PDIF In & Out, 24‑bit, 48kHz.
Control Inputs Damper, assignable switch, assignable pedal.
MIDI (DIN) In, Out, Thru.
USB A Two connections to external USB devices.
USB B MIDI & two‑channel audio interface, 24‑bit, 48kHz.


  • The expanded HD1 libraries are superb.
  • Korg's pianos are finally up there with the best of them... as are their orchestral sounds.
  • The EP1 piano engine would justify a keyboard in its own right.
  • It offers fabulous FM capabilities.
  • It offers three flavours of virtual analogue, including the enhanced MS20 soft synth.
  • It includes the best of the 'clonewheel' organs.
  • Its workstation capabilities are unsurpassed.
  • Transitions are now smooth when changing sounds during performance.


  • It takes a long time to boot.
  • A quieter fan wouldn't go amiss.
  • Its screen can't be angled.
  • There's no built‑in CD/DVD drive.
  • Even today, polyphony can drop as low as a single handful of notes.


Given that Korg have discontinued the OASYS, all I need say is, 'The king is dead, long live the king.'


Expected to start at around £3000.

Korg +44 (0)1908 857100.

Kronos 61-note $3750, 73-note $4350, 88-note $4750. Prices are MSRP.

Korg +1 (631) 390 8737.