Native Instruments Reaktor 2

For those with plenty of processor power to spare, the sky's the limit. This is Reaktor's MetaSynth — someone's dream design, complete with eight oscillators, four filters, four ADSR envelopes, reverb and echo.

With more and more software synths appearing for both Mac and PC, it takes something a little special to make people sit up and take notice. Martin Walker looks at a product that should do just that.

The design team at Native Instruments have certainly been busy since I reviewed their Generator 1.5 PC software synth back in the September '98 issue of SOS. This ambitious modular design allowed you to assemble up to 16 different instruments, each with up to 64 voices, and control them via MIDI. The sounds were created entirely by the software, using 32‑bit real‑time signal processing and sample rates from 22kHz to a rather academic 132kHz. Native Instruments have now updated Generator to version 2.0, and introduced two completely new products, Transformator and Reaktor — both also launched as version 2.0 to keep the product range in sync. And as if that wasn't enough, they've also ported all three to the Mac.

Transformator 2.0 is a stand‑alone program that provides sampling and granular synthesis with up to 16 instruments, each with up to 64 voices and controllable by MIDI. Reaktor 2.0, the program under review here, combines the features of both Generator and Transformator, giving a single application capable of both oscillator‑based synthesis, sampling and granular synthesis — a powerful combination indeed. Existing owners of Generator can upgrade to the new models as well.

Understanding The Ni User Interface

Version 2.0 of the NI applications have new streamlined Toolbars, and the Ensemble window features quick‑launch sub‑panels for its Instruments, as well as duplicating the most useful controls for quick access. You can also see here some of the new more general options such as the ADSR graphic displays, and the Oscilloscope for examining waveforms in more detail.

One of the beauties of the user interface that NI use across all their products is that you can work at various levels. At the heart of every design is a collection of Modules, which provide basic functions such as oscillators, filters, and amplifiers. These can be connected using virtual patch cords to build an instrument to any specification you like, as long as your computer is powerful enough to run it. This process is exactly the same as setting up a patch on a modular analogue synth, although NI go way beyond most hardware synths by providing several hundred Modules (there are 35 oscillators alone!). For those who want to create sounds that are a little different from the norm, there are also logic gates, slew limiters, parabolic shapers — even individual knobs, switches, faders and LED Modules are provided.

However, to prevent every user having to re‑invent the wheel, a separate selection of ready‑built Macros is also available. If, for instance, you wnt to use a Minimoog‑style oscillator that has switched triangle, variable pulse width, and sawtooth waveforms, along with Course and Fine pitch controls, you'll find that the Osc3wave Macro does just this, and will save you a huge amount of design time (it contains 12 Modules). Several hundred Macros are supplied in the library, including mixers, a choice of 17 envelope generators, step sequencers, microtonal scale tuning... the list goes on and on. Using a Macro also removes much of the donkey work involved in connecting more basic Modules, since all the boring bits such as attaching knobs or sliders to the Module terminals is also done for you (more on these controls in a moment).

When several Modules are connected together in a window on screen, they form a Structure. This concept can initially be confusing, since Macros also have their own Structures that can be opened in a further window, but as long as you remember that the Module is the simplest item on offer it becomes clearer. The Structure windows are where you connect everything together using virtual patch cords by dragging the mouse from one connection point to another on a different Module.

Once you have a completely functioning Structure of Modules or Macros (with suitable connections for MIDI control at one end and an audio output at the other) it becomes an Instrument, and gets its own front Panel. This is where the knobs, sliders, switches, and indicators appear, and you can drag and drop these in the Panel window as you wish to design your own graphic interface. By assigning controls to MIDI controller numbers, real‑time automation is also possible.

Each Instrument is self‑contained, but you can set up several Instruments for multitimbral operation in an Ensemble window — the highest level in the NI interface. Many ready‑to‑use Ensembles are supplied with each NI product, each one containing one or many Instruments with their own front Panels. Lots of ready‑built Instruments are provided as well, so that you can assemble your own Ensembles to suit a particular song.

This multi‑level approach can be confusing at first, but the beauty of it is that you can work on as shallow or deep a level as you wish. The casual user can simply control the many supplied Instruments and Ensembles from their Panels, while the dedicated synthesist can create new designs from the bottom up.

Common New Features

Reaktor sampling at its simplest. Diletant uses the new Sampler Module along with a single ADSR envelope generator to provide a multi‑sampled acoustic piano. Right‑clicking on the Sampler Module and selecting Properties launches the window shown in the right, where you can load and organise your multisamples.

NI have also improved the interface since I reviewed Generator, and all three version 2.0 programs have various new features in common. The most obvious is that the graphics have been streamlined and updated, losing the old 'watery two‑tone blue' look in favour of a much smarter green and black colour scheme with sharper controls (complete with drop shadows) that are much easier to read. Individual instruments in an Ensemble can now have their front panels launched by double‑clicking on their titlebar, and selected controls from each Instrument can now also be visible in the Ensemble window (see the top screenshot on page 110). This is perfect if you want to access a few controls from each instrument for real‑time tweaking, without having to obscure your screen with a huge front panel.

Gone also are the rows of control icons that used to appear across the top of each and every Panel, to be replaced by a much more elegant single Instrument Toolbar. This contains all the features of the old strips (and more!) and can either be docked at the top of the main window or left floating in another part of the screen.

This Instrument Toolbar shows the settings of the currently selected Panel, Ensemble, or Structure. You can either click on the relevant window elsewhere on the screen to select it, or select any window as an option fromhe drop‑down selection box on the Toolbar itself. Here you can launch the Panel or Structure for any window, Mute or Solo the selected instrument, select an existing Snapshot (patch), store, delete, or name a new one, and select the maximum number of simultaneous voices (up to 64), or add unison voices to fatten up the sound. The MIDI Learn button lets you assign a panel control to a MIDI controller, and the toolbar is completed with a MIDI activity indicator and selector for MIDI input channel. Several controls on this strip look identical, but you soon get used to what does what.

The Ensemble Toolbar provides more global options, such as the run/stop switch for audio processing, indicators showing current processor overhead, audio input and output levels, sample rate, and MIDI activity, and Stop, Start, and Master Tempo for the internal clock generator. This clock can be used with all Modules featuring Sync Clock and 1/96 Clock source Modules, or you can switch to External Sync to lock it to an incoming MIDI source.

Sampling The Options

Despite its comparatively simple front Panel and Structure, Formantor combines sample playback with granular synthesis and formant shifting, to provide an instrument that allows you to adjust playback pitch, duration, and gender separately. You can see the two main structures in more detail above.

The oscillator‑based virtual analogue features of Reaktor are the same as those in Generator, so readers interested in this aspect should look up my earlier review in SOS September '98: here, I'll concentrate on the exciting new features of its Transformator part, which include sampling, wave sequencing and granular synthesis. NI provide a 'Transformator‑Tour' folder containing 10 Ensembles specially designed to illustrate these new features. Each one either introduces a new Module or shows another facet of its use, which greatly helps in the learning process — all the following examples are taken from here.

The simplest new sample Module is Sampler. This provides polyphonic playback of one or more multisamples (mono only), and is used in the Diletant instrument, a basic velocity‑sensitive 10‑voice multisampled piano with ADSR envelope (see screenshot above). Double‑clicking on the Module opens up its Properties page, where you can set up multisamples across the MIDI keyboard. The samples are all loaded into RAM, either individually as WAV or AIFF files, or collectively in the form of a sample MAP file complete with split points.

Once loaded, samples can be played back in various ways, such as Forward and Backward, and with or without looping. Multisamples are a bit fiddly to set up (a keyboard graphic showing how the samples are mapped would help here) but no more so than on many hardware samplers. There are no sample‑editing facilities built into Reaktor, but selecting a sample and clicking on Edit will launch your choice of wave editor if you want to edit or tweak any loop points.

The Sampler FM Module is slightly more versatile, letting you control the starting point of the sample and add frequency modulation, but it's the Sampler Loop Module that really opens up the options; it offers far more control over loop start points and loop length, and plays both mono and stereo samples. This Module is used in the Simulant Ensemble, which illustrates some of the new possibilities, as well as adding a resonant filter, LFO, and pitch bend. You can map velocity to the start point of samples, and keyboard tracking can be either On (where, for instance, each note plays a different drum sound), or Off (when you alter the pitch of a single sound across the keyboard). When tracking is Off you can select the sound using the Shift control, or add velocity sensitivity, so that the choice of sound depends on how hard you hit the key.

FM And Wavesets

The Stimulant Ensemble is a more advanced version of Simulant, configured for monophonic use with portamento and extensive modulation control, but still using exactly the same Sampler Loop Module. This time, its frequency‑modulation input is connected to a further Sampler Module loaded with a single‑cycle sample of a sine wave, fed through a velocity‑controlled envelope section so that you can modulate the frequency of the samples in the Sampler Loop Module. The results of this degenerate rather easily into noise, but the Stimulant presets at least offer many expressive possibilities.

Vibrator once again has the Sampler Loop Module at its heart, but uses it in yet another way, by loading in WaveSet samples. These provide a similar method of synthesis to Wave Sequencing (as used in the Korg Wavestation) and Transwave synthesis (used in PPG Wave and Ensoniq synths), but shouldn't be confused with soundcard wavetable synthesis, which simply refers to playing back a set of waves from ROM chips.

Inside each WaveSet are up to 128 shorter waveforms; Wavelab showed that each WaveSet was 743mS long, with a filesize of 65K. However, the loop length is set to 6mS, and by moving this loop through the WaveSet you can sweep the harmonic structure of the resulting waveform in a host of ways, depending on how the WaveSet has been designed. There are 43 WaveSets on the Sample Library CD, and these are all simultaneously loaded into the Sampler Loop Module for easy access.

In Vibrator, you can choose your start position within the current WaveSet sample using the front‑panel Base control, and then modulate this position based on velocity and an ADSR envelope. The WaveSet control lets you choose different samples from the selection available. The results are wonderful — throaty leads, delicate scintillating swept harmonics, and ghostly voices in the machine. However, we're beginning to consume some serious processor power by this stage: a single voice took about 25 percent of the power of my Pentium II 300MHz processor when running at 44.1kHz. Overall, the Sampler Loop Module is certainly far more versatile than at first appears, and is at the heart of a huge variety of very different‑sounding Instruments and Ensembles.

Getting Grainy

The Resynth Module takes things even further by providing resynthesis (otherwise known as granular synthesis) options. Loading and mapping samples is done in exactly the same way as on the other sampler Modules, but during playback the Resynth Modue cuts up the sample into short lengths (NI call them 'particles') and then reassembles them. You can set the start point for playback, where the loop starts, and how long it lasts. The main difference between this and normal sample‑looping is apparently that the stream of short 'particles' are individually crossfaded to provide a smoother loop. To get the best loops, the Properties box marked Signal‑Informed Re‑Synthesis needs to be ticked, and the sample is then analysed for resynthesis. This can take some time, but only needs to be done once; the results are then stored along with the sound.

Looping is thus carried out automatically, which eliminates a chore. Although with very short particle lengths there is a rigid quality to the loop (as with all short loops), you can loosen this up by adding a little LFO. Apart from sine, triangle, and square waves, a random setting is also available, which can improve the lifeless sound of a short loop by giving it some slight variation in character.

There is a good example of this in the Plasma Ensemble, which provides several options to achieve a smooth loop with more difficult material, so that even if you only have a short sound, you can get a good result. The Re‑Synthesis section of the panel has a Freq control (which alters the grain length), and Random helps to break this up by adding some randomness to the proceedings. Smooth largely removes glitches between the grains, and Stereofy adds a random element to the stereo position to 'widen' the sound. All of these controls directly control some aspect of the Resynth Module.

The Pitch Former Module looks very similar to Resynth, but although only one of its terminals differs, it is capable of a very different range of sounds. Instead of the Gr (Grain Size) terminal of Resynth, Pitch Former has FS (Formant Shift), which lets you alter pitch, speed, and gender of your samples independently. Formantor (see screenshot, right) uses this to good effect with a speech sample of someone saying 'Transformator'. The included snapshots demonstrate the huge range of possibilities — you can start with any syllable, loop any selection, and change its apparent sex, to provide a huge range of bizarre sounds. This is definitely one for those into experimental sounds.

The Beat Loop Module is described as a 'real‑time resynthesizer for the synchronised playback of beat‑loop samples'. To illustrate the possibilities, two of these are used (along with two Sampler Loop Modules) to form the heart of the 4Dex ensemble. Deck 1 and Deck 2 play sampled loops using Beat Loop Modules, while Deck 3 and Deck 4 control triggered samples (in this case hi‑hat and bass drum sounds). The overall tempo is controlled from the central panel. The drum samples can be re‑pitched as required, and their individual beats set up in 16‑step switch matrixes. Each of the four Instruments can be dropped in and out of the overall mix using their Mute switches. So far, this is a fun real‑time performance tool. What makes it so exciting is that Deck 1 and Deck 2 also have independent control of pitch — you can change the key and everything still stays perfectly in sync, courtesy of the Beat Loop Module's real‑time resynthesis, and its ability to divide loops into multiple beats.

Summary

The six sampler Modules I've described — Sampler, SamplerFM, Sampler Loop, Resynth, Pitch Former, and Beat Loop — provide the bulk of the new features, but as we've seen, they can each be used in a variety of ways to give a huge range of sounds. Thirty Instruments using these are supplied to get you started, ranging from straightforward samplers to tempo stretchers and granular synths, and 200 Instruments are provided in total when you include the many other options based on analogue and FM synthesis.

Even then, these are only examples created using the supplied Modules and Macros. If you fancy adding another feature to an Instrument you can just open its Structure and patch one in, and of course more adventurous souls can design their own from scratch. This process is not for the faint‑hearted, and may require considerable time and patience. However, the potential really is endless as long as you have a fairly powerful computer (see the 'System Requirements' box).

Currently, you must run Reaktor as a stand‑alone application or from MIDI, but once the DirectX, VST 2.0 and ASIO support arrives the possibilities will open still further. If you have a soundcard with ASIO drivers you may then benefit from much lower latency, and with VST 2.0 support you will be able to add VST and DirectShow plug‑in effects to the sounds as well. I really am impressed with Reaktor, and at £249 it represents good value, especially since this also includes a sample library of over 500Mb — as long as you have lots of processing power and a suitable soundcard, go for it!