Review: Harrison Mixbus 3

Major Upgrade Adds MIDI Support, New Look, and More
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Plug-ins designed to imbue your music with the sound of analog are everywhere, but did you know there is an entire DAW built around that concept? The Harrison Mixbus 3, made by Harrison Consoles—a major manufacturer of large-format analog mixers—offers a complete production environment based around the analog mixer paradigm. In its latest incarnation, Mixbus adds important features such as MIDI and virtual instrument support, as well as an upgrade of its sound engine, a new look, and more.

Mixbus 3, which is based around open-source programming, supports AU plug-ins on the Mac, VST on Windows, and LV2 on Linux. It is very deep from a feature standpoint, but with the exception of its slick-looking Edit and Mixer windows, it’s not as graphically sophisticated as most major DAWs. Contextual edit and plug-in windows have a barebones look to them.


Mixbus 3 is designed to make your DAW mixer’s workflow feel more like that of a hardware console, while its Edit window features track lanes that will be instantly familiar to any DAW user. In addition to channel strips for individual audio and MIDI tracks, the mixer has eight builtin buses that are easy to configure (see Figure 1). Like a real analog mixer, each channel strip has its own compressor and EQ. Each of the buses and the master bus offer adjustable tape saturation called Drive. The master bus also has a built-in limiter.

The input channels feature standard bar graph meters, but the buses have VU-style meters to indicate the level of tape saturation. The master bus has its own tape saturation meter as well as a VU-like level meter. Sonically, the tape saturation in Mixbus 3 adds warmth that is both smooth and natural-sounding. It’s handy to be able to dial it in from a bus or the master bus.

The Compressor, which is available on the channel strips, buses and master bus, has been revamped to include a number of different modes. Leveler, which is the default, has a low, fixed ratio. It’s designed to help keep the track levels under control in a transparent fashion, and it works really well. I found it handy when mixing and used it liberally.

If you want to add heavier compression with more character, the Compressor mode is for you. It provides compression with a fixed attack and release, but an adjustable ratio. The third mode is Limiter, which gives you the heaviest compression of the three, and is designed for squashing down transient peaks such as those on a drum track.

The fourth compressor option is Sidechain, which lets you set the compressor to respond to Mixbus 3’s new Sidechain Bus. Each channel strip has a sidechain-send button, which makes configuring sidechain compression—something that can be confusing on some DAWs—really easy. The compressor is controlled with a Threshold slider, a parameter knob that differs depending on the Compressor mode set, and an LED-ladder-style gain-reduction meter. The EQ on each channel strip consists of a high-pass filter and 3-band semi-parametric operation. It lets you quickly sculpt the sound of each track without having to open a plug-in. The buses and the master bus all have a three-knob Tone section, providing some additional, although rather broad-brush, EQ options.

Although the end result may be the same, having the compressor and EQ right there and ready to go in each channel makes Mixbus 3’s channels feel more console-like in comparison to most DAW mixers, where you’d have to open a plug-in for those kinds of processing tasks.

Four of the eight buses are visible when you create a new session using Mixbus 3’s defaults, and the others can be easily opened. Signals can be routed from any input channel to any bus via individual bus on/off switches and volume knobs on each channel strip. You can turn off the channel’s master bus routing if you’re using the bus for a subgroup configuration rather than as an effects return.



If you used Mixbus 2, you’ll notice that the GUI has been redesigned for Mixbux 3. Following the latest trend in DAW design, the new look is dark and monochromatic. The graphics have been optimized for Retina Displays, where they look amazingly crisp.

My problem with the new design is that the channel EQ knobs are now smaller and harder to read than they were in Mixbus 2. What’s more, the Record buttons on each channel don’t get very bright when activated, making it harder than it should be to tell which ones are armed. (For obvious reasons, you don’t want to have any doubt about which channels are armed for recording.)

These problems can be alleviated to some extent by adjusting the theme colors and mixerstrip scale. Harrison’s developers say they are making some tweaks to accommodate different screen sizes and brightness. But as it stands now, the new look may be slicker, but it’s less user-friendly.


Also new in Mixbus 3 is 64-bit compatibility and a multicore engine, which allows for larger track and plug-in counts. Mixbus 3 also offers 32-bit floating-point operation, so as long as you record audio that’s below 0 dBfs, it’s not going to get clipped in the box, which is very helpful when dealing with gain-staging in a mix.

Previous versions of Mixbus required that you use the third-party utility called Jack to facilitate inter-application audio. That’s no longer the case, although Mixbus 3 is still “Jack-aware,” so you can still use Jack if you want to.


One of the factors that impeded Mixbus as a full-service DAW in the past was its lack of MIDI support. Happily, that’s no longer the case, as Mixbus 3 introduces MIDI recording and editing and virtual instrument support.

Fig. 2. Expanding a MIDI track vertically reveals a piano-roll-style editor. MIDI editing in Mixbus 3 takes place in the Edit window. There’s no need to open a separate editor. When you enlarge a MIDI track’s vertical size past a certain point, it turns into a pianoroll style editor (see Figure 2). You can move notes around, shorten and lengthen them, and change their velocity, among other editing functions. Increasing and decreasing velocity is most easily accomplished by way of your mouse’s scroll wheel.

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When you select a note and turn the scroll wheel, the velocity value of the note is shown in large letters next to it, and updates as you turn the wheel. If you don’t have a scroll wheel you can right-click to open a dialog box, and numerically enter velocity values, but it’s more cumbersome.

As an aside, I should mention that Harrison recommends a three-button mouse with a scroll wheel as the optimal pointing device for use with Mixbus 3. Many functions are accessed via right-clicks, and some with center-clicks that require the third button. (I got around just fine with a two-button mouse with a scroll wheel.)

Oddly, the program doesn’t support control-clicking as a substitute for right-clicking, which is pretty standard on Macs. As a result, I found myself a bit hindered when trying to control Mixbus 3 from the trackpad on my MacBook Pro. The trackpad’s preferences do let you select from a couple of different gestures to substitute for a right-click, but I didn’t find either as convenient as control-clicking would have been.


The MIDI implementation is easy to use once you get used to it: As with audio, editing options depend on which tool you’ve selected from the toolbar. Mixbus 3’s editing tools, like many aspects of its GUI, do not necessarily stick to standard DAW conventions. In some ways, this is useful, as it allows the developers more flexibility, but the downside is that some aspects of Mixbus are not particularly intuitive, due to their unfamiliar structure.

A good example of this is the Quantize function, for which Mixbus substitutes unusual nomenclature in the place of standard rhythmic values found in most quantize features. Some are pretty easy to decipher: Beats/8 is an eighthnote value, and Beats/16 is a sixteenth-note. But to figure out Beats/10, you have to stop and think, and possibly pull out a calculator. Mixbus 3 does let you quantize to some unusual values such as Markers, Region Starts and Ends, and CD Frames.

A large selection of MIDI plug-ins come with the program, typically offering a single function each, such as channel filtering, velocity randomization, and chord creation, among many others. As for virtual instrument support, Mixbus 3 allows you to open your VST (Windows) AU (Mac) or LV2 (Linux) instruments. I had no problems opening any of my AU instruments.

Fig. 3. Included with Mixbus 3 is setBfree Tone Wheel Organ. Mixbus 3 comes with two instruments of its own. Reasonable Synth is essentially a placeholder that appears by default in a newly created MIDI channel. It has no controls and only one sound. The other, setBfree DSP Tonewheel Organ (see Fig. 3), is a warmsounding and well-featured Hammond organ emulation. It sports virtual drawbars and a Leslie simulation, switchable Percussion, and Vibrato, Overdrive, and Reverb.

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That’s the extent of the included instruments. If this were a full-priced DAW I would complain about how few there are. However, considering Mixbus 3 costs $79, its lack of instruments is less of an issue, especially considering more people will use Mixbus 3 for audio recording and mixing rather than for MIDI production. That said, the lack of included plug-ins is more problematic when it comes to processors.



Other than what you get in the channel strip, Mixbus doesn’t give you any processor plugins. However, it does offer a bunch for sale from its online store. For example, you can buy the Harrison Plug-In Essentials bundle for $69, giving you the GVerb+ reverb and 3D Triple Delay. A number of other bundles and individual plug-ins are available; some cost more than Mixbus 3 itself.

Harrison also offers a plug-in membership plan called Plugged In, which costs $9 per month; the major attraction is a 50-percent discount on all the plug-ins and bundles in Harrison’s store.

According to the Mixbus 3 manual (which could stand to be significantly beefed up, content-wise), “You may still add plug-ins if you wish, but it is no longer necessary to purchase and choose between multiple plug-ins each time you want to change your sound. You can make a great mix without any plug-ins at all!” I must humbly beg to differ, as, with very few exceptions, most mixes require ambient effects, and probably parametric EQ at the very least, none of which comes with Mixbus 3. If you already have a plugin collection, then Mixbus 3’s lack thereof won’t be problematic for you. If not, expect to spend some additional funds, whether you get your plug-ins from Harrison or others.


Mixbus 3 is a worthy update thanks to new features like the revamped compressor section, with its multiple modes and sidechain support, the 64-bit engine, and 32-bit floating-point processing. With the addition of MIDI functionality—albeit somewhat limited—and virtual instrument support, Mixbus is now more of a full-fledged DAW. Now you can do soup-to- nuts projects in it, rather than just audio recording and mixing.

Considering its minimal cost, one could also use it simply as a mixing platform, importing stems (and MIDI files, if you want) into it from another DAW, and taking advantage of its excellent sound, tape saturation effects, and analog-style workflow.

My wish list for future versions would include better visibility of the EQ controls on the channel strip, a more thorough manual, inclusion of reverb and delay in the basic plug-in set, and perhaps more standardized nomenclature and structure for some of its features, in order to make it more intuitive.

Overall, Mixbus 3 improves what was already an intriguing product. It’s definitely worth a look, especially if you miss the workflow of a console-based studio.

Low price. Compressor and EQ on every track. Simulates analog-mixer workflow. Tape saturation. MIDI tracks and virtual instruments. 64-bit engine. 32-bit floating point processing. Buses assigned with a single click.

Lacks MIDI learn for external controllers. Expensive.

$79 Upgrade from previous versions: $40