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Terratec Komplexer VST

Wavetable Soft Synth [Windows] By Alan Tubbs
Published November 2006

Everything but the editing, Ma'am. The Keyboard window is much smaller than the others, but just right for finding sounds with the browser, trying them with the keyboard and testing how the Macro knobs affect the sound.Everything but the editing, Ma'am. The Keyboard window is much smaller than the others, but just right for finding sounds with the browser, trying them with the keyboard and testing how the Macro knobs affect the sound.

Terratec are a German company known primarily for their audio interfaces. One of their more intriguing products was a soundcard with the guts of a Waldorf Microwave on board. Terratec Producer, their pro music division, continue the Teutonic cloning with Komplexer VST, a soft-synth version of the Waldorf Micro Q wavetable synth. While not an exact copy of the hardware synth, it is close enough that it will load in voice information and make a good stab at replicating it. There are a few differences, but the wavetables are identical except that Komplexer uses resynthesis to round off the transitions between the samples rather than discretely stepping between them.

Komplexer comes on a CD with manual, service and registration cards in the box. The registration card includes the serial number. The installation process is as simple as loading in the CD, following directions and typing in the serial number. Be sure to check the Terratec site, as there was already a 1.01 version available while I was writing the review, and since this is a completely new synth, no doubt more fixes will be coming down the electron pike.

Terratec intend Komplexer to be part of a system which includes the soft synth, a keyboard controller and an optional wavetable soundcard. The Area 61 controller and card have been announced, and release is scheduled for next year. The entire system will allow you to design and assign controllers on your computer and then offload the CPU cycles to the keyboard with soundcard. Area 61 includes eight knobs which map to the on-screen macro controller knobs in Komplexer. Even in this era of ever-growing processing power, offloading CPU-intensive software is always welcome, as well as integrated control.

Catch The Wave

Waldorf's synths, and PPG's before them (like Ensoniq's 'transwave synthesis' or Sequential/Korg's wave sequencing), used playback of a series of discrete samples, called wavetables, as a sound source for the oscillator. Usually the synth provides control of the start point within the wavetable and the speed and direction of playback, as well as the ability to modulate these parameters with envelopes, LFOs and so on. This modulation changes the actual timbre of the oscillator — much like pulse-width modulation, although the discrete samples can be totally different. (Komplexer 's wavetables include square and pulse waves, so it can also do more traditional pulse-width modulation.)

Wavetable synthesis remains one of the more under-utilised methods of synthesis. The technique doesn't make for realistic sounds (how does that tuba turning into a trumpet work for you, Herr Conductor?), which is one reason why it is beloved by electronic musicians. It can be so... unnatural. Like other wavetable synths, Komplexer excels at unnatural sounds. I didn't have a Micro Q available, but I do have a Fizmo, which is Ensoniq's last wavetable synth. Though different, they share eerie similarities, much like analogue or S&S synths as a class. One of these similarities is that each synth consists of four layers, or complete voices. You work on one of the four at a time.

Komplexer has a number of windows, and opens up showing the last window used, but we'll start with the Keyboard window. This performance window includes an on-screen keyboard, naturally, as well as an abbreviated header, a file browser and eight 'macro' knobs. This is the window you would normally want in your host to pick a preset sound and test out the knob settings. The file browser also includes a File menu for loading and saving banks, wavetables and Micro Q settings. In stand-alone mode, there is also a normal Windows header, too, to replace the host's macro function. In your DAW, Komplexer 's header includes buttons for the other windows as well as for the four Layers. If you left/right-click on the logo along the bottom you get the credits and the Options page. The options include Bass Boost, which is switched on by default, Stereo, which mixes all the Layer outputs to the first stereo output, Number of Voices, and a Fixed Window Size. This last overcomes the problem some hosts have with a single plug-in utilising different window sizes; Komplexer 's other screens are much bigger, taking up most of the real estate on one of my monitors, so the smaller Keyboard window is practically required for working with a DAW.

Main Lines

The Main window is where most of the editing is done. The top third contains the three Oscillators. One and two are the same, while Oscillator three is less full-featured. All three share Octave tuning knobs and easy-to-understand Bend range, Keytrack, FM (Frequency Modulation) and PW (pulse-width) sliders. These make it simple to see the amount added or subtracted, since they look like audio meters and have a numerical readout above. Clicking on the slider bar jumps the change, while holding the right button lets you slide the amount. Keytrack is definitely fun to play with; its usual purpose would be to disconnect the keyboard pitch control altogether for percussion sounds, but odd tunings and reverse tunings are also available. It can be disconcerting to hear the pitch get lower the higher up the keyboard you play.

Most editing is done in the Main window. At the top right is MIDI Assign along with short hints, which change depending upon where the mouse cursor stops. Excellent, though it hardly makes up for the lack of a help button.Most editing is done in the Main window. At the top right is MIDI Assign along with short hints, which change depending upon where the mouse cursor stops. Excellent, though it hardly makes up for the lack of a help button.Oscillators one and two have wavetable buttons on their menus besides the usual pulse, saw, sine and triangle waveshapes used in subtractive synthesis. In the wave window you can see the shape(s). Both the wavetables and pulse options let you sweep through the sound file manually, or using controllers applied from a drop-down menu. There are 40 different sources available. The wavetables themselves are based on resynthesis, rather than straight wavetables, which is the reason transitions are so smooth. There should be more wavetables coming, and Terratec are developing a means to make your own. Creating your own wavetables promises to provide hours of sound-design fun, not to mention actual playing.

The static waves and pulse are good for analogue-sounding creations. Frequency modulation is not the DX variety, but allows for sound sculpting the old-fashioned, analogue way. Vibrato, of course, results when you use an LFO as a source, with more clangorous sounds when you use a modulator in the audible range. Sources can include any of the oscillators, one of the three LFOs or four envelopes, or noise. Oscillator three lacks the wavetable option but does feature a sync button (to oscillator two) for more old-time analogue fun. The other missing feature in oscillator three is the sub-oscillator that can add a square wave below either of the main oscillators.

Fun With Filters

The rest of the Main window resembles an analogue synth front panel. The oscillators are followed by a mixer, filters, an LFO and envelope section and some master controls. The mixer adjusts the volume of each oscillator; this is handy, since turning the oscillators off at source means they can't act as modulators. The Route knob below each sound source directs the sound through the filters; at its extremes, that source feeds one of the two filters only, while intermediate settings offer a balance. You can also choose to place the filters in parallel or serial mode. Ringmod combines oscillators one and two in the typically analogue fashion, while Noise can be added and changed from brown to pink to white with the Colour pot.

The filters look like standard fare until you crank up the resonance, whereupon they feed back on themselves even with no signal running through them. Kudos for Terratec for another analogue touch. With key-tracking, you can make all sorts of whistling-past-the-graveyard sounds, and with envelopes and cutoff modulation, you can revisit the space sounds from your favourite '70s science fiction soundtrack. There are 10 different filter algorithms and most feed back, except for the comb filters. I'll take it, since none of the other filters in my digital arsenal do this trick. Level controls the filter's output downstream of the distortion unit and Drive controls the level to the distortion unit. Each filter output can go into a different kind of drive, if you wish.

The Matrix window is pretty much self-explanatory except for knob assignments. You can make half-moon Pacmans with Range sliders as well interesting etch-a-sketch lines with the Value knobs. Notice the Macro knob description in the header.The Matrix window is pretty much self-explanatory except for knob assignments. You can make half-moon Pacmans with Range sliders as well interesting etch-a-sketch lines with the Value knobs. Notice the Macro knob description in the header.It is quite ergonomic to have the LFO speeds on the Main window, since that is the feature you'll be reaching for most of the time, and modulation depth is already controlled there in the Oscillator/Filter section. ADSR envelopes for Filter and Amplitude are also appreciated here. More in-depth control for each is available on the ENV/LFO window, but this makes for quick and dirty programming. The ENV/LFO window adds a second Decay and Sustain to the envelopes, as well as Trigger and Loop modes. The LFO section allows you to choose the waveform shape, with Snc and Clock buttons to control the phase of LFO start and other functions, and adds Keytrack, Delay and Fade controls. LFO3 also includes Step Shape, which, when sync'ed with the clock, can accent the beat of whatever it is assigned to.

Back in the Main window, we have Glide Time, along with a stair-step switch. I was hoping the stair stepping would reproduce that effect from the early days of computer-controlled oscillators where resolution was so bad that glissando could become a random, stair-stepping series of notes. However, here it merely sweeps up and down the keyboard automatically, almost like arpeggiation — not what I was hoping for, but a useful tool nevertheless. There is also a Poly/Mon switch, along with Unison, which adds up to six voices to a single oscillator, along with Detune and Spread controls. This is always a useful to fatten up some faux analogue. Finally, there are buttons to send the finished sound to the Arpeggiator and one or both of the effects engines. FX2 is global, while FX1 is per Layer. On the ARP/FX window you can pick Chorus, Flanger, Phaser and Drive for Effect 1, and control the amount, Speed, Depth and Delay time. Effect 2 adds Delay and Reverb to the choices, along with program-dependent knobs like Feedback or Predelay.

Matrix Revolutions

If the Main window is where most programming takes place, the Matrix comes in a close second. At the top are 16 slots for the modulation matrix. Along the bottom stretches the programming for the Macro knobs. And squeezed into the top right is the Arithmetic section. This section is useful, but complex (or maybe just unusual). It allows you to specify various operations like add, subtract, logical And and logical Or, along with A and B Operands to which these operations will apply. Each Operand has a choice of 40 sources, from Off to LFO1 and even itself. One uses these logical operations to perform simple or more complex tricks. The one example given in the manual is inverting an LFO waveform, and you can always dissect presets to figure out more. Then you can use an Arithmetic as a source in the modulation matrix.

The same 40 sources are also available in the 16-slot matrix, and can be sent to over 50 destinations, including the usual oscillator and filter controls and less obvious things like LFO speeds and sub-oscillator controls. If that isn't enough, you can assign the 40 sources, the modulation amounts and the effects parameters — just about everything for which there is an on-screen control — to the Macro knobs. The Macro knobs can control four parameters at once, with each parameter having its own maximum and minimum range and Max and Min value, as shown by a Pacman-ype icon. The Pacman shows where on the knob the effect kicks in and out, while the graph next to it plots both range and value. Thus, you can control the amount of filter cutoff while restricting the range of the filter resonance, saving your speakers a re-coning job. Or you could constrain vibrato within certain frequencies. You can also program the knobs to affect any Layer in a patch, or all of them at once. Most of the knobs already have some pre-programming on them, but you can add or change it to suit yourself. Finally, there is a MIDI learn function for every knob (every one I tested, anyway) to put all this power at your fingertips.

The last window is for the ARP/FX. The Arpeggiator is pretty standard, though feature-packed. There are 16 preset patterns, one user pattern and off — more than enough to get complex rhythms going out of this little unit.

System Requirements

  • Windows 98SE or later.
  • 1GHz Pentium III processor or better.
  • 512MB RAM.

Kompleting The Picture

Before I get too carried away singing the praises of Komplexer, I should mention I did have a significant problem with it. When I tried programming in the Main window, my music computer turned to molasses. Both mouse movement and playback were glitchy whenever I played a note, and CPU use jumped to 100 percent. None of the other windows exhibited this problem, so it didn't render the synth useless, just frustrating to program. Emails to tech support couldn't replicate the problem or provide an answer before Sound On Sound went to print. However, on my older and slower home computer Komplexer ran fine, so I think the problem probably lies with my cheap PCI double-headed video card. (The home computer has the expensive double-headed video card, since my latest and greatest music computer doesn't have an AGP slot.)

The good news is that I plan on finding a solution, since this synth will get a lot of use. The 128 presets are very odd or analogue-ish. There are a lot of basses, some pads and others that are downright strange. Even the pitch and modulation wheels march to the beat of a different programmer, starting from preset number 1. 'Incubator' is a paddish drone I immediately marked for use. When I started using it with a short riff, I discovered that the pitch-bend wheel did two different things — neither of them bending the pitch. Instead, the pitch wheel was assigned to the two Arithmetics and the modulation matrix. Pitch the wheel up and the pulse width changed; pitch the wheel down and the noise level came up. The PW effect wasn't a subtle one, but the noise made for a completely different sound. That is just a taste of all the routing one can do without much effort.

Leaving aside the weirdness emanating from its wavetables, Komplexer VST makes some of the best analogue sounds I've heard come out of a computer. If you like keyboard sounds from the '70s and '80s, before Sample & Synthesis came to rule the world, this synth will put you on the path to righteousness. Which is ironic, considering wavetables were one of the earliest forms of digital synthesis. Henry Ford told his customers they could have a Model T in any colour, as long as it was black. Komplexer has analogue and digital sounds covered, as long as you want them to sound electronic. 


  • An excellent implementation of wavetable synthesis.
  • Both the basic engine and the presets sound good.
  • Deep-level programming is available if you want it.
  • Should be part of a well-thought out system.


  • The rest of the well-thought out system isn't here yet.
  • Mac support isn't here yet.
  • Problems with editing and playing on one of the review computers.


£154.99 including VAT.

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