Virsyn Virsyn 1.1

Software-based VirSyn is a 12-part multitimbral modular synthesizer for Windows. Each Part consists of a 32-voice modular synthesizer with a step sequencer,

Software-based VirSyn is a 12-part multitimbral modular synthesizer for Windows. Each Part consists of a 32-voice modular synthesizer with a step sequencer, an arpeggiator, and insert effects. VirSyn offers global reverb and chorus effects, a song manager, and a 12-channel output mixer. You can control all parameters with MIDI, and a unique, eight-dimensional automation screen (with four x-y controllers) lets you control as many as 64 simultaneous parameters.

VirSyn is available as a VST Instrument plug-in ($149) or a standalone application, which includes the VST plug-in and a built-in WAV file recorder. The extensive MIDI and sequencing capabilities of the standalone version make it well suited to live performance. Both versions come with more than 800 factory programs in a broad range of categories. You can download a limited-time, save-disabled demo of VirSyn as well as MP3 audio examples at the company's Web site.

For copy protection, VirSyn uses a key-disk scheme with separate key disks for standalone and VST installations. The authorization process is straightforward, though some dialogs are in German, which might cause a few anxious moments. You can deauthorize the program if you want to move it to another computer. Emergency authorization disks are supplied as insurance against lost authorizations.

As with all software synthesizers, performance varies depending on your computer's processor speed, available RAM, MIDI and audio drivers, and audio hardware. VirSyn supports ASIO audio output and DirectSound. In the VST version, performance and some features also depend on the chosen VST host. I tested VirSyn on a Pentium III/700 MHz Dell laptop computer running Windows 98SE with a Tascam US-428 audio/MIDI USB interface. Under those conditions, sound quality was good and latency was low but still noticeable.


VirSyn uses a matrix modular format. Rather than cabling modules together in a graphical user interface, you connect the various components using context-sensitive menus for the inputs and outputs on each component's control panel. Because virtually any connection that makes sense is available, VirSyn lacks the limitations inherent in a system with a fixed array of modules. Although it doesn't offer the graphic feedback provided by a cabled system, VirSyn's format has a significant advantage in that the control panels are in the same positions regardless of the synthesis configuration.

It was difficult to trace VirSyn's signal and control paths initially, but once I learned where to look, I could quickly deconstruct and modify factory presets as well as build my own patches from scratch. One especially nice feature that makes programming VirSyn easier is that the controls do not move on any module that isn't being used.


VirSyn's sound sources include four analog-modeled oscillators, a subharmonic pulse-wave generator, and white and pink noise sources. Three oscillators offer 64 waveforms with Wave Modulation, which mixes a variable-phase copy of the waveform with itself. Wave Modulation lets you produce a limitless variety of new waveforms, and you can modulate the phase differential with any control source (such as an LFO or envelope). You can set the oscillators to run free, or you can reset to the waveform's beginning with each new note, which is important for producing uniform drum sounds. You can also turn keyboard tracking on or off independently for each oscillator.

Oscillators 2 and 3 can be hard-synced to Oscillator 1, and any audio source can frequency-modulate them. The fourth oscillator, Multi Osc, actually combines six detuned oscillators. With a little detuning modulation, you can quickly descend into the realm of truly clangorous timbres. The subharmonic pulse-wave generator produces variable-width pulse waves at Oscillator 1's first six subharmonics (the ratios of the subharmonics to Oscillator 1 are 1:1, 1:2, 1:3, 1:4, 1:5, and 1:6). Combine the subharmonic pulse-wave generator's signal with another oscillator tuned down three octaves for instant beef.


For signal processing, VirSyn provides four filters — two Multimode, one Formant, and one WaveDelay — together with ring-modulation and waveshaping modules. The Multimode filters come in 12, 18, and 24 dB-per-octave versions. They will resonate to the point of self-oscillation and produce a soft distortion when you push their input levels above 0 dB. Each Multimode filter is made up of several subfilters whose cutoff frequencies can be spread out using the Frequency-Shift (F-Shift) control, which slightly adjusts the slope or bandwidth of the filter, depending on its type. Controlling F-Shift with an envelope or LFO is similar to, but subtler than, controlling the filter's cutoff, and it quickly became one of my favorite VirSyn features.

The Formant filter is a three-filter parametric EQ that can be configured as three bandpass filters in parallel or three notch filters in series. The bands have independent resonance and relative level controls. In Bandpass mode, the Formant filter is useful for simulating vocal effects, especially when envelopes are assigned to modulate the band frequencies. In Notch mode, modulating the band frequencies with an LFO produces flanging and phasing effects.

WaveDelay, VirSyn's most unusual filter, is a feedback delay line with a pitch-synchronous delay time. You can vary its decay time from 50 ms to 200 seconds with the Feedback control in real time. WaveDelay has two inputs: one for the impulse that starts the WaveDelay feedback cycle and another for the signal to be fed back. Typically, the second input is assigned to WaveDelay's output, resulting in a standard feedback delay line. You can get interesting results by processing the output of the WaveDelay with, for example, one of the filters before feeding it back to the second input. You should protect your ears when you use WaveDelay; small changes in the settings can quickly produce uncontrolled feedback.

The remaining audio modules include an output amplifier, three insert effects, and a WaveMixer (a 5-channel submixer). The amplifier has built-in overdrive, downsampling, and bit reduction. The effects are overdrive (from hard clipping to soft distortion), delay/echo (a dual stereo delay with feedback), and modulation (chorus, flanger, and phaser). The WaveMixer is useful for submixing into the other modules as well as for the final mix (before the amplifier). Although WaveMixer provides three outputs (Mixer, Submix 1-3, and Submix 4-5), I would like to have had more submixing options.


VirSyn provides four envelope generators (EGs) and four LFOs. The EGs are DADSR (delay, attack, decay, sustain, and release) format, and all envelope parameters can be modulated. VirSyn provides three key-triggering modes (Normal, Reset, and Legato), and any LFO can trigger the envelopes. The LFOs offer sine, triangle, square, ramp-up, and ramp-down waveforms as well as sample-and-hold and random. In Sample-and-Hold mode, the LFO samples the output of one of the other LFOs, making it possible to build complex, repeating patterns quickly.

Twenty bipolar Modulation Matrices manage all EG and LFO routings, various MIDI parameters, and the Pattern Sequencer's control outputs. Output destinations include virtually all of the other module parameters. One nice touch is that the amounts for ten Modulation Matrices are provided as destinations for the other ten.

From a control standpoint, VirSyn's most unusual feature is its 8D Sound Access system (see Fig. 1). Each diamond is an x-y controller, and each dimension of each diamond can be mapped to as many as eight parameters, allowing you to control 64 synthesis parameters, each with its own range and direction. You can assign each of the eight dimensions to any MIDI controller or manage it onscreen with the mouse.

The Speed slider at the left of Fig. 1 sets the transition rate from one position to another; its value affects MIDI as well as mouse control. The ability to specify a controller's response makes for smooth gestural control; it is especially handy when you're using the mouse, because a single click can initiate a gradual transition between positions. 8D Sound Access takes a bit of time to set up, but the results can be unique.


A VirSyn Project can have as many as 12 Parts. Each Part contains a complete polyphonic synthesizer (with 32-note maximum polyphony) and a Pattern Sequencer with 256 Patterns of 64 steps each. VirSyn also provides a 256-step Song Sequencer. Each Song step calls up a Pattern from the Pattern Sequencer, and you can specify the number of Pattern repetitions and which Parts are muted; that is, unmuted Parts play the chosen Pattern number from their individual Pattern Sequencers.

VirSyn's Part Mixer controls the overall mix, governing the level, pan, global reverb, and chorus send and return for each Part. The Part Mixer is also where you assign each Part's MIDI channel, MIDI note range, and number of voices. The MIDI channel assignments can overlap to create keyboard layers and splits among the Parts.

The Pattern Sequencer is quite extensive (see Fig. 2). Each Pattern includes a pitch sequence and two control sequences. The pitch sequence is hardwired to the synthesizer's overall pitch, but you can route the control sequences anywhere using the synthesizer's Modulation Matrices. Each step has its own gate time and note value (whole to 32nd note — standard, triplet, or dotted) as well as Skip and Mute buttons. VirSyn can automatically convert each step to a chord; it provides every inversion of almost any three- or four-note chord type.

One of the Pattern Sequencer's most interesting features is its Arpeggiator mode, in which holding as many as eight MIDI notes forms the basis for an arpeggio. You can assign each Pattern step to a specific arpeggio step (in pitch order) or to the next arpeggio step. The Pattern's pitch sliders set the transpose amount for the selected arpeggio step.


VirSyn is a versatile package that offers much in the synthesis and sequencing departments. The emphasis is clearly on functionality; what the interface lacks in design aesthetics is more than made up for in ergonomics. For example, you can use the computer keyboard to adjust each control with three levels of precision. Pop-up indicators describe each control as the mouse rolls over it, but the pop-ups are delayed so that they don't appear when you're working quickly and presumably don't need them. In addition, detailed, context-sensitive help explains each module and control.

VirSyn's printed manual (yes, you actually get a manual) is complete, well written, and clearly translated, despite occasional lapses into German. VirSyn supplies plenty of factory patches to get you started. The six factory Projects (which match the demo MP3 files) are limited in scope, but they at least give you a running start.

VirSyn's price tag is relatively low for a modular software synthesizer with so many features. The VST version is a real bargain, despite the fact that it lacks a Pattern Sequencer and global effects — those are functions that are usually fulfilled by the VST host, anyway. Take a test drive and listen to the MP3 examples; it's definitely worth your time.

Minimum System Requirements


Pentium II/200; 32 MB RAM; Windows 95; DirectX 5.0; compatible sound card; compatible MIDI interface; VST 2.0-compatible host (for VST operation)


VirSyn 1.1 (Win)
software synthesizer



PROS: Functional, well-thought-out user interface. Flexible and CPU-efficient synthesis engine.

CONS: No overall patch view. Somewhat limited audio signal path mixing. Key-disk authorization.


tel. 49-72-4020-2956