The Access Virus C, a tabletop module from Access Music, is the third incarnation of the popular analog-modeling synthesizer.
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The Access Virus C, a tabletop module from Access Music, is the third incarnation of the popular analog-modeling synthesizer.

FIG. 1: The Access VirusC is the third incarnation of a tabletop synth module that has inspiredlegions of enthusiastic fans. Plenty of front-panel controls make theVirus C a tweaker's delight..FIG. 2: On the Virus C'srear panel are connections for analog audio, MIDI, a pair of footcontrollers, and an external power supply.

The Access Virus has been around through three incarnations —first the Virus A, then the B, and now the C. The original Virus wasone of the earliest and most popular virtual analog synthesizers,digitally generating and processing sounds by crunching numbers ratherthan by manipulating voltages. The latest generation continues thetradition of providing all the functions of a real analog synth andmore, packaged in a compact form that offers plenty of hands-on control(see Fig. 1).

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Four models — the tabletop Virus C, Rack XL, Virus kc(five-octave keyboard), and Indigo 2 (three-octave keyboard) —have identical DSP engines that physically model analog synthesis. (ATDM software version of the Indigo is available for Pro Tools, too.)The user interfaces are identical as well, with the exception of theRack XL's conservative five-knob front panel. For this review, I testedthe tabletop Virus C.

The Virus C's new DSP chip is an incremental step up — thougha large one — from the previous Virus B units. Polyphony has beenincreased from 24 to 32 dynamically allocated notes. Flexiblemodulation routing has always been a significant element of the Virusarchitecture and sound; the number of simultaneous modulation sourceshas doubled to six, and modulation destinations have grown from six tonine. There are now 98 simultaneous effects in multitimbral mode, andeach of the 16 parts has 3-band EQ, phaser, chorus, analog boost, ringmodulator, and distortion modules. A global effects section providesreverb and delay.


I especially appreciate the Virus C's 32 knobs, 35 buttons, and 69LEDs. Having access (pardon the pun) to so many simultaneous controlsencourages the user to experiment and minimizes the need to navigatetoo deeply into buried menus. The functions and parameters are betterorganized in the Virus C than in the B models. Many of the dedicatedknobs are self-explanatory, but you'll still need to spend some timeacquainting yourself with the interface, as some functions are notimmediately intuitive. For example, you navigate System and Multi Editparameters using a combination of the Part, Parameter, and Valuebuttons. If you don't have the manual to guide you, however, it'ssometimes confusing to perform a simple operation (such as changing theLCD contrast) that doesn't have a dedicated knob or button.

I'm quite unimpressed by the Virus C's display. The red-on-red LCDlooks cool, but the only good viewing angle is directly overhead. Nomatter what the contrast setting, leaning back from the synth reallycuts down on readability, and the useful viewing range becomes evenmore limited when you move from side to side. The LCD is the onlysubstantially weak spot of an otherwise stellar synthesizer.

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As with previous generations, all models of the Virus C providethree pairs of outputs and a pair of unbalanced inputs (see Fig.2). The inputs let you route an external source to the Virus'sfilter, Saturation (a type of filter distortion that adds overtones),vocoder, and effects processor. The most obvious use for the inputs isprocessing drum loops and the like, but the Virus's Saturation andfilters sound so good that you can also use them to subtly ordramatically alter piano, guitars, or vocals in real time.

The nearly 200-page manual is well written except for a couple ofminor inaccuracies and a few grammatical and syntactic errors in thetranslated German text. The manual does a fine job of detailing theVirus's various features and functions without becoming a laboreddissertation. It supplies an excellent introductory tutorial thatacquaints you with the Virus and explains the basics of traditionalanalog subtractive synthesis. A PDF tutorial document on the AccessMusic Web site is a superb resource for analog synth programming and amust-read for synthesizer enthusiasts.


The Virus ships with 512 Programs and 128 Multi setups, but you candelete the internal demo and increase the number of Programs to 1,024.All 1,024 Programs are supplied on CD-ROM, but you can overwrite any ofthem with user sounds. Because the factory sounds are so good, though,you'll want to keep them available; to that end, the Virus ships with aVirus-only version of Emagic's SoundDiver editor-librarian software forthe Mac and Windows.

SoundDiver Virus really helps with certain aspects of programming,and its librarian functions are essential for Program management. TheAccess Music Web site continually offers downloads of new Programs fromprofessionals and hobbyists alike. Even before you start creating yourown sounds, the number of available Programs for the Virus is easily inthe thousands. SoundDiver Virus is a more elegant way to keep up withPrograms and Multi setups than simple SysEx dumps.

Each Multi, including layers and splits, can contain as many as 16Programs. Each Multi has its own tempo, volume, transposition,detuning, and output assignments that override those at the Programlevel. It's a drag that you can't offset any filters or envelopes atthe Multi level — a feature found in units as simple as theRoland Sound Canvas. However, the Virus C provides so many RAMlocations that it's not a big deal to edit a Program and save it to anew location for use in the Multi, and you can still modulate Programsin Multi mode.

A single Virus sound can have as many as three oscillators (four ifyou count the suboscillator). But because engaging oscillator 3 reducesthe polyphony from 32 to approximately 24 notes, many Programs use onlytwo oscillators. A variety of waveforms are available, with many stepsin between that gradually change the shape from one form to another.The Virus lets you step through wavetables as you can in the PPG Waveand Korg Wavestation. Noise, FM, ring modulation, and sync features arealso available for all three oscillators.

The Virus's filters are simply outstanding. The dual resonant,multimode filters can operate independently in lowpass, highpass,bandpass, or band-stop modes, either in series or parallel. They offerfour filter slope and routing choices: Serial-4 (two poles per filter);Serial-6 (four poles for filter 1 and two poles for filter 2);Parallel-4 (two poles per filter), and Split (identical to Parallel-4,but with an independent input to each filter). When the filters are inSplit mode, oscillator 1 is linked to filter 1, and oscillators 2 and 3are routed to filter 2; the results are panned hard left and right,respectively. A dedicated Filter Balance knob adjusts the outputbetween the two filters; modulating the Balance sounds very cool.

Regardless of the filter routing, the Saturation stage alwaysfollows filter 1. Ten Saturation types range from mild to wild. You canmodulate Saturation using a knob, envelope, or LFO. In addition tocreating distorted sounds, the Saturation effect is useful in subtlerways to simply fatten up timbres. Modulating Saturation has become astaple of the Virus sound, and it's not likely to fall out of fashionfor a while.

Each Program has three LFOs. An envelope mode allows each LFO tocomplete one cycle and then stop, which is useful for further modifyinga sound's attack transient stage. LFO 1 and 2 can be synced andassigned to any destination. A modulation matrix provides six sourcesand nine destinations for more elaborate mod routings. In addition tothe mod matrix, Note Velocity has its own dedicated modulationrouting.

Using knobs to modulate Virus parameters in real time is a gas. Forme, it has made electronic music fun again, because I can work morequickly than I can using software. Because the latest OS increases theinternal clock's resolution, the Virus can follow a multitude ofsequenced modulations and drastic tempo changes simultaneously withoutthe slightest hiccup when it's synced to MIDI Clock.


The Virus C is one of the best-sounding synths I've ever laid myhands on. I've either owned or used a variety of classic synths overthe years, and I have a great collection of modern softwareinstruments, but the Virus C is my favorite. Ballsy basses, sweet pads,otherworldly atmospheres, screaming leads, vocoder effects, pulsingarpeggiated beds, electronic percussion — you name it, the VirusC does it. The Virus can transparently float in the background like asheer veil or stand shoulder-to-shoulder with heavy-metal guitar. Thissynthesizer is so versatile and sounds so impressive that it mightnever go out of style.

The Virus has become the first place I turn for synth basses, pads,and arpeggios. The subbasses can rumble the pictures off the walls;when I layer them with some of the throatier bass Programs, thecombination sounds killer on everything from a huge audio system with asubwoofer to a little Auratone mono cube speaker. I used to spend a lotof effort programming and processing to create massive bass sounds thatstill sounded good on little speakers, but thanks to the Virus, nowit's a piece of cake.

I love the Virus's transparency. Some synths are all meat, andothers are thin as air; the Virus can be both. I have found and createdpads that are so diaphanous that you hardly know they're there. I'veused them to outline chord structures behind an acoustic guitar andvoice, for example, without disrupting the basic feel of a simple duo.I set up the Saturation and oscillator balance to slowly fade in thesound's thicker elements. The result is like a transparent ghost thatcan slowly materialize into a solid form — a production techniquethat doesn't make the guitar and voice sound overproduced.

The Virus's envelopes have a very fast attack — somewherearound 20 µs — allowing the Virus to sound extremely punchy.Coupled with the signature Saturation stage, the Virus can rip and roarwith the heaviest guitar rigs. Basses thump and lead sounds blaze.Nasty industrial sounds are usually just a few knob turns away. If theenvelopes aren't enough, a Punch parameter adds even more oomph to theattack.

The Virus supplies a handful of analog drum and percussion sounds,but most are haphazardly scattered around the various Banks. It canemulate practically any analog drum machine, and several synthesizedcollections are available on the Web. I usually prefer the punchinessand beefiness of the Virus's sounds to most of my analog drum samples.Granted, a lot of ready-made analog drum samples are out there, but ifyou don't have a collection of vintage drum machines, it's refreshingto have so much control over percussive sounds rather than beinglimited to a sample's static nature.


One of the features that first attracted me to the Virus was itsimplementation of arpeggiators. Forty preset patterns are available,some of them quite complex. All are geared toward 4/4 meter rhythms,however; perhaps a future OS update will provide programmablearpeggiators that support odd rhythms. The next update, which should beavailable by the time you read this, will include 24 additionalpatterns.

In the past few years, the Virus's stock arpeggio patterns havebecome classics heard on many hit tunes. The usual suspects areaccounted for: up, down, up/down, random, as played, and block chords.You can specify the Velocity, octave range, swing percentage, clockmultiplier, and note length.

Sixteen arpeggiators are available in Multi mode, with one assignedto each part or with multiple arpeggios assigned to a single channel.You can have 16 independent arpeggios running on a single sound,allowing you to create ostinatos that are truly inspiring — youhave to hear it to fully appreciate it.

Although the arpeggiators lack a dedicated tempo knob, you canassign one of the two soft knobs to control tempo. However, I'd ratherleave the soft knobs for more important assignments, such as number ofoctaves or note length. Unless you're viewing the Edit menu, tempoisn't displayed in beats per minute (bpm); rather, because the softknobs are unaware of what parameter you're editing, tempo is shown inarbitrary values from 0 to 127. Most of the time you'll probably wantto sync the Virus to a sequencer anyway, so perhaps it's not a bigdeal; tempo chases MTC flawlessly.


I love this box. I had grown bored with tweaking electronic sounds,but the Virus C helped me regain my enthusiasm by making it so simpleand intuitive to grab knobs and start turning. I haven't even mentionedthe vocoder, which offers as many features as almost any dedicatedvocoder. I also like the Random button that generates new timbres onthe fly when you're feeling stuck; I've created some great sounds usingthat feature as a jumping-off point. It's just impossible to cover thissynth thoroughly within the scope of a review.

I do have a few criticisms: I'm not crazy about the LCD screen, andI'd rather have a dedicated internal power supply than the Virus'slump-in-the-line external supply. Digital audio ports would be awelcome addition. And as great as the arpeggios are, I hope for evenmore features in future OS updates.

Access Music has maintained an excellent policy of frequentlyupdating its products, old and new alike. The company obviously wantsto add as much power and as many features as the original hardwaredesign will allow, which has led to significant updates for Virus A andB owners in the past. That policy makes me even more comfortableinvesting in a Virus product, because it's been demonstrated that I canexpect more features in the future.

But it's the filters, Saturation, arpeggiators, and modulationcapabilities — and especially the sounds — that make theVirus C so desirable. If I could own only one synthesizer strictly forelectronic sounds, it would be the Virus C. Its tabletop form factor isperfect for me because it's compact enough to transport easily, yetit's very easy to program. Whenever I put the Virus up against most ofmy other synths — hardware or software — it makes themsound kind of puny. The Virus C's heavyweight, professional tone putsit in the league of the elite.

Producer and musicianRob Shrockhas worked withBurt Bacharach, Elvis Costello, Dionne Warwick, and manyothers.


Virus C
analog modeling synth module



PROS: Killer sound. Smooth parameter control. Excellentarpeggiators. Random Program creation.

CONS: LCD hard to read at certain angles. Somewhat complexmenus and interface. Arpeggio patterns only in 4/4 meter. Scrollingthrough sounds by category requires two hands. Lump-in-the-line powertransformer. No digital audio I/O.

Access Music/GSF Agency/TSI
International Sales (distributor)
tel. (310) 452-6216


If you're a fan of electronic-music timbres, I suggest wiring theVirus's inputs to your patch bay so that you'll always have themreadily available as part of your everyday working setup. (The TDMversion also allows you to process external signals.) As much as I loveplug-ins in general, I find processing with hardware more desirablebecause it's more immediate, it allows me to process soundsbefore they're recorded, and it simply sounds better. (I'verecently become enamored with taking some of my detailed orchestralstring sequences and processing them through the Virus for a sort ofupdated Electric Light Orchestra sound.)

I like to route good sounds from other synths through the Virus tocreate even better sounds. You can use your sequencer to record anyparameter modulation you apply. You can also route external sourcesinto the Virus unaffected, bypassing the internal DSP engine and simplymixing the external input with the Virus's output without an externalmixer.

Whether or not you're processing an external source, the Virus canboost its input level as much as 20 dB before and an additional 36 dBafter A/D conversion. It can accommodate a wide range of levels, from amicrophone to an electric guitar to a turntable, but significantinput-level boosts can increase the source's noise. If you're usingextremely low-level sources, then it's better to use a preamp or otherhigh-quality gain stage. Still, it's convenient that the Virus's inputscan deal with just about any source level when necessary. The Virus hasa phono-input setting with a special EQ curve to accommodate thefrequency response of record players — perfect for DJs who wantto use the Virus alongside a turntable.

Virus C Specifications

Sound Engine

analog synthesis modeling


(32) notes

Multitimbral Parts


Analog Audio Inputs

(2) unbalanced ¼" TS

Analog Audio Outputs

(6) unbalanced ¼" TS; (1) ¼" stereo headphone

Digital I/O


MIDI Ports

In, Out, Thru

Additional Control Inputs

(1) ¼" TS switch; (1) ¼" TS pedal

Program Memory

(1,024) Programs; (128) Multis (all rewritable)

DSP Resolution

24-bit internal; 24-bit D/A; 16-bit A/D


(3) main and (1) suboscillator per voice; sawtooth, pulse, sine,triangle, and 62 spectral waves; FM


(2) multimode (lowpass, highpass, bandpass, band-stop); (4)serial/parallel configurations

Envelope Generators

(2) ADSTR (T = time)


(3) with (68) waveshapes

Modulation Matrix

(6) sources; (9) destinations




(98) simultaneous: boost, chorus/flanger, delay, distortion, EQ,phaser, reverb, ring modulator, vocoder

Power Supply

external in-line adapter


18.50" (W) × 2.95" (H) × 7.28" (D)


6.28 lb.