The Hardware Controller RoundUp: How To Get Physical With Your Recordings

Until digital recording appeared, every function in analog gear had an associated control: Whether you were tweaking levels, changing the amount of EQ gain, or switching a channel to a particular bus, a physical device controlled that function.
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Until digital recording appeared, every function in analog gear had an associated control: Whether you were tweaking levels, changing the amount of EQ gain, or switching a channel to a particular bus, a physical device controlled that function.

Until digital recording appeared, every function in analog gear had an associated control: Whether you were tweaking levels, changing the amount of EQ gain, or switching a channel to a particular bus, a physical device controlled that function.

Digital technology changed that, because functions were no longer tied to physical circuits, but virtualized as a string of numbers. This gave several advantages: Controls are more expensive than numbers, so virtualizing multiple parameters and controlling them with fewer controls lowered costs. Virtualizatoin also saved space, because mixers no longer had to have one control per function; they could use a small collection of channel strips—say, eight—that could bank-switch to control eight channels at a time.

But you don’t get something for nothing, and virtualization broke the physical connection between gear and the person operating the gear. People debate the importance of that physical connection; to me, though, there’s no question that having a direct, physical link between a sound you’re trying to create and the method of creating that sound is vital—for several reasons.


If you’re a guitar player, here’s a test: Quick—play an A#7 chord. Okay, now list the notes that make up the chord, lowest pitch to highest.

Chances are you grabbed the A#7 instantly, because your fingers— your “muscle memory”—knew exactly where to go. But you probably had to think, even if only for a second, to name all the notes making up the chord.

Muscle memory is like the DMA (Direct Memory Access) process in computers, where an operation can pull data directly from memory without having to go through the CPU. This saves time, and lets the CPU concentrate on other tasks where it truly is needed. So it is with controllers: When you learn one well enough so that your fingers know where to go and you don’t have to parse a screen, look for a particular control, click it with your mouse, then adjust it, the recording process becomes faster and more efficient.


Would you rather hit a physical button labeled “Record” when it was time to record, or hold down Ctrl-Alt-Spacebar and then type “R”? Yeah, I thought so.

The mouse/keyboard combination was never designed for recording music, but for data entry. For starters, the keyboard is switchesonly— no faders. The role of changing a value over a range falls to the mouse, but a mouse can do only one thing at a time—and when recording, you often want to do something like fade one instrument down while you fade up another.

Sure, there are workarounds: You can group channels and offset them, or set up one channel to increase while the other decreases, and bind them to a single mouse motion. But who wants to do that kind of housekeeping when you’re trying to be creative? Wouldn’t you rather just have a bunch of faders in front of you, and control the parameters directly?

Another important consideration is that your ears do not exist in a vacuum; people refer to how we hear as the “ear/brain combination,” and with good reason. Your brain needs to process whatever enters your ears, so the simple act of critical listening requires concentration. Do you really want to squander your brain’s resources trying to figure out workarounds to tasks that would be easy to do if you only had physical control? Trust me—you don’t. But. . . .


Some controllers try to squeeze too much functionality into too few controls, and you might actually be better off assigning lots of functions to keyboard shortcuts, learning those shortcuts, then using a mouse to change values. I once used a controller for editing synth parameters (the controller was not intended specifically for synths, which was part of the problem), and it was a nightmare: I’d have to remember that, say, pulse width resided somewhere on page 6, then remember which knob (which of course didn’t have a label) controlled that parameter. It was easier just to grab a parameter with a mouse, and tweak.

On the other hand, a system like Native Instruments’ Kore (covered in the 10/08 issue) is designed specifically for controlling plug-ins, and arranges parameters in a logical fashion. As a result, it’s always easy to find the most important parameters, like level or filter cutoff.


So do you just get a controller, plug it in, and attain instant software/hardware nirvana? No. You have to learn hardware controllers, or you’ll get few benefits.

If you haven’t been using a controller, you’ve probably developed certain physical moves that work for you. Once you start using a controller, those all go out the window, and you have to start from scratch. If you’re used to, say, hitting a spacebar to begin playback, it takes some mental acclimation to switch over to a dedicated transport control button. Which begs the question: So why use the transport control, anyway? Well, odds are the transport controls will have not just play but stop, record, rewind, etc. Once you become familiar with the layout, you’ll be able to bounce around from one transport function to another far more easily than you would with a QWERTY keyboard set up with keyboard shortcuts.

Think of a hardware controller as a musical instrument. Like an instrument, you need to build up some “muscle memory” before you can use it efficiently. I believe that the best way to learn a controller is to go “cold turkey”: Forget you have a mouse and QWERTY keyboard, and use the controller as often as possible. Over time, using it will become second nature, and you’ll wonder how you got along without it. But realistically, that process could take days or even months; think of spending this time as an investment that will pay off later.


There are not just many different controllers, but different controller product “families.” The following will help you sort out the options, and choose a controller that will aid your workflow rather than hinder it.

Custom controllers. These are designed to fit specific programs like a glove; examples include Digidesign’s C|24 and Command|8 for Pro Tools, Cakewalk/Roland’s Sonar V-Studio, Steinberg’s Cubase-friendly CC121 and MR816 CSX, WK Audio’s ID controller for Nuendo, and the like. The legends are program-specific, the knobs and switches have (hopefully) been laid out ergonomically, and the integration between hardware and software is as tight as Tower of Power’s rhythm section. If a control surface was made for a certain piece of software, it’s likely that will be the optimum hardware/ software combination.

General-purpose DAW controllers. While designed to be as general-purpose as possible, these usually include templates for specific programs. They typically include hardware functions that are assumed to be “givens,” like tape transport-style navigation controls, channel level faders, channel pan pots, solo and mute, etc. A controller with tons of knobs/switches and good templates can give very fluid operation. Good examples of this are HUI (an aging, but still relevant, control protocol used primarily with Pro Tools), the Mackie Control (which has become a standard—many programs are designed to work with a Mackie Control, and many hardware controllers can emulate the way a Mackie Control works), Euphonix Artist series controllers, Alesis Master- Control, M-Audio ProjectMix I/O (which supports both HUI and Mackie protocols, as does TASCAM’s FW- 1884), and TASCAM FW-1028. But there are also “single fader” hardware controllers (e.g., PreSonus FaderPort and Frontier Design Group AlphaTrack) which while compact and inexpensive, take care of many of the most important control functions you’ll use.

MIDI fader boxes. The late, great Peavey PC-1600 is a classic example of a MIDI fader box: It has 16 programmable faders and 16 buttons (there’s a data wheel too), which can transmit almost any kind of MIDI message. Similar controllers are made by Kenton (the USB Killamix has a joystick, nine knobs, and nine switches), Evolution (UC-33e), Behringer (the BCF2000, with moving faders, and BCR2000 with rotary controls are mainstays of many MIDIoriented studios), and CME—their Bitstream3X has a joystick, 35 knobs, eight sliders, 16 buttons, a ribbon controller, and tons of templates. While these don’t have the “fit like a glove” feature, the controls and switches are relatively easy to sort out, and you can generally create presets.

“Hybrid” mixers. These are often designed for DJ applications, but are applicable to any mixing scenario—they include both traditional mixing options and MIDI control. Korg’s Zero4 and Zero8 mixers are outstanding examples of the genre, as is Allen & Heath’s Xone:D series of products (particularly the Xone:D3 and Xone:D4).

Digital mixers. For recording, a digital mixer can make a great hands-on controller if both it and your audio interface have a multi-channel digital audio port (e.g., ADAT optical “light pipe”). You route signals out digitally from the DAW, into the mixer, then back into two DAW tracks for recording the stereo mix. Rather than using the digital mixer to control functions within the program, it actually replaces some of those functions (particularly panning, fader-riding, EQ, and channel dynamics). As a bonus, some digital mixers include a layer that converts the faders into MIDI controllers suitable for controlling virtual synths, effects boxes, etc.

Synthesizers/master keyboards. Some keyboards, like the Yamaha Motif XS and Korg M3, as well as master controllers from MAudio, Alesis, Novation, CME, and others build in control surface support. But even those without explicit control functions can sometimes serve as useful controllers, thanks to the wheels, data slider(s), footswitch, sustain switch, note number, and so on. As some sequencers allow controlling functions via MIDI notes, the keyboard can provide those while the knobs control parameters such as level, EQ, etc.

Really cheapo controllers. Remember that old drum machine sitting in the corner that hasn’t been used in the last decade? Dust it off, find out what MIDI notes the pads generate, and use those notes to control transport functions— maybe even arm record, or mute particular track(s). A drum machine can make a compact little remote if, for example, you like recording guitar far away from the computer monitor.

The “recession special” controller. Most programs offer a way to customize QWERTY keyboard commands, and some can even create macros. While these options aren’t as elegant as using dedicated hardware controllers, tying common functions to key commands can save time and improve work flow.

Overall, the hardware controllers designed for specific software programs will almost certainly be your best bet, followed by those with templates for your favorite software. But there are exceptions: While Yamaha’s Motif XS can’t compete with something like a Mackie Control, it is designed to serve as a custom controller for Cubase AI—which might be ideal if Cubase is your fave DAW.


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PRICE: $3,995
STRENGTHS: Integrates Sonar 8.0 tightly with a control surface, audio interface, and hardware synthesizer. ACT knobs provide soft synth and FX control. Surround and video control. Greatsounding audio I/O. Ten individual outputs are convenient for integrating external hardware. Mackie Control compatibility. Includes V-Link. Non-cramped layout. Very cost-effective, considering what the package includes.
LIMITATIONS: Takes up a fair amount of desktop space. LCD display is nothing special.

When Roland started working with Cakewalk, many predicted that Sonar would soon have a dedicated hardware controller. But the pair have taken it one step further: The latest Sonar software (8.0), when combined with the VS-700C control surface, VS-700R audio interface, and onboard Fantom VS synthesizer, creates a complete studio that Cakewalk/Roland call the “next generation” V-Studio.

VS-700C CONTROLLER While the VS-700C is optimized for Sonar, it’s also a Mackie-compatible controller that I’ve used successfully with Reason, Ableton Live, and other programs. This is a Big Deal, because the VS-700C isn’t tiny—you don’t want to need additional control surfaces.

The controller has five main areas: displays along the top, a “channel strip” section toward the center with nine 100mm motorized faders, an area to the right with jog-shuttle wheel/transport/surround panner/Tbar controller and loop/punch controls, and two sections toward the left. These include 12 knobs for EQ, sends, or “ACT” (more on this later), and an “access panel” with view, utility, and control keys. Of course we’re just talking broad strokes; there are also buttons for automation, different views, various select buttons, and the like.

The VS-700C could have been made smaller, but as designed, it has a spacious, open feel that doesn’t get in the way with serious projects. This aids workflow because you don’t have to parse the controls: The lettering is legible, and there’s enough space between controls that you needn’t concern yourself with being overly precise.

Superficially, the controller may not seem that innovative; it offers familiar hardware control for familiar software parameters. But, there are a few twists.

The most visually obvious is the Tbar controller, which provides front/rear balance for surround, an ACT control, or the ability to determine the transparency of X-Ray compatible plug-ins (the latter is a Sonar feature where you can make plug-ins less opaque so you can see what’s going on beneath them, or for that matter, make them disappear). While X-Ray isn’t quite like adding an extra monitor, it’s about as close as you can come in a software-only solution.

Another twist is having ACT control right on the control surface. The 12 ACT knobs let you control whatever soft synth or signal processor has the focus (assuming they expose VST automation), so you can move easily from controlling mixer faders to controlling filter, envelope, LFO, and other parameters. You can’t realize how useful this is until you actually try it.

The third surprise concerns the VS- 700R audio interface, so let’s investigate.

VS-700R AUDIO INTERFACE Just what the world needs . . . another audio interface, right? Well, in this case, yes. First off, it sounds great— Roland put some serious mojo into the mic pres. Second, it has lots of I/O: eight ins (XLR or 1/4" balanced/unbalanced), 10 separate 1/4" balanced/unbalanced outs, XLR main monitor outs, 1/4" balanced/unbalanced Sub out, and plenty of digital I/O—AES/EBU, S/PDIF, word clock, ADAT “light pipe,” and MIDI. There’s also a Fantom synth built inside the box, giving you a zerolatency hardware tone generator that takes the pressure off your CPU; and there’s a card slot for an optional ARX expansion board if you want extra synth power.

But what makes this special is the integration with the console. The mic pres are digitally-controlled, so you can control gain directly from the console, and save presets for the interface—very convenient when switching between sessions, where in one case you want the pres to work with vocals, and on another, to mic a drum set and guitar amp. And while the synthesizer is integrated with Sonar so it appears like a virtual instrument, you can also play it like a physical instrument. Furthermore, the console itself has a front panel line/guitar input with gain control, and two headphone outs.

USING THE V-STUDIO Although the unit being reviewed was a production prototype, glitches were not an issue and after a few days of testing, I started using it for mission-critical projects. That bodes well for what users can expect when everything is totally tweaked out, although it seemed like that point had already been reached.

The first thing I had to do was change around my (physical) desktop to accommodate the controller’s size. By raising the monitors about six inches, I had no problem fitting the console between a QWERTY keyboard and the monitors.

The controls are all obvious, but the most important “accessory” is the PDF list of commands. In addition to the toplevel controls, there are many supplementary functions you can access with Shift, Ctrl, Alt, and Command buttons. While logical, I recommend referring to the command list and committing the most important keystrokes to memory— it’s worth the effort.

Overall, there’s a big difference between using Sonar with “a bunch of other stuff” and using it as part of a tightly integrated system. For example, it may seem like a small thing, but being able to tweak the interface gain from the Console is a real time-saver. And while I’ve used control surfaces with Sonar, there was always a dichotomy between the moving fader device used for mixing, and a second control surface dedicated to ACT. Having them in one place—and being able to tweak EQ like a “real” mixer— makes for a truly comfortable working environment.

Bottom line: If you use Sonar on a professional basis, I predict that over the course of a year (or less) you’d easily save enough time for the V-Studio to more than pay for itself.


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PRICE: $349
STRENGTHS: Great variety of sounds with lots of presets. Tweakability is welcome. Sturdy, wellmade keyboard controller. Fast and fun.
LIMITATIONS: Much more limited editing options compared to using Arturia’s dedicated instrument software.

We covered using keyboard “workstations” like the Yamaha Motif XS and Korg M3 as control surfaces in last month’s issue (“Studio Meets Stage”). But Arturia’s Analog Factory Experience is something else: It mates VST/AU/RTAS virtual instrument software (with 3,500 sounds, useable stand-alone or as a plug-in) to a control surface designed specifically to tweak those sounds, thus restoring some of the “feel” of programming an analog synth.

As the controller is our main interest, we’ll breeze through the software. It’s version 2.0 of the original Analog Factory—essentially a “greatest hits” presets package from various Arturia soft synths: Moog Modular V, CS-80V, Minimoog V, ARP 2600 V, Prophet V/VS, and Jupiter-8V. Because there are so many presets, they’re organized in a browser format so you can specify attributes (for example, “Minimoog V synth bass sounds I use a lot”), and see a specific selection of patches.

The CME-made USB keyboard controller is sweet: 32 notes, wood end panels, physical MIDI output, and a solid feel. But the main feature is 11 knobs, four faders, pitch and mod wheels, and 11 switches. Controller settings are mirrored on-screen in the software, but with a difference: The knobs use the “add/subtract” method of changing data, while the sliders, which control envelope parameters, use the “match-then-change” protocol (see sidebar, “Reconciling Physical and Virtual Controls” below). When you call up a preset, the software shows the current slider parameter value as solid, and the physical slider position as “ghosted.” This makes it easy to see the difference between the two. With virtual knobs, a blue ring around the outside shows the current setting.

I find the knobs more convenient for “tweaking” sounds than for realtime live performance “fader slamming” and knob twisting; they’re fairly small and close together. However, I have used them for realtime control and as long as you don’t have to make lots of really fast movements, they work fine. If needed, you can tie the parameters to an external control surface.

The four sliders adjust envelope attack, decay, sustain, and release. Two knobs are dedicated to the crucial filter Cutoff and Resonance controls, and another two knobs control LFO Rate and Amount. Four additional “Key Parameter” knobs bring out what Arturia considers a preset’s four most important parameters, and put them under hands-on control. The remaining knobs affect level, Chorus amount, and (temposyncable) Delay amount.

The eight “snapshot” buttons seem more suited for live performance; you can save particular presets (edited or not), then recall them. These settings are saved on power-down. Remaining options include 1/4" connectors for Expression and Sustain pedals. What’s more, all the controls and switches produce MIDI control messages, so you can use them to tweak parameters in other software.

While the Analog Factory Experience’s goal is to put a lot of sounds and a keyboard at your fingertips for a low price, what sets it apart is being able to grab some knobs, make some tweaks, and modify a sound for your particular needs. Why sound like everyone else?


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PRICE: MC Mix $1,399.99; MC Control $1,999.99
STRENGTHS: Gorgeous, ergonomic industrial design. Compact. Very readable display. With supported applications, EuCon protocol gives better performance than MIDI.
LIMITATIONS: Mac only (no support for PC apps). Few applications have native EuCon support.

Euphonix created quite a stir when they went “downmarket” and introduced the Artist series controllers, and with good reason. We’ll concentrate on the MC Mix, then include a bit about the MC Control.

The MC Mix has eight 100mm faders, eight knobs, multiple buttons, and an OLED (Organic LED) readout that is bright, readable, and informative. What’s more, you can “stack” four MC Mix devices for 32 faders, and add the MC Control for another four faders—36 total. While the Artist Series does HUI and Mackie control emulation, it also offers the EuCon protocol, which is 250 times faster than MIDI and has eight times the resolution. Currently, only Apple Logic Pro, Steinberg Cubase and Nuendo, and Apogee Maestro (for Duet and Ensemble) support EuCon; MOTU’s Digital Performer and Apogee Maestro (for Symphony) are slated for future support. With HUI/Mackie control, the list expands to include Ableton Live, Apple Final Cut Pro and Soundtrack Pro, Digidesign Pro Tools, Propellerhead Reason, and MOTU Digital Performer.

A unique aspect of the Artist Series controllers is that while the main application installs on your Mac, you can control additional workstations by installing client software (EuCon Workstation) on other computers, and connecting everything via Ethernet. What’s more, the controller “knows” what protocol the application wants: For example, if you have Logic on one computer and Final Cut Pro on another, you can switch between applications and MC Mix will use EuCon for Logic, and Mackie Control emulation for Final Cut Pro.

My initial experience running Logic was positive: The faders snapped to attention, and all the controls worked in a fluid, obvious manner. I had less luck with Mackie emulation and Digital Performer, but Euphonix’s support (which is excellent, as is the documentation) recommended repairing the Mac OS X permissions . . . problem solved. And when I ran into a problem getting the EuCon Workstation software to work, they again provided a solution (that again involved something I had to do on the Mac).

The knobs and faders are touchsensitive, so the display jumps to what’s appropriate for what you’re touching—for example, touch the level fader, and a numeric value representing the slider setting replaces the track name. You can’t “fine-tune” the fader setting (e.g., by holding Shift while moving the fader), but the resolution is very fine anyway—for example, the fader value passes through eight discrete values while going from 0 to 1dB.

The only questionable aspect was moving ganged faders, as the ganged fader you’re not moving lags slightly. Also, a quick flick of one ganged fader will often cause the other to appear to “overshoot” before settling back to the correct position. However, any discrepancies don’t show up in the data stream they generate, so just consider the fader you’re moving of a ganged group as “the real thing.”

The MC Mix knobs have two main modes: Normal mode, where a knob affects the same parameter across multiple tracks, and Channel mode, where a knob affects multiple parameters within the same track. For example, when you punch the EQ button in channel mode, the leftmost channel in the display is the channel you’re affecting. But the knobs are a different matter: With Logic Pro, from left to right the eight knobs control Frequency and Gain for the four EQ stages. However, if you hit the Select button, the knob controlling Frequency now controls Q . . . and the On button underneath the stage control turns the stage on and off. Because we’re in Channel mode, all the knobs affect one channel. But remember that Logic Pro has eight stages of EQ: Just hit the Page button, and now the eight knobs control the high cut/low cut/high shelf/low shelf parameters.

So which is easier, using the screen, or using the knobs? For making a single, quick tweak, I’d go for the screen. But where the knobs come in very handy is if you’re working on a track and want to make a series of adjustments. In that case, you can keep your hands on the controller and move effortlessly among midrange, high end, low end, etc. What’s more, you can edit two parameters at once because you have two hands— twice as good as a mouse!

There are also some cool little touches; as one example, with parametric stages, the Freq knob does double-duty as the Q control (you alternate between the two by hitting the SEL button). The gain remains as a separate parameter on a separate knob. It makes sense that you’d choose the frequency, and then, decide on the amount of gain/Q at that frequency.

Regarding the MC Control control surface, while it has four motorized faders along with eight programmable knobs and 12 assignable buttons à la MC Mix, it also has transport controls, monitor/control room level controls, and a customizable 800 x 480 pixel touchscreen (very groovy). The MC Control is intended to serve as a control center for your DAW, as the touchscreen can access EQ and plug-in parameters, show metering, display track names, and the like; it’s also possible to set up macro commands to initiate command strings. Furthermore, the data entry wheel can provide zoom, jog, and shuttle, as well as edit parameters like trim, crossfade, and gain.

The expandable aspect of the Artist Series is noteworthy, as is the form factor: This is one controller that slides conveniently in between your QWERTY keyboard and monitors (or goes in front of the QWERTY keyboard). Overall, the Artist Series is a class act—as one would expect from Euphonix.


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PRICE: $199.99
STRENGTHS: Compact. Easy to use thanks to Automap Universal 2.0 protocol. Cool-looking semi-transparent GUI. Handles hosts as well as plug-ins. Very cost-effective.
LIMITATIONS: Doesn’t yet support Pro Tools on Windows (only on Mac), but support is imminent.

The USB-compatible Nocturn controller provides hands-on control for plug-ins (and mixing control for hosts); it offers eight touch-sensitive rotary encoders, a 45mm crossfader, eight buttons, and eight “function” buttons (e.g., select page, learn mode, select mixer mode, etc.). But it also has a ninth rotary encoder that controls whatever currently has the focus, as determined by your mouse. And . . . it’s cute and small, so you can almost certainly find a place for it on your desktop.

However, what separates Nocturn from the pack is the Automap Universal 2.0 software that ships with it. When you install the software (Mac OS X 10.4 or higher, Windows XP SP2 or 32/64-bit Vista), you’re presented with a list of plug-ins in your system (VST, AU, and TDM/RTAS) which you can then select to be “wrapped” so they operate with Nocturn. (I just selected everything—hey, why not?) A program considers these wrapped versions as separate plugins, so if your software scans plugins on start-up, you’ll see the Automapped versions being registered. Although Nocturn can’t wrap “keyed” plug-ins that work only with specific programs, as long as they accept MIDI control, you can treat Nocturn as a regular MIDI controller where you create your own mappings.

Once the software is installed and the hardware plugged into the USB bus, the fun begins. As soon as you open up a wrapped version of a plug-in, the Automap GUI shows up with a graphic of the available parameters (if necessary, there will be more than one page). You can determine the window’s transparency, encouraging you to keep it “on top” because you can see what’s going on with your host or plug-ins underneath—and the transparency helps a lot if you choose to resize the window to a large size, which can be very helpful if you’re running the remote at a distance from the computer. (You can also press a “view” button on the controller surface to hide or bring up the window.)

Nocturn is loaded with useful features, like being able to determine the encoder sensitivity and acceleration, as well as minimum and maximum control values. The controllers have a smooth, predictable action; being endless encoders, they use the “add/subtract” method of matching physical position to virtual control value. Also, doing MIDI control is a snap— very handy if the crossfader is unassigned, and you want to do a custom mapping. What’s more, there’s a browser that shows all open plug-ins and mixers, so if you have a really busy screen, you can call up the browser and go instantly to what you want to control. It’s really an extremely well-thoughtout package; sure, maybe you’d rather mix with faders than rotary knobs, but for plug-ins the knobs work just fine.

When I first checked out the Novation website while getting ready for the review unit to arrive, it all sounded too good to be true: It’s simple! It works with everything! It’s really inexpensive! It looks cool! You can mix with it! Well, this is one case where you can believe the hype. If you’re looking to get started with hands-on control, Nocturn is an excellent choice—and I could make a really strong case that it’s your best choice, especially when support for Pro Tools on Windows becomes available (which may already be available by the time you read this).


Most hardware control surfaces use MIDI as their control protocol. Controlling DAWs, soft synths, processors, etc. is very similar to the process of using automation in sequencing programs: In the studio, physical control motions are recorded as MIDI-based automation data, which upon playback, control mixer parameters, soft synths, and signal processors.
If you’re not familiar with continuous controller messages, they’re part of the MIDI spec and alter parameters that respond to continuous control (level, panning, EQ frequency, filter cutoff, etc.). Switch controller messages have two states, and cover functions like mute on/off.
There are 128 numbered controllers per MIDI channel. Some are recommended for specific functions (e.g., controller #7 affects master volume), while others are general-purpose controllers.

Controller data is quantized into 128 steps, which gives reasonably refined control for most parameters. But for something like a highly resonant filter, you might hear a distinct change as a parameter changes from one value to another. Some devices interpolate values for a smoother response.


With MIDI control, the process of assigning hardware controllers to software parameters is called mapping. There are four common methods:
“Transparent” mapping. This happens with controllers dedicated to specific programs or protocols: They’re already set up and ready to go, so you don’t have to do any mapping yourself.
Templates. This is the next easiest option. The software being controlled will have default controller settings (e.g., controller 7 affects volume, 10 controls panning, 72 edits filter cutoff, etc.), and loading a template into the hardware controller maps the controls to particular parameters.
MIDI learn. This is almost as easy, but requires some setup effort. At the software, you select a parameter and enable “MIDI learn” (typically by clicking on a knob or switch—ctrl-click on the Mac, right-click with Windows). Twiddle the knob you want to have control the parameter; the software recognizes what’s sent and maps it.
Fixed assignments. In this case, either the controller generates a fixed set of controllers, and you need to edit the target program to accept this particular set of controllers; or, the target software will have specific assignments it wants to see, and you need to program your controller to send these controllers.


With any controller that doesn’t use motorized faders, one of the big issues is punching in when a track already contains control data. If the physical position of the knob matches the value of the existing data, no problem: Punch in, grab the knob, and go.
But what happens if the parameter is set to its minimum value, and the knob controlling it is full up? There are several ways to handle this.
Instant jump. Turn the knob, and the parameter jumps immediately to the knob’s value. This can be disconcerting if there’s a sudden and unintended change—particularly live, where you don’t have a chance to re-do the take!
Match-then-change. Nothing happens when you change the physical knob until its value matches the existing parameter value. Once they match, the hardware control takes over. For example, suppose a parameter is at half its maximum value, but the knob controlling the parameter is set to minimum. As you turn up the knob, nothing happens until the knob matches the parameter value. Then as you continue to move the knob, the parameter value follows along. This provides a smooth transition, but there may be a lag between the time you start to change the knob and when it matches the parameter value.
Add/subtract. This technique requires continuous knobs (i.e., data encoder knobs that have no beginning or end, but rotate continuously). When you call up a preset, regardless of the knob position, turning it clockwise adds to the preset value, while turning it counter-clockwise subtracts from the value.
Motorized faders. This requires bi-directional communication between the control surface and software, as the faders move in response to existing automation values—so there’s always a correspondance between physical control settings and parameter values. This is great: Just grab the fader and punch. The transition will be both smooth and instantaneous.
Parameter nulling. This is becoming less common as motorized faders become more economical. With nulling, there are indicators (typically LEDs) that show whether a controller’s value is above or below the existing value. Once the indicators show that the values match (e.g., both LEDs light at the same time), punching in will give a smooth transition.