By Stephen Fortner
Honey, they shrunk the OASYS. Well, its weight and physical size.
In nearly all other respects, the Kronos, which debuted at Winter
NAMM 2011, equals or surpasses the features and sounds of Korg’s
groundbreaking (and now discontinued) do-it-all behemoth. More
significantly, Korg shrunk the price from the OASYS’ rock-stars-only
$8,000 to a level that’s competitive with the other flagship workstations
and multi-sound-engine gig keyboards currently on the market. Let’s
dive in and try to answer the intentionally provocative question we
asked on this issue’s cover.
Got a gig that requires a tuxedo? With its piano-black cheek blocks,
burnished gun-metal body, and icy white LEDs that light the buttons
and main joystick, the Kronos looks like it’s already wearing one. In
the studio, the printing on the panel looked readable enough, but
tended to wash out under changing stage lighting. Fortunately, the
“Control Surface” view is an onscreen duplicate of the knobs, faders,
and all the buttons that select pages of functions for them. You can see
(and change) all the assignments from here, and thanks to the visual
correspondence between screen and panel, the Control Surface view is
the best way to get fluent in using the physical controls.
The OASYS’ touchscreen was larger, but the Kronos’ is higher-res:
800 x 600 as opposed to 640 x 480. Th ose extra pixels make small fonts
more legible. Single-touch operation may seem old school, but unlike
today’s smartphones, you can navigate the Kronos with a stylus or
fingernail, which I found works best when selecting stuff from optionpacked
pop-out menus. The screen almost always refreshes instantly
when you do something—some other keyboards have some catching
up to do there.
Editing is made easier by several ways of changing values. Let’s say
you tap a filter cutoff knob onscreen. The Value fader to the display’s
left will sweep it quickly, while the main data dial to the right moves
it slowly—coarse and fine. You can also use the increment buttons, or
type exact values on the keypad.
The only physical controls you give up compared to the OASYS are
the velocity-sensitive pads that triggered drums or memorized chords.
In their place is a touchscreen page with eight playable strips—the
vertical axis translates to velocity.
I will say that Korg has favored a low-profile look over a touchable
feel—I prefer the chunky, rubbery knob and fader caps on the Yamaha
Motif ES and subsequent models, not to mention the slightly longer
throw of their faders. Points for the Tap Tempo button, but what—no
dedicated octave shift buttons? Instead, the assignable switches above the
pitch/modulation joystick do this on a per-sound basis.
The Kronos comes closer to the experience of having a music laptop
stocked with your favorite virtual instruments than any self-contained
keyboard yet has, minus the usual computer headaches. Seven of the
nine instruments here were either originally part of the OASYS or later
released as expansions for it, but the first two—the SGX-1 acoustic pianos
and EP-1 electric pianos—are exclusive to the Kronos.
SGX-1 pianos. For me, the “bank A,
program 1” acoustic piano sound
has never been the strong suit of
Korg workstations. Good enough
for the gig, but no industry leader.
The Kronos does a dramatic 180,
with the best sounding factory
pianos ever to show up in a workstation.
The two main piano flavors are full-bodied “German” and brighter
“Japanese” grands. Both sound gorgeously detailed in recordings, and the
brighter variants of each cut through a live rock mix without sounding
brittle. Each piano streams 4.7GB of full-length samples from the
internal solid-state drive, so you’ll hear no loops, no phase weirdness,
no unnatural decay, and no clunker notes with skewed harmonics.
Switches between the eight velocity layers are nigh imperceptible.
Lid position, sustain pedal resonance, mechanical noise, and
release sample volume are all adjustable, as is whether you hear the
stereo picture from the audience or player’s position. The best pianos
in a plug-in like Synthogy Ivory use several times more memory, and
you will hear that difference listening carefully to solo piano pieces. I
also wouldn’t say the Kronos deals a clear drubbing to high-end digital
pianos like the Roland V-Piano or Yamaha CP1. But the fact that those
are more relevant comparisons than other workstations—and they
are—is really saying something.
EP-1 electric pianos. Th e
mighty OASYS relied on
for its vintage electric
pianos. EP-1 is in a
whole other league. Two reed (Wurlitzer) and four tine (Rhodes) pianos
are on hand, including a Dyno. Details you can tweak include hammer
width, attack brightness, and release noise. You can insert one of nine
virtual stompboxes, including the must-have MXR Phase 90, and
cabinet modeling simulates either the Fender Suitcase amp or the internal
speakers of a Wurly. How does it all sound? Real. Bass bark and mid-high
pop jumps out of the speakers when you spank the keys. Play delicately,
and you’ll get beautiful ballad timbres. Ask for the dynamic range between
those extremes, and you’ll get all of it. A+.
CX-3 organ. Korg recently
discontinued the “new”
CX-3 as a standalone B-3
clone, but it lives on inside
the Kronos. You get splittable
upper and lower drawbar parts (but no bass pedal part), and Korg’s EX
drawbars if you want to add four harmonics not found on the real thing.
Sonic details such as leakage, percussion, and vibrato/chorus are deeply
editable, as is rotary simulation—you get separate speeds, speed-up
and slowdown times, and mic placement settings for the treble and
I give the organ model itself a grade of A, and the rotary effect a solid
B+. It was one of the best available when Korg introduced the new
CX-3, will still make organ fans at any live gig wonder where you hid the
Leslie, and is certainly as good as it gets on any workstation. Listening
in isolation, though, I felt that a couple of dedicated clones I’d recently
reviewed (the Studiologic Numa Organ and Nord C2, both in May ’11)
treated high frequencies a bit more realistically at fast rotary speed.
AL-1 synth. Any attempt to
describe this analog-modeling
monster concisely is doomed to
be a gross understatement of its
depth. Just a few highlights are
two oscillators with continuously
variable waveforms; a suboscillator
you can swap for external audio input; dual multimode filters
with serial or parallel routing, plus a “Multi-Filter” that can morph
between two types in real time; hard sync and audio-rate FM; five fivesegment
envelopes; and seemingly bottomless modulation options,
including a step sequencer that can “play” any eligible destination.
More significant than any of this is the sound quality of the modeled
waveforms and filters. It’s simply unparalleled. There’s no appreciable
aliasing, even on very high notes, and no stepping or zipper noise
when you sweep parameters. To sound any more analog than this, you
need a real analog synth.
PolysixEX and MS-
20EX synths. Know
what I don’t like about
these replicas of Korg’s
classic Polysix and MS-20
analog synths? Nothing!
In short, they sound like
the originals. Only with
more polyphony and the ability to be layered with other sounds,
routed through effects, and modulated a zillion ways from Sunday.
Korg elegantly handles the MS-20’s patch panel on the touchscreen:
Tap any jack twice, and a flashing yellow square surrounds it. Tap the
second jack, a patch cable appears, and your connection is made.
The Kronos won’t let you do things that don’t make sense, like
connecting two outputs together. If you’re new to synth programming,
either of these synths serves up more instant gratification than AL-1,
and both have markedly different sonic characters as well.
MOD-7 VPM synth. Imagine
a Yamaha DX7 with a modular
patch panel that lets you alter
or override the algorithms for
how the operators interact.
Imagine that the operators
could make not just sine waves
as on the DX7, but saw, square, and triangle—or use a waveshaper
to get more harmonically complex results. Imagine you could also
use multisamples as modulators, or just patch them in as a separate
layer. That’s the very tip of the iceberg of MOD-7, a variable phase
modulation (VPM) waveshaping synth. If you don’t need a sound
designer’s paradise, just enjoy the factory sounds, which range from
DX-like to surprisingly analog sounding—a testament to how sonically
versatile FM synthesis can be. The kicker: If you can get original DX7
sys-ex files onto a USB drive, MOD-7 will load the sound banks.
STR-1 string modeler. I could joke about “string theory” in quantum
physics, but in fact, Korg’s modeling synth for plucked strings is a little
easier to understand. “Plucked” understates its capabilities, as it can
also sound like the virtual strings were struck, bowed, scraped with car
keys, or vibrated in other ways. Anything from acoustic guitars to John
Cage-style prepared pianos to resonant drones reminiscent of Star Trek:
The Motion Picture is possible. You can decide not only what kind of
string is used, but how and where it’s “excited” as well. Similar to MOD-7,
you can layer a PCM sample, or actually use its attack transient as your
“pick.” Bonus: Both MOD-7 and STR-1 give you the same dual filter
setup, including the Multi-Filter, as AL-1.
HD-1 engine. All the previous sound engines come under the
umbrella term “EXi” for “expansion instruments,”—ironic, because it
implies they’re add-ons when they seem more like the star attractions.
The Kronos also packs the core sampling engine from the OASYS,
called HD-1. An HD-1 program can have one or two “oscillators.”
An oscillator is really a complete synthesizer that plays up to eight
velocity-crossfaded multisamples, any two of which can “speak” as a
non-switched, full-time layer. Any of the eight slots can also hold a
tempo-synced wave sequence. You effectively get all of the moving,
morphing madness of Korg’s classic Wavestation synth, as you did
on the OASYS.
On the Kronos’ internal solid-state drive, you’ll find every EXs sound
expansion pack Korg created for HD-1 since the OASYS era; the new ESx4
Vintage Keyboards library is my favorite, and I like its Clavinets better than
any that the STR-1 string modeler can cook up. (Korg, please make
an EXi that does for Clavs what EP-1 does for electric pianos!) The
Kronos preloads selected instruments on power-up into the 2GB of
sample RAM—there’s actually no factory ROM. Officially, sample RAM
isn’t user-expandable, though some clever folks at korgforums.com have
done this (and installed larger SSD drives) fairly painlessly. Since opening
the Kronos will void your warranty, we recommend waiting for Korg to
make any expansion options official.
I could take up the rest of this issue describing the variety of sounds in
the Kronos. Instead, I’ll call out what they all have in common: pristine
audio fidelity. From synths to saxes, pianos to piccolos, and tympani to
TR-808s, everything sounds smooth, rich, and not at all grainy. Things
that are supposed to be punchy, like kick drums and synth bass, kick
you in the gut. Things that are supposed to be crystalline, like wave
sequences you’d layer over pads, swirl around your head. Things that
are supposed to be warm, like analog brass, are.
Is there any sound category where the Kronos could do better? Acoustic
and electric guitars come to mind. The best specimens come from the
STR-1 string modeler, but somewhat surprisingly, my aging Motif ES has
more of what I want to hear in this area. Also, while the acoustic string,
brass, and woodwind patches (all from the HD-1 engine) offer lots of
variety for pop and R&B lines, I’d like to see more power-user features for
these sounds, such as proactive, realtime articulation management, voice
allocation for divisi, and other stuff a composer would want for serious
mockups of orchestral scores. Roland’s “SuperNatural” and Yamaha’s
“Expanded Articulation” technology have some of these moves, and the
Kronos’ stellar job on piano, keyboard, and synth sounds is raising my
expectations here. There’s no reason a future Kronos EXi couldn’t work
similar magic for orchestral sounds.
Usually, no matter how good a keyboard’s sounds are individually, if you
do an entire multitrack production on one instrument, the results will sound
kind of glassy. Some audio experts blame it on hearing everything through
the same digital-to-analog converters. Whatever the reason, the Kronos
seems to suffer from this less than any other keyboard in recent memory.
Its EXi instruments have distinct enough characters to create a convincing
illusion that your all-in-the-box song used a bunch of different keyboards.
“Smooth sound transition” is Korg’s term for the fact that changing
sounds doesn’t cut off sustained notes. Other keyboards have done this,
but the Kronos is especially fluid. You won’t even hear any audio “bump”
normally caused by effects switching, and it works in all play modes
regardless of whether you change sounds with the dial or increment
buttons, by tapping a slot in a Set List or the category browser, or via
the numeric keypad. It only retains notes from the most recent sound
played, so two consecutive program changes will cut off the audio—of
the first program but not the middle one. This is the best implementation
yet of a feature that should be required on all keyboards by law.
On the Kronos, a program can be what’s effectively a two-way combi—
though it lives in a single program slot and you’re not in Combi mode.
Th is can be quicker and more intuitive than dealing with all the options
of Combi mode, especially if all you’re after is a simple split or layer.
With EXi sounds, you can simply touch-select a second instrument
(SGX-1, EP-1, etc.) under “EXi2” on the “Common” page and just start
tweaking until it sounds good. Better, if you remember a layer you like
from some other program, use the “Copy EXi Oscillator” function to
grab it with all its settings intact. I do wish this function let you browse
sounds by category as you otherwise can on the Kronos, but it’s by
bank and number only. You can also quickly set keyboard zones for
each instrument, and mix their volumes using the first two faders.
You can stack any two EXi instruments, or create dual HD-1
programs, but you can’t combine EXi and HD-1 sounds in the same
program. (In fact, HD-1 and EXi programs have to live in different
banks.) Of course, you can pop up to Combi mode and freely combine
programs that use EXi and HD-1 sounds. All in all, creating dual
programs feels less like “programming” and more like being in a virtual
music store, happily stacking keyboards atop one another.
The Kronos’ facilities here are more like a computer-based DAW
than any other keyboard workstation’s are. Alongside the usual 16
MIDI sequencer tracks, you can record up to 16 audio tracks to the
internal solid-state drive. Audio tracks are mono, but you can link them
in stereo pairs. Up to four tracks can be recorded at once, and 24-bit
resolution is now supported, though the sample rate is still fixed at 48kHz.
Th e two balanced 1/4" audio inputs around back each have a trim pot and
mic/line switch, but neither handles high-impedance signals, so you’ll
need a preamp to get proper tone from most electric guitars. Other input
choices include optical S/PDIF, any of the Kronos’ internal busses, and
even streaming over USB, as the Kronos is also a USB 2.0 audio interface.
Audio and MIDI track mixers are on separate screens for space
reasons, but a unified Track Edit view shows all tracks together, along
with the master track that handles such things as in-song tempo
changes. Here, you can issue track-based, measure-based, and (for
MIDI) note-based editing commands, as well as do step recording.
Some commands take you a level deeper, where you’ll find features like
a MIDI event list and zoomable audio wave editors.
Th e sequencer/recorder is so similar to the OASYS—virtually identical,
in fact—that instead of excavating more features I’ll just say that recording
on a standalone keyboard doesn’t get more powerful than this. Any nitpicks
I have don’t concern what you can or can’t do, but occasional quirks of how
you do it. For example, I’d prefer that touching the onscreen fader for a given
MIDI track let you play its sound on the keyboard. Instead, you have to
select the track from a pop-out browser above the mixer area. Along similar
lines, the Track Edit overview could use a zoom function and a more visible
play wiper than that little yellow dot that ticks across the timeline.
Both for sheer effects power and for handling routing, the Kronos slams
it out of the park. You can run up to 12 insert effects simultaneously,
plus two “master” (send-based) effects. Then, two “total” effects are on
the final output, downstream of any other routing. Good choices for
this stage include a multiband compressor, mastering limiter, reverb,
or any other final spit ’n’ polish.
Best of all, when dealing with complex songs or combis, or
processing external audio through the effects, you can bring up routing
diagrams (shown above) that make it crystal clear what’s going through
what—no small feat given the extensive bussing possibilities. As to
effect types, about the only thing I couldn’t find was convolution reverb
(though there are plenty of conventional reverb options), probably
because it’s such a CPU-hungry process. For overall sound quality,
these effects easily compete with many dedicated plug-ins.
Even though we’re running out of room and the following features
aren’t new to the Kronos, I’d be remiss not to mention them, as they
add to the playing and composing experience.
KARMA 2. For the uninitiated, this latest iteration of programmer
Stephen Kay’s realtime music generator can be oversimplified as a
multitimbral, polyphonic arpeggiator on
steroids—hence this section’s title! Depending
on how it’s set up, it can sound close to arranger
auto-accompaniment, create choppy dance
floor effects, roller-coaster into unexpected
musical twists, or do anything in between. It’s
a world unto itself, and you can learn how it
works at karma-lab.com.
Drum Track. Want straight-ahead rhythmic
accompaniment? Either preset or user-created
drum patterns can be set to play when you hit the
keys. You can set the keyboard zone that triggers
the pattern to start, mix any pattern with any
kit, and even transpose the drum map by halfsteps
with the Shift parameter, resulting in subtle
to dramatic changes in the hits. Note that with
some programs, KARMA will have drumming
plans of its own even if the Drum Track isn’t
active—though you can sync the two up.
RPPR. Short for “Realtime Pattern Play/
Record,” this long-standing Korg feature
lets you record patterns using the sequencer,
then assign them to keys for tempo-synced
triggering. Patterns can also be set to trigger
at pre-determined points in an otherwise
linear song recording.
In-track sampling. One of the many abilities of
the Kronos’ full-featured sampler is to assign a
given bit of sampled audio for triggering via
a MIDI note in the sequencer. In ReCycle
fashion, you can also slice audio according
to the transient peaks, then trigger each
slice separately, or time-stretch the lot to
Vector joystick. Able to map multiple
parameters to its X and Y axes, the Kronos’
“other” joystick is, at minimum, a high-powered
macro-morpher. The “vector envelope” can even
automate a series of joystick moves in sync with
tempo. As on the classic Wavestation, vector
envelopes are used to particularly animated
effect with wave sequences, but nearly every
program in the Kronos employs this joystick
in some musically pleasing way.
AMS. “Alternate Modulation Sources” is
Korg’s term for programmable modulation
routings—they’re alternate relative to the
defaults. The real power is in the AMS mixer,
which is how you tell the Kronos, “Modulate
this with that, by way of another thing.” A
simple example is vibrato: varying oscillator
pitch via an LFO, with the joystick controlling
depth. But the selectable mixer algorithms can
get much more sophisticated about how the
two modulation sources interact—they can
add up, multiply, off set one other, or use more
complex if-then logic. Maybe only hardcore
sound designers will spelunk this deeply, but
it’s nice to know that whether you’re an audio
mad scientist or just want awesome Rhodes
and synth sounds for “Living for the City,” the
Kronos isn’t about to let you down.
Every once in awhile, a pivotal instrument
truly raises the bar, and thus sets the tone for
future industry competition, about what a
given type of keyboard—workstation, analog
synth, drawbar organ, stage piano—can and
should do. This sure feels like one of those
times. As discussed, there are some acoustic
sounds the Kronos doesn’t render with the
highest standard of playing realism—at least
not right now. But right now, if I had to pick
one keyboard to be marooned with on a desert
island, the Kronos would be it. No other single
product does this much, this well, all at the
same time, at this price or anything close to it.
That’s our definition of a Key Buy.
PROS Best acoustic pianos ever in a workstation. Electric pianos and drawbar
organs could justify a keyboard in their own right; so could the virtual analog
synths. Overall sound quality and diversity are stunning. Does 16-track audio
recording. Lots of effects, and they all sound great. Plenty of polyphony for
multiple synth types in a song or combi.
CONS Sample preload on power-up is convenient, but makes for long boot time.
Neither sample RAM nor internal SSD are user-upgradeable. Segregation
between HD-1 and EXi programs seems odd. Difficult but not impossible to
hit that polyphony ceiling with dense songs or combis.
POLYPHONY Varies with instrument type; 80–200 voices.
RECORDING 16 MIDI tracks plus 16 audio tracks. Extensive automation
and MIDI filtering. Track, measure, note, and audio waveform editing.
SAMPLING Full audio processing and editing functions, including sampleto-
track and assigning loop slices to MIDI notes. Can sample to 2GB RAM or 30GB SSD.
SIMULTANEOUS EFFECTS 16 (12 insert, 2 master, 2 total).
PRICE 61 keys | List: $3,499 | Approx. street: $3,000
73 keys | List: $4,350 | Approx. street: $3,500
88 keys | List: $4,750 | Approx. street: $3,800
Korg may not have been first with a unified mode to access
anything you need for the gig: patches, combis, or sequencer
songs. Kurzweil’s Quick Access banks and Yamaha’s
Master mode are similar ideas. The Kronos’ Set Lists
take the idea to new heights, though. A Set List can have up
to 128 touch-access slots in groups of 16 per screen. You
can enter a name of up to 24 characters (e.g., a song title)
and add notes of up to 512 characters—useful for a few lines
of forget-prone lyrics. You can’t drag-move slots like they’re
iPhone apps, but copy and paste functions let you reorder
them. Last but not least, a nine-band EQ is exclusive to this
mode and affects all slots in the Set List. This lets you grab
the faders and adjust to the room acoustics without dealing
with individual programs’ EQ settings.
Korg put fully weighted keys on both their 88 and their midsized
(73-key) model, something we see on gig keyboards
like the Nord Stage but not usually on full workstations. I
found Korg’s RH3 action very non-fatiguing even for extended
piano practice, and just right for electric piano sounds.
My synth-accustomed fingers would have preferred a bit
less weight for organ and synth licks, as I had to play more
deliberately and thus more slowly. A 61-key semi-weighted
Kronos is also available, of course. The aftertouch did a
good job of translating the full range of finger pressure to
smooth sonic changes, as opposed to going too quickly
from zero to full.
*Video: First impressions in the studio.