Review: Arturia Matrixbrute

LET’S HEAR THOSE VOICES

In essence, VCO 1 and 2 are two MiniBrutes, layered. These voices feature waveform mixing: providing a blend of Sawtooth (with Ultrasaw function), Pulse (with PWM ‘zero through’ sweet spot) and Triangle (with Metalizer wave modulation) waves. VCO 1 and 2 provide independent Sub oscillators with continuous adjustment between Sine and Pulse, however, unlike the MiniBrute, these are fixed to -1 octave. The tuning of VCO 1 and 2 is scaled exponentially and has a touch of drift. Thankfully, an auto-tune function is provided (press Panel and Kbd Track buttons together).

The more stable linear VCO 3 serves dual-purposes as either an audible VCO or as a third LFO. Waveform mixing and wave shaping options are absent, yet is does provide a sine wave, expanding upon the waveform selections found in VCO 1 and 2. VCO 3 also sports Clock divide settings and keyboard tracking of the pitch can be disabled.

Unusually, a noise source is provided with not just White noise, but also Pink, Red and Blue modes (each indicated with an appropriately coloured LED).

The Voice Modulation section of the synth is where you can achieve various FM, hard sync and audio-rate cross modulations between the oscillators with no less than four areas to explore. The first unipolar control adjusts VCO 1 modulation of VCO 2, the next three parameters are bipolar. VCO 1 or VCO 2 can be modulated by VCO 3. Exotically, VCF 1 or VCF 2 can also be modulated by VCO 3. Lastly, the noise source can modulate VCO 1 or VCF 1. A VCO Sync button provides hard sync of VCO 2 to VCO 1. With a bit of exploration, the sounds here cover everything from traditional hard sync sounds and basic FM tones through to chaotic noise and crunch. With extreme settings, you’ll coax random, mangled sounds more typical of modular synths.

The source mixer combines the VCOs, Noise and the External Audio input (available on the back panel) and controls how each source is routed to the VCF section. Each source can independently feed either the Ladder filter or Steiner-Parker filter or both filter types simultaneously. It’s at this point seasoned analogue synth heads will be salivating at the possibilities all this afffords… which leads me to the filter section. 

FILTER MY ENTHUSIASM

MatrixBrute sports both a Steiner filter and a Moog-inspired Ladder filter, configured either in parallel or series. Each provides controls for Drive, Cutoff, Resonance, Brute Factor (like the MiniBrute — effectively a variable feedback circuit), Envelope Mod amount and Output level. Both filters are multimode, with independent slopes (24dB or 12dB/octave), offering either Low Pass, Band Pass or High Pass modes. The Steiner filter also offers a Notch mode.

Unique to any non-modular analogue synth I’ve played is the ability to tweak two different filter cutoffs in an offset fashion via a dedicated endless encoder. This proved handy for discovering new sound textures by engaging different filter types, and routing different oscillators to the filters with independent drive and feedback stages. It’s interesting to note the filter resonances take on a varying character based on how much you drive the feeds from the mixer section — for more delicate tones, back off the levels in the mixer.

While on the topic of gain, it’s worth noting that there are four gain staging possibilities within MatrixBrute. Firstly, within the oscillators themselves (via adjustment of the waveform mixer), then the VCO mixer levels, the Drive and Brute Factor amount within the filters, and lastly, the Filters have independently adjustable output levels.

ASSIGN ME UP

Because this mono synth has a paraphonic VCO assign mode, it’s possible to play the three individual VCOs on different notes. That is, three-note chords on a mono synth. While not a unique concept, it’s implemented on the MatrixBrute in a clever and useful way.

In particular, a variation on the paraphonic mode comes in the form of Duo Split mode — the pair of Brute VCOs are routed through the Steiner filter from the ‘upper’ part of the keyboard split while a simple ‘lower’ patch is provided by routing VCO 3 through the Ladder filter. Usefully, if the arpeggiator is activated in this voice mode, only the lower sound is affected.

MODULATION SOURCES

MatrixBrute has three envelopes with a set of sliders dedicated to each. The first is hardwired to the VCFs, the second is hardwired to the VCA, while the third is freely assignable. ENV 1 and 2 have a slider adjacent governing how much note velocity will effect either the VCF or VCA, while ENV 3 has means to delay the onset of its attack stage.

Good things come in threes, and MatrixBrute also has a trifecta of LFOs. LFO 1 and 2 are fully-featured with seven wave shapes, syncable to clock, and have various retrigger modes. The phase of LFO 1 and the delay of onset of LFO 2 can be tweaked. While LFO rates can be increased to audio-rate frequencies, they don’t reach speeds as high as I’d hoped for. LFO 3 is provided via the ancillary function of VCO 3, covered earlier.

Adjacent to the Mod/Pitch wheels, you’ll find four white Macro Knobs. The mapping of each Macro Knob is defined within the modulation matrix, allowing each to modulate up to 16 destinations in either positive or negative amounts. While a preset designer offers ‘serving suggestion’ parameters to tweak for each patch, the Macro knobs put the means to create complex patch morphs within easy reach of the keyboard.

INTO THE MATRIX

Aside from its sound, the greatest highlight of MatrixBrute is the flexibility of its digital modulation matrix. Mod sources are listed on the left of the matrix as rows — these 16 sources are hard-wired. Mod destinations are presented in columns — the first 12 destinations are hard-wired while the last four are freely assignable to any knob-based parameter on the front panel. These last four assignable destination slots offer plenty of scope for creativity

Making an assignment is as simple as locating the appropriate button in the matrix and then specifying an amount with the Mod Amount encoder. Modulation sources can effect up to 16 destinations simultaneously (with independent amounts and polarity). Furthermore, the assignable destination slots can be used to scale one modulation assignment against another modulation source. For example, the amount of LFO modulation assigned to a filter cut-off can be modulated by one of the envelopes.

GLOBAL COMPUTER CONTROL

Since the MatrixBrute’s keyboard action is superior to its range of budget controllers, for the duration of the review I made it the master controller in my DAW rig. Naturally, this sent me on the hunt for the MIDI local on/off setting, which I couldn’t find on the front panel. After a little research I discovered it’s necessary to install Arturia’s MIDI Control Centre tool. Once installed, it recognised the synth via USB connection and traditional global settings such as MIDI local on/off, MIDI RX/TX channels and clock source were revealed. Library functions such as backing up the synth memories, naming patches and applying attribute tags are also found here. The software is also the only means of naming patches. It’s apparent that Arturia is banking on musicians having a computer on hand which might raise an eyebrow amongst the ‘hardware synth only’ brigade.

After power cycling, the MIDI local setting reverts back to Local On by default. This behaviour is by design, according to Arturia, however, having to set this parameter every time is an annoyance. A shortcut function to change this setting from the hardware is planned at some stage, however, I’d rather the choice be preserved in perpetuity.

STEPPING UP

The Step Sequencer provides 64 steps — each step having a note, accent, slide and modulation track. The output of the modulation track feeds the Seq Mod source in the modulation matrix (and thus can be assigned to up to 16 simultaneous destinations). Up to 256 sequences can be stored independently or attached to Preset memories using the Link function.

Creating a new step sequence is a simple matter. Press the Record button and start entering the notes in the order you wish them to play. To insert a rest, press the Tap tempo button. Press the Record button again once complete. If you wish to over-ride the number of steps in the sequence, press and hold the Seq Length button and press the appropriate step column in the grid. By hitting the Play button, the sequence will play at a static pitch. If you wish to transpose the step sequence up and down the keyboard in real time, simply play the keyboard. To edit the notes while playback has stopped, use the arrow keys. Editing notes while playback is engaged is achieve by ‘punching in’ using the Record and playing keys, however, I found the process to be quite imprecise.

While it’s exciting to have an integrated step sequencer I feel the physical user interface here could have offered a better means to edit sequences. Considering the vast grid of buttons on the unit, an Ableton Push-style presentation of steps would perhaps be superior, thanks to its generous array of 256 buttons (superior even to Push’s implementation with 64 buttons). I also find having only a single modulation track per sequence to be a puzzling limitation, especially considering the modulation matrix is digital. Furthermore, it would have been great to be able to set an independent length for the modulation track. Perhaps, these aspects could be addressed in future firmware updates.

HALLMARKS OF A HALL OF FAMER

The hallmarks of a great synthesizer are the degree of animation and spectral change you can get happening in the oscillator and filter sections, the versatility of the modulation matrix and the opportunities to create audio rate modulations.

The sound of this synthesizer is definitely going to appeal to those working in genres of electronica where a darker vibe is the order of the day. Paraphonic pads have a deliciously sour nature and due to having shared VCF/VCA stages, provide unusual articulations which inspire new ways of playing chord parts. With so many opportunities to introduce gain throughout the signal path, coaxing harder-edged sounds is a breeze, so much so, that finding the more delicate tone palette of this synth can be a touch challenging. Its dual-VCF structure is going to win over many musicians seeking a synth with powerful tone-shaping capabilities. If you’re seeking a synth capable of off-the-wall, raucous and rude tones, you’re going to love Matrix Brute.

With the proliferation of polyphonic analogue synths for around the same money or less than MatrixBrute (most notably, Novation’s Peak), expectations for a mono synth at this price point are high. This is where Arturia sets itself apart from the pack. MatrixBrute is an excellent synthesiser with plenty of hands-on control and is destined to be a highly sought after modern day classic.