Analogue Modelling Synth
Reviews : Keyboard
The market for 'virtual analogue' synths has become somewhat crowded of late, but that doesn't seem to deter manufacturers from pitching new models into the field. The latest of these is the long-awaited Oberheim/Viscount OB*12, which recalls, at least in name, the classic Oberheim OBX and OB8 analogue polysynths. However, the original Oberheim company and design team are long gone, the name serving only to add a little historical authority to products designed and manufactured by Italian company Viscount; and although the new instrument has only just reached the shops, rumours are already flying in analogue anorak circles that, where the original OB-series instruments were 'fat' and 'rich', the OB*12 has been condemned as 'thin' and 'digital-sounding'. But is this really true, or is it just misinformed prejudice? And if it were true, would it stop the OB*12 from being a good synth?
Physically Speaking
The OB*12 is a little larger than you might expect for a four-octave synth, but its pressed steel chassis ensures that it's built like a tank, and even the fake (plastic) wooden end cheeks can't detract from a general air of purpose. With lots of space between its numerous knobs and buttons, a large screen,
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Like many other DSP-based synths, the OB*12 provides a large number of controls on its top panel, sufficient to create and tweak a huge range of analogue-esque sounds, and offers many more options in menusassociated with each section. This is where its large display proves so valuable. Whereas the last DSP-based synth I reviewed offered just a pokey 2 x 20-character display, the OB*12 has a 240 x 64-pixel screen that displays its parameters graphically. This means that you can see the positions of the 'virtual' sliders, and view the envelopes (and so on) in their full glory as you edit them. This earns Viscount a fistful of brownie points. Accessing these graphics is simple: provided that you don't instruct it otherwise, the Obie will jump quickly to the appropriate page when you touch a control. Alternatively, you can press the relevant 'Edit' button and select the page you want.
The OB*12 is capable of 12-voice polyphony and four-voice multitimbrality, and provides two sound-generating modes. An OB*12 'Timbre' is what you might normally call a patch, and this offers nine edit pages, most of which are duplicated on the control panel. Viscount have named the level above this a 'Program', although you would more often think of it as a Multi, Combi, or Performance, and this has 10 edit pages. Since the Timbre is the fundamental level of the OB*12, let's start there...
The Oscillators
The sound engine comprises two oscillators, a ring modulator, a noise generator, two filters, an amplifier, and two LFOs. It's all very traditional and analogue-esque but, under the hood, the OB*12 has some impressive extra features. Take Osc1 as an example. In best analogue tradition, this offers sawtooth, triangle and pulse waveforms, the last with PWM controlled by either LFO1 or the oscillators' dedicated three-stage (Attack, Decay1/Break, Decay2) envelope generator. In addition to this, the sawtooth has a waveshaper similar to Roland's 'supersaw' facility. This adds a detuned second sawtooth that creates rich, chorused sounds from a single oscillator. Similarly, the triangle has a waveshaper, although it's a weird one: it increases the amplitude of the triangle so that it 'wraps' around the upper and lower limits, generating complex sounds that are very digital in character. You can mix the outputs of any combination of the three waveforms using the three Wave Mix controls in the Osc1 panel, add modulation from either LFO, and apply FM (cross modulation) from Osc2. It's a powerful package, and I like it very much. From the simplest and most common timbres to complex digital sounds rich in overtones, it's all in there.
Osc2 shares Osc1's waveforms and mixing capabilities, but lacks the waveshaping of the triangle and sawtooth waves. Instead, it offers coarse (±24 semitones) and fine (±50 cents) tuning controls, keyboard tracking on/off (so that you can use it as an audio-frequency modulator) and 'sync'. This means that you can cross-modulate Osc1 from Osc2 while simultaneously synchronising Osc2 to Osc1. The results can be wild: I created one Timbre in which the pitch tracking above middle C was greater than 1:1 while, below that, it was inverted. As you might imagine, this gives the OB*12 considerable 'sound effects' potential.
The oscillator mixer and envelope controls reside in the Oscillator Common section. The mixer is as odd as any I've ever seen. On the left, fader 1 balances Osc1 and Osc2. Fader 2 then balances the mixed oscillator signal with the output from the ring modulator. Fader 3 balances the balanced Osc1/Osc2/RM signal with the output from the noise generator. If this seems straightforward, ask yourself how you would set the faders to mix the outputs from Osc1, Osc2, the ring modulator and the noise generator equally. The answer is: fader 1 at 50 percent, fader 2 at 33 percent, fader 3 at 25 percent. Not so obvious, huh?
The ring modulator itself is excellent. It's very clean with no associated noise or digital artefacts, and it responds correctly when you present complex signals to its input. Unfortunately, some players associate unwanted side-effects and distortion with the modulated sound itself, and those people may find the ring modulator in the OB*12 to be somewhat lacking in character.
On the front panel, the oscillator envelope offers just Attack and Decay controls but, when you delve a little more deeply, it reveals its true nature. It's a four-parameter contour with Attack, Decay1 Time, Decay1 Level and Decay2 Time settings. This produces shapes that are not possible using conventional ADSRs, allowing you to swoop above and below the notional 'zero' line during the course of the contour.
The Filters
The next stage in the signal path is, of course, the filter section. This offers two filters that you can configure in three ways. The first of these is 'Serial', wherein filter 2 follows filter 1. The second is 'Parallel'. In this, the signal is split into two paths; one passes through filter 1, the other passes through filter 2, and the two are recombined after filtering. The third is 'Split', which allows you to determine which oscillator signal is modified by which filter. This is sexy stuff.
The filters themselves can assume four guises: high-pass, low-pass, band-pass and 'flat' (ie. off). All the web sites I could find on the Net describe them as 24dB/octave filters, but I can find no su
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The dedicated filter envelope is the fourth modulation source. Looking at the top panel, you will be misled into believing that this is a simple ADSR. However, touching one of the sliders takes you to two edit pages called 'ADSR' and 'ADV-ENV'. The latter allows you to configure six-stage envelopes with a Hold segment before the Attack, plus two Decay stages separated by a Break Point. It also adds an optional Sustain Time parameter that limits the amount of time that the filter remains at the Sustain Level. I can't recall having seen this parameter elsewhere, and it makes an interesting addition.
You can offset the filters' cutoff frequencies to create profiles with 'knees' (as you can with the filter on the EMS VCS3), configure powerful 'formant' filters, generate 'band-reject' profiles, and more. Unfortunately, there's only one envelope for both filters, no matter which configuration is active. This means that both cutoff frequencies will always follow the same contours.
The Amplifier And Modulators
The amplifier provides an envelope similar to that available to the filters, offers modulation from LFO1 and LFO2, allows you to position the signal in the stereo field, and also adds stereo panning (determined by the rate and waveform of LFO1). Which brings us to the LFOs themselves...
On the top panel, LFO1 offers just three controls. These are Rate, Fade (gradual fade-in of the amplitude), and a button to select between the four available waveforms: sawtooth, triangle, square, and 'random'. Tucked away in the menus there's also a Delay parameter that determines a length of time before the onset of modulation. But the most interesting feature is the dedicated filter that slews the signal from the LFO. The effect is much like applying portamento to an audio signal, and it smoothes the modulations to create subtly different effects. Nice.
LFO2 is similar to LFO1, but with six destinations -- Osc1 frequency, Osc1 PWM, Osc2 frequency, Osc2 PWM, filter cutoff frequency, amplifier amplitude -- instead of seven. (The missing one is Autopan.) However, unlike LFO1, LFO2 allows you to control the depth of the modulating signal using the modulation wheel. Unfortunately, I discovered a strange little bug in LFO2. If you apply the LFO2 triangle waveform to the amplifier to create tremolo (a common requirement), it exhibits a little hiccup between cycles. This does not happen with the other LFO2 waveforms, nor when you apply the LFO2 triangle to other destinations. Weird!
Keyboard Mode
Once you've created a Timbre, the 'Keyboard' panel allows you to tailor it for your performance. This panel includes portamento, voice reserve (for multitimbral use), octave shift for each oscillator, unison, and
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Unison is interesting. It allocates three voices to each note, thickening the sound, but reducing polyphony to just four notes. The combination of unison and detune then works in a novel way. For example, if you set the coarse detune to one semitone and play a C, the lowest of the three voices will play B, the highest will play C#, and the central one will play the C itself. Fine detune uses the same philosophy, flattening one voice while sharpening another. This creates some extremely lush sounds indeed. The final unison parameter is FINE RND INFL, which stands for Fine Detune Random Influence. This specifies the degree of random variation that occurs in the fine-tuning of each of the voices comprising a unison note, imitating the natural variations that occur when you use a genuine multi-oscillator analogue synthesizer. Bravo! Unfortunately, the OB*12 seems unable to handle four-note chords in unison mode, playing some notes instantaneously, while others follow a fraction of second later. This has all the hallmarks of inadequate processing power, so I hope that it's a software problem!
Mono mode does much more than reduce the available polyphony to one. For example, you can select the note priority, choosing between highest-note, lowest-note, and most recent note priorities. Furthermore, 'Legato' allows you to choose between multi-triggering and single triggering. These six combinations allow you to emulate almost every monosynth, so you can programme the OB*12 to perform like your favourite vintage instruments.
Now we come to the controllers. The OB*12 is well endowed in this department, offering the aforementioned velocity sensitivity, aftertouch, ribbon controller, and pitch and mod wheels. There are nine keyboard velocity response curves, including two 'reversed' responses for special effects, and you can direct these to any one of 19 Timbre parameters. Likewise, there are eight pressure response curves with 15 destinations.
The Ribbon is more powerful than either of these. This is because you can assign two parameters to it simultaneously, determining the minimum and maximum amounts of effect for each. Destinations? No
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The Programs
Once you have created a Timbre, you can name it and save it in any of 256 memory locations. However, this is only the first stage in creating a complex sound. Each Program (of which there are also 256) offers space for four Timbres, and you can determine whether each of the four slots is enabled or disabled, and choose the Timbres that occupy them. You can set the Level for each Timbre, its transposition, and high-key/low-key ranges for each, allowing you to layer and/or split Timbres across the whole MIDI note range. Having done this, you can determine which Timbre appears at which of the four outputs, either individually, or as stereo signals across the Main L/R or Aux L/R pairs. This is important, because the OB*12 allows you to rearrange its effects to lie on the busses in no fewer than 242 different configurations. Thankfully, the large screen makes this painless, and it's yet another example of the OB*12's well-thought-out user interface.
And what of the effects themselves? Firstly, there are 16 overdrives, with which I wasn't overly impressed. Many dulled the signal considerably and, worse still, a Timbre passed through the overdrive reverts to mono. This, in my view, is a huge cock-up.
The chorus is a stereo unit with pre-delay, rate, depth, feedback, and level controls. This allows you to dig deep into '70s chorus/echo. Great fun! But if the chorus is 1975 revisited, the delay is even more so. It offers the expected controls -- time, feedback, high-frequency damping and level -- but includes modulation with depth and rate controls. The effect is quite unlike chorus, with each delay having a different pitch offset. The results can be radical.
Lastly, the reverb offers two halls, two rooms, a plate, and 'vocal'. Each has pre-delay, high-frequency damping, reverb time, and reverb level controls, and all are perfectly serviceable. Apart from the overdrives, my only real criticism of the effects is that there is no 'mix' control within any of them. A Level control is not as good because you can not replace the original signal with the effected one.
In addition to what Viscount call 'the effects', the OB*12 also boasts an equaliser. This operates as a five-band graphic with bands centred on 60Hz, 200Hz, 600Hz, 2kHz, and 6kHz, or as a three-band parametric with low shelf (60Hz), high shelf (6kHz), and a central EQ with controls for frequency, Q, and gain. Very useful it is too.
Arpeggiator
The OB*12's arpeggiator is, in direct contrast with the Phrase Recorder (see box) nice and simple, with traditional up, down, alternating and (hurrah!) random modes, ranging over one to four octaves. If you are in Program mode you can select which part(s) are affected by the arpeggiator, and/or define a 'Split' key, above which the notes do not contribute to the arpeggio. You can also select the velocity of each note in the arpeggiating pattern, which can be either: as played; fixed at MIDI velocities 40, 64 or 100; or set to the velocity of the hardest note played. Most interestingly, there are two arpeggio modes. Regular encompasses steady tempos from quarter notes to 1/32nd notes and includes triplet beats. Irregular has seven options with all manner of strange dotted this, that, and the other beats. Seriously weird and, in the right context, you'll love it.
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Morphing And Motions
The Automations section contains the final two major features on the OB*12. The first of these is Morph. No, not the little plasticine man, but the ability to morph one Program or Timbre into another. You can control this in two ways -- manually using the mod wheel, or in Auto mode. The latter offers a Time option (an uncalibrated number between 1 and 100) and a Measure option linked to the arpeggiator or Phrase Recorder tempos.
Morphing, on any synth, is prone to limitations. For example, how do you morph between parameters which are simply off in one patch and on in another, or between filter types? Viscount's answer to this is to limit the morph function to the continuous parameters within the edit structures. Any non-continuous ones are set to those of the destination sound. This means that, once you select Morph, the source sound (which is probably what you will be playing at the time) may change considerably. This becomes especially apparent when parameters such as arpeggio on/off are different on either side of the morph. Indeed, until I understood what was happening, I thought that Morph was buggy. It isn't. In fact, the only way that I could cause anomalous behaviour was to jump rapidly between destination patches while playing and morphing simultaneously. And what happened? A system crash? Smoke billowing from the back? No... the OB*12 placed a 'Temp' patch in the source location, and carried on as before.
I found that I used Morph in two ways. When programming Timbres, I chose wildly differing sounds and morphed between them, discovering new Timbres that I could then save to other memory locations. Alternatively, when soloing, I placed two similar Timbres in the source and destination locations, and used the mod wheel to change the nature of the sound. This is much more expressive than common modulation.
The Motion Recorder is similar to the Phrase Recorder, but allows you to record every knob twiddle, button push, or fader adjustment while you play. There are just two memory locations, but you can use these to store and reproduce complex changes that you can later apply to any sound you're playing. The Motion Editor is also very similar to the Phrase Editor and, since Motion events have no duration, I found it to be bug-free. Indeed, the Motion section is a joy to use and, since I don't have a Roland JP8000 (the only synth I know of with a similar feature built in), I had a lot of childish fun.
Putting It All Together
Due to the late availability of the latest OB*12 operating system, and an unfortunate clash with production deadlines, I feared that I wouldn't have as much time as I wanted to evaluate it. However, most of the OB*12 is so simple and intuitive that, within a couple of days, I was flying around its controls and menus as if I had owned it for years.
Many of the OB*12's best facilities are underused in the factory sound set, and this is perhaps the major reason why the casual punter will be less than impressed with a store demo. Since so many of the factory Timbres were uninspiring, however, I was soon creating banks of my own. With time-honoured tradition (I do this on every synth I review) I patched my favourite ARP Odyssey trumpets and tubas. Gorgeous. I then tried my hand at a range of lush pads and string ensembles. Even without the onboard effects, programming these was trivial, and with the effects... lovely! Digital, PPG-ish sounds? Easy, and that's no mean compliment. Sound effects? Also easy. Brass stabs? Loads of 'em. Electric pianos? Simple. Harsh 'rip yer 'ead off' sounds and effects? Yep, them too. Analogue percussion? No sweat. Driving, punchy basses? Well, taking a lot of care and time over the programming, I managed to get some reasonable results, but it wasn't easy. And when it came to Organ sounds, I'm afraid it was beyond me. I spent a whole evening trying to program a usable rock organ, without success. I got reed organ-like tones without too much trouble, but nothing you really could call Hammond-like. For some unfathomable reason, the OB*12 seems incapable of these. And powerful leads? Sorry, not a chance. When it comes to the crunch, the OB*12 won't perform outside its main strengths.
Maybe I shouldn't care -- after all, there are dozens of synths that exist solely to pump out imitations of the Minimoog. But the Obie's limitations may restrict its appeal somewhat.
I then progressed on to designing some multitimbral Programs. It's no secret that I'm a huge admirer of Vangelis (who was not a big user of Moogs and other 'fat' synths) so I decided to create something in the style of his earlier solo work. I wanted a lush, chorused string ensemble under my left hand, layered with an arpeggiated bass. Under my right hand, I wanted a warm ARP-ish brass solo, together with a deep filter sweep. All of this needed to sound like it was coming from a large acoustic space, but without being muddy.
No problem! I chose an empty Program, placed four suitable Timbres into it, and set the upper and lower key ranges for each. I then directed the arpeggiator to just one Timbre
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So what are the problems? On the sound-creation side, you have to be careful not to overdrive the filter input at maximum resonance. The result is digital distortion, which is always horrid. On the other hand, the filter displays remarkably little digital stepping or glitching, even when tweaked violently by hand, so I'll forgive it any minor indiscretions. More annoying than this, the envelopes always re-trigger from 'zero'. If you program Timbres with slow attacks and releases, this results in an unnatural 'chopping' of the sound, particularly noticeable on string ensembles and other pads.
More deficiencies? Well, I encountered a couple of bugs in the editing, but these appeared rarely, and were never reproducible. Also, there's an uncomfortable mute when jumping between Programs and Timbres. However, you can set any Program to 'Single' mode, and the four Timbres within it then become four instantly accessible patches under the immediate control of the Part Select buttons. Anything missing? I would like to see some patch navigation aids and, of course, there's the limited polyphony. But perhaps the most serious fault is the OB*12's inability to handle chords in Unison mode or when multiple timbres are layered two, three or four deep. Viscount must cure this.
Conclusions
The OB*12 is not going to be everybody's cup of virtual analogue tea. I'm certain that the blippy, bloopy, squelchy dance brigade are not going to be its biggest fans, and, since its greatest strengths are pads, delicate sounds, and effects, it's not a lead synth for the prog-rockers either. As a result, I worry that it could suffer a fate similar to that of the Elka Synthex, a synth which was overlooked by most people, and disappeared without much of a ripple. But with the Synthex, a few years passed, and then you started to hear players mourning its demise. Despite its deficiencies in some important sonic areas, the OB*12 is almost a great synth; and I hope in the space available to me here I've managed to convey a sense of how deep it is. With its parameter-rich VA voicing, assignable busses and effects, arpeggiator, sequencer, motion recorder and morphing, it's similar to much more expensive synths such as the Waldorf Q, so it's a shame that Viscount's marketing gives you little sense of this. And then there's the price: at just £799 the OB*12 is in the same league, price-wise, as a Korg MS2000. That's quite a price/performance ratio! Whether all this depth has enough mass-market appeal to result in a 'hit' synth for Viscount, however, is up to the likes of you.
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