Is the Physis K series the most professional MIDI controller now made?


PROS: Extremely deep MIDI programming possibilities. Great feeling keyboard with aftertouch. Eight five-pin MIDI output ports and eight pedal inputs. Expansion board offers physically modeled sounds including great Rhodes and Wurly electric pianos.

CONS: USB-to-computer connection currently provides only one virtual MIDI port (16 channels). Expansion board’s acoustic piano modeling may not be to your liking. No drum pads. Not cheap.

BOTTOM LINE: If you have lots of MIDI hardware, this is the sort of hyper-professional master keyboard we previously thought no one made anymore.

K4 (88 keys): $2,795 list | $2,250 street | K4EX: $3,795 list | $3,250 street } K5 (76 keys): $2,595 list | $1,950 street | K5EX: $3,495 list | $2,990 street |

There’s a new contender in the master keyboard controller category, and it’s a serious piece of gear. The Viscount Physis range of controller keyboards includes the K4 (88-note weighted action), K5 (76-note semi-weighted action) and EX versions of both models, which include a sound expansion board featuring physically modeled acoustic and electric pianos and more. Both units are eight-zone MIDI master keyboards with a wealth of front-panel controllers, pedal inputs, MIDI I/O, and more. These are very deep and capable units, and I’ll cover as much as space permits.

Front Panel

I received a K4EX to review; the K5 (my editor’s choice for the main photo) differs only in the keyboard length and mechanism. These are substantial pieces of hardware, with a rugged metal case sporting recessed sides to aid carrying. That’s good, since the instrument weighs in at 43 pounds. The Fatar TP-40L keybed contributes to that, with a great-feeling hammer action that provides for initial velocity, release velocity, and channel aftertouch (the K5 uses the Fatar TP-100LR, a somewhat lighter action). As a reality check, I looked up most of the more “pro” stage pianos and the K4EX is no heavier than most (Casio PX-5S excepted), and lighter and more compact than many of them.

Across the front panel you’ll find three assignable wheels, the first spring-loaded like a pitch-bend, the other two free-moving. A volume slider controls the optional EX internal sound board, but you can’t assign it to output controller messages—why not? The main controller section provides nine each of endless encoder knobs, 45mm sliders, and buttons, which can be configured in four banks of message setups. Yup, that’s 108 possible messages. But wait, there’s more. Each controller can send a different message per zone, so we’re up to 864 messages. Of course I’m playing “specsmanship” here—you’re not likely to need to do so much at one time. But the K4 tends to over-deliver.

I liked having dedicated buttons for selecting and enabling/disabling the eight zones, with lights to indicate on (blue), muted (red), or off (unlit). A View button toggles whether you see a single zone’s information or all eight in the display, and a single controller when moved, or the complete control surface’s assignments. Nice touch.

The display is 4.3 inches, 480 x 272 pixels, and seemingly full-color. It’s sharp and easy to read, with vivid colors. Information is presented clearly; there aren’t many graphics but they’re tastefully used when needed (see Figure 1 at left). Below the display are buttons F1–F 4, used to select parameters displayed above them in many of the screens. The K4 has a dedicated Transpose button, which acts globally on all setups in the unit (zones can be defined not to transpose if desired). It’s implemented nicely; press it once and it lights up and shows the current value on the display. Hold it and use the data entry controls to set a value.

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Five dedicated sequencer transport controls support MIDI Machine Control or CC messages, though there’s no word yet about Mackie Control or DAW templates. The only thing missing are drum pads of some sort. While there is certainly room on the K4 they would only add to the already considerable cost.

The Rear Panel: Connections for Days

Two five-pin MIDI inputs and a whopping eight outputs will be cheered by those who have a lot of MIDI hardware. The USB type B port connects to your computer; we were surprised that it provides only one virtual MIDI port, i.e., 16 channels. That’s not much for computer musicians, and is the only under-spec’d part of the design. Viscount is working on a software revision to expand that to eight virtual outputs (128 channels) and two inputs—that’s more like it. Four USB host ports (the rectangular type A) connect devices to the keyboard itself (drum pads, X/Y, or ribbon controllers) and can speak to other hardware sound sources. Each of the eight pedal inputs (!) can sense polarity and support both switches and continuous pedals. Pianists will appreciate being able to replicate full three-pedal control (not just for the optional internal sounds but for any expander or virtual instrument) and still have room for dedicated pedals for other purposes, such as volume and stepping through MIDI setups.

Taking Control

A complete setup of the instrument is called a Performance, and the K4/K5 offers 128 savable locations. If you work only with software and a USB controller you may find this new, as you likely do all your zoning and control assignments within your virtual instruments or host program (e.g.,Apple MainStage, Plogue Bidule, or Cantabile Performer). In those instances the computer is the “brain” while the controller is just hardware sending MIDI messages.

For working with hardware such as Receptors, sound modules, and MIDI-equipped analog synths (or a combination of that and a computer), though, the K4/K5 is quite the taskmaster, creating, storing, and recalling all the setup info. A Performance contains the definitions of up to eight key zones, four banks of controllers (knobs, sliders, and buttons), the wheels and pedals, and even custom input/output routings plus the ability to define MIDI messages that can set up your connected devices. Each Performance also contains four Scenes (parameter value snapshots containing everything I just mentioned) so you actually have 512 locations. The likely thought process is to use a Performance for a given song and the Scenes for sections of the song if needed; Scenes are labeled across the bottom of the display and recalled using the F1–F4 buttons. You can create custom chains of Performances, letting you configure set lists for your show easily.

A key zone can have one of four statuses: Disabled (not used), On (fully defined and active), Off (defined but not currently active), and Control (routes all controllers but not keyboard notes). A zone can be routed to any single physical output (or the internal sound board) and settings you can define per zone include bank and program change, various “mixing” settings, key shift, what type of MIDI message is output by aftertouch (nice!), aftertouch curve, and velocity curve (21 available, plus fixed and user-defined). You can define minimum and maximum values to create velocity splits, and invert the response for pseudo-crossfades. Of course you can define key range, and it’s nice to see that you can use direct key entry to set that up. I wish you could enter the velocity values from the keys as well, but no luck.

The controllers can send the following types of messages: CC, NRPN or RPN, pitch-bend, program change, and channel pressure, and their range can be defined. Many hardware synths (like Dave Smith’s products) and software applications use NRPN (non-registered parameter) messages, since these offer greater resolution (14-bit, 16,384 values) than a MIDI CC message (7-bit, 128 values). You can invert these values to set up organ drawbars or messages that move in opposite directions (great for volume, pan, dual filter sweeps and such), and scale minimum and maximum values for each physical controller—which you’d do to, say, limit a filter sweep to a musically desired range.

Buttons can behave as on/off, toggle, or stepped controls, and can also even send notes. Every controller setting can be named for clear feedback from the display (see Figure 2 at left). Pedals sport the same capabilities, with switch pedals able to step through Performances and Scenes, not to mention control the sequencer transport. You can create setup messages for a device (perhaps to change from single to multi mode, or to configure effects routings) and these can be any type of message, from CC to sys-ex. Plus you can determine whether it gets sent out just before the Performance change or after it.

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Surprising Depth

This is powerful stuff, and every time I tried to do something I found the K4 was up to the task. Want a given control to send more than one message? Create a second Zone set to Control and you’re there. Want to reuse an assignment from another Performance? A robust Copy mechanism copies anything from one controller/zone to a whole group of them, or a custom setup message between performances. Want to see Programs by the names your external devices use? The K4/K5 lets you create ten “Virtual Instruments,” each of which get a name, program/bank tables, and even custom names for their CC and NRPN messages. At first I thought you’d need to do all this data entry yourself, but I found that these files can be saved and loaded, and the unit comes with a selection of hardware instruments already defined. Yes, Viscount needs to support even more, but the framework is in place.

With so much user-naming possible, using the letters on the numeric keypad to enter names in “old-school texting” fashion made me wish for support for a USB QWERTY keyboard. Viscount says this is on the list for a future update.

Sound Expansion

You can add a sound board to the K4/K5, or purchase an EX model with the expansion already inside. This powerful DSP engine produces physical models of acoustic piano, Rhodes, Wurly, Clavinet, Pianet, and mallets, as well as additional sample-based sounds such as organ, bass, guitar, strings, and synths. It’s a mixed bag: I liked a lot of the electric pianos, and the parameters provide a good deal of sonic flexibility. Moving the pickup position on the Rhodes perfectly mimicked how one would “voice” the instrument, and being able to change the size of the tone bar, the Wurly hammer, and so on let me create a wide range of sounds. The Clav provides all the rocker switch settings of the original, with variable hammer “aging,” and the Pianet was spot-on. A selection of preamp, amp, and speaker simulations as well as modulation, delay, and reverb are included.

Less successful to my ears was the acoustic piano. It’s an incredible feat of engineering to create a piano sound solely using computer code and no samples, and the Physis certainly comes close. Being able to manipulate the hammer hardness and impact force was fun—sampling doesn’t let you dig into the virtual physics of the instrument like this. I was able to get a wider range of piano sounds than any multisampled piano could be tweaked to produce. That said, every sound I played and edited would have good characteristics but then some range of notes that had imperfections: a boxy quality or metallic artifact that I couldn’t dial out, for example. The available settings are actually macros controlling many more hidden parameters, which meant I couldn’t edit precisely enough to get the sound exactly to my liking. Viscount tells us a software editor that allows much finer editing on a note-by-note basis (think Roland V-Piano) will soon be available. Overall, the acoustic piano sounds would work fine in a louder band, certainly cutting through the mix. They’re less suitable for critical listening of exposed piano passages.

Don’t get me wrong. Viscount’s modeling engine is good and in time might be great. I’d use the Rhodes, Wurly, and Clav sounds on a gig without hesitation. Most of the sampled sounds also worked well, with the acoustic bass as a standout. But if it’s a stellar acoustic piano sound you’re after, currently you’re better off using the K4/K5 to control a software instrument like Synthogy Ivory or—if you want the flexibility of physical modeling—Modartt Pianoteq 5.


The K4/K5 is a monster controller keyboard, and should be on the short list for anyone looking for a high-quality weighted action unit for more advanced needs. It costs pro dollars, but you’re getting über-pro features. There are some very fine 88-key controllers from Akai, Arturia, and Roland that cost under $1,000, but they offer less in terms of zones, MIDI I/O, wheels, and pedal inputs. Only you can know whether you need the extra capabilities.

If you only need to work with a computer and plug-ins, the K4/K5 is surely overkill—and some of the other products mentioned are more computer-centric, with advanced preset management and control of your software. But for the musician with a mix of hardware and software looking for more of everything, there has been a lack of well-spec’d, great-feeling, weighted-action master keyboards in the last decade. The Physis K4 and K5 are a welcome end to that drought. I’m obviously less enthused about the $1,000 sound add-on given that there are excellent software instruments for much less—and again, anyone looking at the K4/K5 likely has a lot of hardware they’re looking to tame. I congratulate Viscount for coming this far and hope they’ll continue development and voicing to bring their freshman effort further along in the coming years. The potential is there.