The original Mackie HUI (Human User Interface) MIDI control surface debuted in 1997 and transformed mixing in Pro Tools by offering a physical interface
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The original Mackie HUI (Human User Interface) MIDI control surface debuted in 1997 and transformed mixing in Pro Tools by offering a physical interface with knobs, faders, and buttons that closely resembled their software counterparts.

Since that time, several moderately priced MIDI control surfaces with touch-sensitive motorized faders have arrived on the market. Many have adopted the HUI's MIDI protocol as a standard. With the release of the Baby HUI (see Fig. 1), Mackie has joined its competitors by offering a small-footprint device with many of the most common control-surface functions.

The Baby HUI's feature set is a subset of its big brother's, so any DAW that recognizes the original HUI will work with the Baby HUI. The current list of compatible DAWs includes Digidesign Pro Tools and MOTU Digital Performer on the Mac, Mackie Soundscape 32 and Mixtreme on the PC, and Steinberg Nuendo on both platforms.


I ran the Baby HUI through its paces with Pro Tools 5.1.1 and Digital Performer 2.72. In both environments, the Baby HUI behaved exactly as promised. Setup was effortless, and within minutes I was mixing away. The Baby HUI's fader motors are quiet and smooth, and the faders mimic on-screen fader movements perfectly. As with most touch-sensitive motorized control surfaces, the hardware faders respond best when your finger touches the top of the fader knob. Pushing the fader from below provides too little contact area between finger and fader and may not always register properly.

The Baby HUI's rear panel is sparse, consisting of MIDI In and Out jacks, a connector for the line-lump power adapter, and an On/Off switch (see Fig. 2). Installation and setup is as straight-ahead as it gets: connect the MIDI In and Out cables to your MIDI interface, turn on the Baby HUI, configure your interface software (such as OMS or FreeMIDI) and your DAW software to recognize the Baby HUI on the appropriate MIDI port, and you're in business.

At approximately 14 inches wide by 10 inches deep, it's possible to nestle the Baby HUI into virtually any desktop recording environment. By contrast, many more-sizable control surfaces, such as the original HUI and Digidesign's Control|24 and Pro Control, require that the studio be configured around them. Even some of the Baby HUI's more direct competitors, such as the Radikal SAC-2.2K, take up more workspace.


Like most MIDI control surfaces, the Baby HUI is divided into two areas: a Master section on the right and a Channel section with individual faders on the left. The simple, straightforward layout has relatively few controls, which makes the Baby HUI a friendly and incredibly easy device to learn.

Each of the eight identical channels has a 60 mm touch-sensitive fader. The faders have a nice feel and react instantly to the touch, although full-length 100 mm faders would have been better. Above the faders, the Mute and Solo buttons have red and yellow LEDs to indicate their status. Soloing a channel causes the Mute lights on the nonsoloed channels to blink red — that's a nice touch.

A green signal-level LED serves as a poor man's meter bridge, lighting up to indicate the presence of activity on each channel. A rotary encoder at the top of each channel functions as a pan control or as one of four send-level controls, depending on which assignment buttons are active in the Master section. No cool LEDs light up to indicate the rotary knob positions as on the big HUI, but pushing down on the rotary knob selects that channel as currently active. Holding the nearby Shift key and pressing the knob arms the channel for recording.


The Master section is divided into three subsections providing buttons for transport functions, automation, and encoder assignments. The Transport section has five large controls (Rewind, Fast Forward, Stop, Play, and Record) with built-in LEDs so you can easily see which transport mode you're in. Return-to-Zero and End buttons are just above the transport controls. Holding down the Shift key causes those buttons to double as Selection-In and -Out buttons. That's a good feature, but In and Out are common enough controls to merit their own buttons.

A pair of Bank Select buttons with a numeric LED screen indicate which bank of onscreen faders is currently controlled. Holding Shift while pressing the Bank Select buttons lets you move the Baby HUI's fader assignment a channel at a time, rather than in banks of eight.

The Automation section consists of ten buttons. The Transport, Mixer, Memory Location, and Edit buttons bring their respective software windows to the foreground on the computer. That's a terrific time-saver when working with limited screen space. The automation buttons work in tandem with the rotary encoder knobs to set the Automation mode for a given channel. Hold down one of the buttons: Bypass/Off, Read, Write, or Touch, then press the encoder knob to assign the mode for that channel. Automation latch mode is not supported. When you hold down the Shift key, each automation button selects a specific automation parameter (Volume, Mutes, Panning, and Send Levels) to enable or disable. That's another nifty and useful feature.

The Encoder Assignment section consists of five buttons that control Pan and four Send Level assignments. The Baby HUI's encoders are always in the same mode, so pressing the Pan button assigns all the encoders to control pan position.


With all of the Baby HUI's benefits, I still have some mixed feelings about the product. I'm a huge fan of MIDI control surfaces and applaud Mackie for making a small, easy-to-use affordable controller with motorized faders. But while I'm not expecting a Mercedes for the price of a Yugo, some of the features left out of the Baby HUI would have made it much more versatile.

Leaving out niceties such as a meter bridge, an analog monitoring section, 100 mm faders, a numeric keypad, and even a scrub wheel is understandable. But leaving out a 4-character LED display above each fader makes bank switching a confusing experience. Without the track names listed above the faders, you have to constantly refer back to the DAW's mixer screen to determine which tracks each fader controls. (According to Mackie, adding features such as 100 mm faders and 4-character LED labels would have raised the price of the Baby HUI significantly, making it less suitable for low-end systems like Digidesign's Digi 001.)

Leaving out Zoom buttons is another big oversight; I use the Zoom buttons on my big HUI all day long. But the biggest problem with the Baby HUI is that it doesn't let you address plug-ins. Having the ability to control four send levels is great, but my preference would have been to use that precious top-panel real estate to include plug-in control buttons, which are conspicuously absent. Indeed, there is enough empty space in the Master section that dedicated plug-in buttons could have been added without removing anything else.

In a way, Mackie's biggest competitor is itself. With a list price of $1,299, the Mackie Control is a far superior product to the Baby HUI and most other products in that price range. All of the features that I miss in the Baby HUI are provided in the Mackie Control, and though its footprint is bigger, it's still reasonably svelte. Unfortunately, the Mackie Control doesn't support Pro Tools at this time (although it does support most other sequencers and DAWs). However, Mackie has begun work on a HUI emulation mode for the Mackie Control that should be finished some time this year.


In the Baby HUI, Mackie has created a small, reasonably priced MIDI control surface that boasts many of the features found in larger, more expensive units. If you're ready to kick the mouse-mixing habit and you're a heavy Pro Tools user with a small workspace or a small budget, the Baby HUI can get you rolling in style. But if you have a bigger budget and a bigger studio, you might want to consider some of the Baby HUI's bigger brethren, especially the Mackie Control.

Nick Peckcreates sound for film and games and plays jazz on a 75-year-old piano with no MIDI port. E-mail him


Mackie Designs
Baby HUI
MIDI control surface


PROS: Small footprint. Easy to use. Affordable way to get started mixing in Pro Tools with motorized faders.

CONS: No Zoom buttons. No track-name LEDs. No plug-in control support.


Mackie Designs Inc.
tel. (800) 898-3211

Baby HUI Specifications

Number of Channels8Faders60 mm touch-sensitive, motorizedSends4Display2-digit LEDMIDI Ports(1) In, (1) OutPower7.5 VDC (line-lump external power supply)DAWs Currently SupportedMac: Digidesign Pro Tools, MOTU Digital Performer, Steinberg Nuendo PC: Mackie Mixtreme, Mackie Soundscape 32, Steinberg NuendoDimensions14.6" (W) × 3.4" (H) × 10.1" (D)Weight7.6 lb.