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Technosaurus Selector

Modular Synthesizer By Gordon Reid
Published May 1999

The review Selector sported three Octal Subharmonic Oscillators — but, sadly, they weren't working ones!The review Selector sported three Octal Subharmonic Oscillators — but, sadly, they weren't working ones!

Last month, Gordon Reid reviewed the babies of the Technosaurus range, the Microcon synthesizer and Cyclodon sequencer. This time, he tackles their (very) big brother, the Selector modular synthesizer...

The past two years have seen a proliferation of modular and semi‑modular synths that would have been unimaginable in the early part of this decade. The rush of new instruments started with the Doepfer A100, followed closely by the Analogue Systems RS Integrator, and then the Synton Fénix. There has also been a resurgence (so to speak) of Serge, and the introduction of a host of lesser systems such as the Canadian 'Modcan' and the as‑yet unfinished Concussor modules from Analogue Solutions in the UK.

None of these, however, exude the sheer sexiness of a Moog System IIIC, a Polyfusion, or even an ARP 2500. Why is that? It's nothing to do with the facilities offered, because a large RS Integrator incorporates everything a Moog or ARP has, and more. It's not the sound either because, contrary to anorak mythology, it's unlikely that many players could distinguish a good 1960s modular synth from a good 1990s modular synth. Ah... I know what it is. Sorry guys, but the girls were right all along. Size matters!

Enter The Bigg'un

You might expect that it would be the Americans who would first latch on to this. After all, in the USA bigger is better, taller is better, and if it ain't big enough or tall enough, a bag of silicone or a few hormones always seem to do the trick. But it's the nimble‑fingered Swiss — perhaps the supreme miniature jewellers and watchmakers of the world — who have produced the first truly monstrous synth of the late 1990s.

Mind you, not all Selectors are overpoweringly large. The System A is the 'baby' of the bunch. This comes in its own wooden cabinet, requires a mere 6U of rack space, and weighs 'just' 22kg. The suggested configuration incorporates three VCOs, a multi‑mode filter, dual envelope generators, a VCA, an LFO, and a dedicated MIDI‑to‑CV convertor. In some ways the patch‑less System 'A' isn't a modular synth at all because it's custom‑wired internally, but at least it offers inputs and outputs for the VCF and VCA.

The System 'B' offers the same space for modules as the 'A', but is 9U high and weighs an extra 3kg. The difference lies in the 3U patchbays associated with each module, and which sit beneath them in the rack. I love these patchbays. They're big, they offer oodles of options and, best of all, they take quarter‑inch jacks. Oh yes! There are no 3.5mm mini‑jacks here... now we're back in big Moog territory.

If the 'A' and 'B' are manageable, the System 'C' (you just knew that it would be called that, didn't you?) is the first of the big buggers. This offers two 'B'‑sized complements of modules, two 'B'‑sized patchbays, and a large central panel with the 'Selector' logo and two sets of multiples on either side. Not only is the 'C' larger, but the standard configuration offers a wider range of modules, too. This includes three VCOs, two VCFs, two single envelope generators, two dual‑envelope generators, two LFOs, two VCAs, two triple resonators, and a MIDI‑to‑CV convertor. The whole thing comes in a large wooden cabinet that stands more than a metre high, weighs in at a not inconsiderable 40kg, and angles the upper and lower module banks towards you. This imitates many of the huge systems assembled by Tangerine Dream in the late 1970s, so it's not a synth for those with geographically challenged studios.

Finally, we arrive at the Selector System 'D'. Twice the size and nearly twice the weight of the 'C', this is the Selector for anyone who wants to impress the neighbours. Large enough to conceal a dead relative, it has six oscillators, three octal subharmonic oscillators (of which more in a moment), three filters, three dual‑envelope generators, three triple resonators, four LFOs, four VCAs, and the ubiquitous MIDI to CV convertor. This thing is the bigg'un. Indeed, I couldn't get the 'D' into my studio so I had to bring the test equipment, amp and speakers to the synth, not the other way round. You've got to take the C's and D's sizes and weights into consideration before deciding to buy one. On the other hand, if you've got an empty wall that's just crying out for an enormous, electronic phallus, then this is your instrument! So let's stop slavering, wipe our collective chins, and take at look at what each of these 32 black and blue blotchy modules and patch panels offers.

The Oscillators

Each of the six VCOs produces four simultaneous waveforms with independent level controls and outputs for each. The waves are sine, triangle, sawtooth and square waves, and a couple of these sounded so 'true' that I couldn't resist loading them into my Roland S770 to view the waveforms. On inspection, the sine and triangle waves proved to be impressively pure. The square and sawtooth waves are necessarily less true to the ideal, but nonetheless as — or more — accurate than those of any other synths I have recently tested. This is not trivial: in the grand tradition of 'Garbage In, Garbage Out', purer waveforms lead to higher quality and more powerful sounds.

The square wave offers manual pulse‑width control, which ranges from a remarkable 1‑percent duty cycle to 99‑percent duty cycle (most synths offer 5 percent to 95 percent). There are also two CV inputs for pulse‑width modulation, and a knob that allows you to control the depth of the effect. Loaded into the S770, the 1‑percent pulse proved to be impressively narrow and, while not precisely pulse‑shaped (which is not surprising given the limitations of analogue circuitry) still sounded extremely thin and reedy.

Each VCO offers six footages ranging from 64' to 2', plus a fine‑tune control. If, however, you apply appropriate CVs, the fundamental can reach from less than 1Hz to over 12kHz. You can access this using a combination of the standard 1V/octave pitch CV input plus a selection of the five extra inputs and outputs provided. Three of these are pitch CVs (two with level controls) that are summed internally to provide complex modulation possibilities. These do not respond in tune to a 1V/octave CV, but offer a slightly wider range for more extreme modulation. (Technosaurus quote their response as 0.95V/octave.) The other two sockets are 'hard' sync inputs and outputs.

If you're tempted to think that the range of the Selector's VCOs makes dedicated LFOs unnecessary, think again. There are no fewer than four in a System D, and these have an exceptional range of 0.015Hz (one cycle per minute) to approximately 2kHz. At the top end, this makes all manner of FM effects possible. A single CV input allows you to modulate the LFO frequency itself.

The LFOs (which also include white and pink noise generators) offer the same four basic waveforms as the VCOs (with variable pulse width and PWM on the square wave) and again each has independent outputs. Strangely, the square wave output can carry any of the waveforms and the dedicated pink noise output can also carry white noise. This is, at first sight, odd, but it makes a great deal of sense when you think about how a single LFO module might be configured in the pre‑patched System A.

The review Selector sported three Octal Subharmonic Oscillators — but, sadly, they weren't working ones!The review Selector sported three Octal Subharmonic Oscillators — but, sadly, they weren't working ones!

Octal Subharmonic Oscillators

Now, I really don't want to be the one who has to tell you this but... the three Octal Subharmonic Oscillators (OSOs — see box below for more on these) in this System D are dummies. No, not in a vernacular sense of being 'no good', but literally — there is nothing inside them. So I contacted Technosaurus in Switzerland and asked the Head of Engineering what was happening. He told me that the OSOs are, as yet, still a gleam in the company's eye, although he hopes to have the prototypes finished in the next few weeks. Consequently, and despite what you might have read elsewhere, no‑one has yet heard an Octal Subharmonic Oscillator! Hmm... I think it's time to move on.


The three VCFs in the Selector are all called VCF2. This is because the VCF1 modules are also unavailable. Fortunately, that doesn't mean that your filtering options are limited, because each VCF2 is a multi‑mode filter with 12dB/octave low‑pass, 12dB/octave high‑pass, 6dB/octave band‑pass, and 6dB/octave band‑reject (notch) options. You select the cutoff frequency of the low‑ and high‑pass modes and the centre frequencies of the band‑pass and notch modes using the large, friendly knob that dominates the panel. You can then modulate this using any combination of the dedicated envelope CV input and the three FM inputs, all of which have associated level controls. And, if all this isn't enough, voltage‑controlled resonance is a particularly welcome addition. Very few synthesizers offer this, and it's a powerful feature that can make any instrument sound a cut above its competition.

The Selector's Triple Resonator is a sophisticated resonant formant filter module which can produce voice‑ and instrument‑like textures.The Selector's Triple Resonator is a sophisticated resonant formant filter module which can produce voice‑ and instrument‑like textures.

Even without VCF1s, the Selector offers three further signal modifiers in the form of its three Triple Resonators. Each of these is, in essence, a three‑band parametric equaliser with controls for centre frequency (32Hz to 8kHz), 'Q' (0.3 to self‑oscillation), and gain. Each band has a dedicated CV input that provides frequency modulation and you can, with care, 'play' the self‑oscillations over a small range. But if you do this, be very careful. I nearly ruptured my left eardrum when I carelessly whisked a Q knob down. The resulting transient all but blew a 150W speaker system!

If you choose to pass signals through the Triple Resonators (which is, of course, what they're designed for) there are four internally‑mixed signal inputs and a pair of audio outputs. There is also a CV input for amplitude modulation, and this allows you to modify the overall gain of the module. And the sound...? It's with good reason that resonators are often called 'formant filters'. You can coax many organic textures from them, including a wide range of human vowel sounds and the natural resonances of orchestral instruments. Of course, you may want to use them simply to screw up the sound, and that's no problem either.

There are 10 further sockets on the Triple Resonator's panel. These are 'multiples' — one bank of four and two banks of three — unconnected to the resonator itself. Added to the multiples in the VCA modules, they make just about any signal routing possible provided, of course, that you have enough patch leads. Which leads us neatly to...

Envelopes and Amplifiers

The Minimoog is revered, in part, because of the speed of its envelope generators. Although its front panel shows a fastest attack time of 10mS, common belief suggests that a Minimoog responds about 10 times faster. Now hold on to your hats...

Again using the S770 as a diagnostic tool, I set a Selector ADSR to 0,0,0,0 and used this as the CV for one of the VCAs. I then fired off a single trigger, and inspected the resulting waveform. I repeated the process until I believed what I was seeing. The rise time from the trigger to the maximum amplitude was typically eight samples. At a sample rate of 48kHz that's just 1/6000th of a second, or 167µS (167 microseconds). The fastest result I obtained was a blindingly fast five samples, which is only 104µS and consistent with Technosaurus's claim of 70µS for a 90‑percent response at the VCA's output.

Since I still couldn't believe this, I set up my Minimoog and performed the same test. Typical attacks lasted about 30 samples (625µS) which was much better than I had expected, but six times slower than the Selector! These results are incredible. It makes the Technosaurus far snappier than any other analogue you've ever heard, and adds an impact and presence that no other analogue synth can emulate.

Oops... amidst all this excitement, I've forgotten to tell you the envelope generators' specifications. The six EGs come as three dual devices, each of which offers DADSR (delay/attack/decay/sustain/release) and DAD (delay/attack/decay) profiles, with inversion if required. We've covered the fastest attack times in some depth, but it's also worth noting that the fastest decay and release times are also in the sub‑millisecond range. At the other extreme, the slowest times are around 10S, which is sufficient for most purposes.

The four independent VCAs are also highly specified. These are the only parts of the Selector's sound generation that aren't based upon discrete circuitry but, since the VCA itself is the same Analog Devices chip used in SSL consoles I think I'll forgive Technosaurus! Operationally, the module has three gain modulation inputs, two of which may be switched between linear and exponential responses, and one of which (AM2) offers both lin/exp and inverted options. An input gain control allows you to overdrive the VCA, and a tri‑coloured LED lets you know whether you are in the weak, clean, overdriven, or distorted ranges. The output has an independent volume control, and the output socket offers both unbalanced and balanced connections to minimise noise.

The VCAs' frequency responses are not all‑encompassing because, with a quoted minimum of 10Hz, you won't be able to pass slow LFOs through them. This shouldn't present a problem because the LFOs already have a wide range, but it's worth noting. And, to be fair, a 10Hz high‑pass response removes a potential source of speaker‑blowing danger.

On a brighter note, the maximum frequency of 20kHz ensures that you'll never lose high‑end sparkle. Add to this the claimed 100dB dynamic range and ‑90dB noise floor, and you have an analogue device that in principle exceeds the specifications of many 16‑bit digital products. Amazing!


The MIDI interface is the final module in the System D. This only responds to one MIDI channel (which is preset to your choice when you order) but it is very simple to use, with independent analogue outputs for pitch CV, Gate, velocity, aftertouch, pitchbend, mod wheel, and MIDI Controllers C1 and C2. I like this... it allows you to access all the common controllers without messing around with the menus of complex MIDI‑to‑CV converters. DIN Sync 24 and MIDI Clock options are also available as an upgrade.

In Use

The System D that arrived on my doorstep has lived a tough life. Shipped without any packaging (honestly... not even a plastic bag or a piece of brown paper to protect a £7,000 synthesizer!) it arrived dirty, scratched, and with two panels hanging loose. Amazingly, most of it still worked perfectly, although a few modules had decided that enough was enough. Worst affected, five of the EGs were either dead or acting strangely, and one of the oscillators didn't respond correctly. One of the Triple Resonators was also acting very oddly. But let's face it... no vintage Moog or ARP 2500 would have survived that treatment, whereas the Selector still allowed me to patch the sounds I wanted, and obtain a clear view of its abilities.

And what of those sounds? They are, to quote our American friends, 'awesome'. Although the current System D lacks many features found on instruments costing a fraction of its price, the quality of each stage in the signal path is unsurpassed.

For example, the ultra‑rapid envelopes place the Selector in a class of its own for drum and percussion sounds. Many producers sample analogue percussion and then remove the first few dozen samples to create an instantaneous transient at the front of the sound. Percussion sounds based on the Selector's 100µS attacks are, in the real world, just as punchy but they retain the analogue variation and interest otherwise lost in the sampling process.

Also of special note, the pure sine waves and the wide frequency responses of the VCFs and VCAs make sub‑basses a trivial exercise for the Selector. Just be careful that you don't damage your speakers.

Traditional analogue sounds also leap from the Selector, from screaming leads (handsomely abetted by the overdrive on the VCAs) to superb ARP‑ish flutes, brass, and woodwind emulations. Of course, you can't really say that this Selector sounds like a vintage Moog, an early ARP, or any other 24dB/octave system because its filters are so different. But it shares the same qualities: in turns it's fat, bright, and aggressive. I just can't wait to hear one with the VCF1s installed.

Inevitably, not all is sweetness and light, and the Selector lacks one of the most basic and important of all synthesis functions. There's no portamento! Also absent without leave (although some of these are due to appear alongside portamento on a planned pot‑pourri module) are voltage inverters, sequential switches, frequency dividers, voltage‑controlled switches, preamps, external signal processors... it's a long list. And then there are the lesser limitations such as the lack of voltage control for the envelopes, the noise sometimes generated by the Triple Resonators, and the audibly inconsistent transitions in and out of the VCAs' overdriven and distorted regions.

Another serious obstacle is caused by the EG trigger inputs, because they currently require about 8V to fire them. Since the outputs from the VCOs and LFOs attain a maximum of +5V, you can only trigger the envelopes using the MIDI‑to‑CV converter. This precludes many typical modular synth patches. Technosaurus has stated that its going to modify the EGs so that 5V will be ample to trigger them but, despite its size and sonic quality, there will still be some things that you can't do with a System D.


In many ways the Selector is the Minimoog of the modern world, majoring on classic sounds for playing music rather than silly noises for playing... well, silly noises. Like the Mini it's not as fully featured as you might imagine, and other, cheaper synthesizers have facilities that you'll not find on any Selector System. On the other hand, dedicated mixers and multiples are unnecessary, and a number of new modules have appeared since the review system left Switzerland.

But most important of all, the sound of the Selector is, in that gloriously indefinable way, just right. The reason for this is, of course, the quality of the engineering that has gone into every module. Accurate waveforms and sub‑millisecond envelopes don't occur by accident, nor are they cheap. As Jürg Oldani at Technosaurus told me, "I like to have a wide range of capabilities for most of the parameters. My philosophy is that extreme settings produce extreme sound capabilities. This has not yet been experimented with nor discovered enough by other synth manufacturers. That's one reason for the ultra‑fast envelopes. It makes sense to examine the extremes and that's the way I prefer to proceed with my developments."

If you've got the money and the ears to hear the difference, the Selector offers that sonic something that lower‑cost systems struggle to match. Furthermore, its large knobs and huge patchbays make it a tactile delight. But would you swap three RS8000s or seven Fénixes for a System 'D'? Only you can answer that.

More On OSOs

The idea behind the OSO is simple, but fiendishly clever. The basic oscillation is a sine wave, and you select its frequency and amplitude using an octave selector and a fine‑tune knob, plus the oddly named 'basis' control. You can then modulate it using a standard CV input and an additional FM input.

The next set of knobs, labelled 1 to 8, determine the initial volume for each of the sinewave sub‑oscillations. These follow a 1/(n+1) rule: that is, knob 1 controls a subharmonic of 1/2 the fundamental frequency, and knobs 3 and 7 control those of 1/4 and 1/8th the frequency. These are, of course, sub‑oscillators one, two and three octaves below the fundamental. But what of 'subs' 2, 4, 5, 6 and 8? These represent frequencies of 1/3, 1/5, 1/6, 1/7 and 1/9 the fundamental and have no relation to a standard harmonic series. This means that they are 'enharmonic' and capable of creating strange and wonderful sounds.

Once you have created a complex waveform, you can modulate the amplitudes of the 'even' subharmonics and/or the 'odd' ones. A high‑pass filter with variable cutoff frequency and two modulation CV inputs also allows you to sweep the lower enharmonics in and out of the audio signal.

I know that I can recreate this 'subharmonic synthesis' with the additive engine in my Kawai K5000S, and come close with a DX1 or DX5, but I love the idea of the OSO, and I can't wait to hear it. As for running three simultaneously... just lead me to them, please!

Here Today...

There are three Selector modules now available that were not supplied for review. The Sample & Hold should prove to be fairly standard, with internal and external clock options, and an internal noise source or external signal input providing the random voltages sampled. In addition to this, the Dual Ring Modulator also appears straightforward, with the only enhancements being the dual outputs from each, plus the ability to use the modulators in series or in parallel. Much more interesting than either of these is the Dual Waveshaper, a signal clipper that allows you to 'square off' signals, or invert and add the clipped portion back to the signal. The harmonic possibilities of this are huge, especially since you can use a CV to modulate the clipping threshold. This, like the Octal Subharmonic Oscillator, is a module that I'm just itching to play with. And there are more to come (see the 'And Here Tomorrow' box).

...And Here Tomorrow

If the three modules mentioned in the 'Here Today..' box extend the Selector's current somewhat limited fare, the future holds even more unorthodox promise. VCF1 is the primary missing link in the Selector's sonic palette. This will be similar to VCF2, but offer an 18dB/octave option and the classic 24dB/octave filter characteristic that makes vintage Moogs and ARPs sound, well, like vintage Moogs and ARPs. In addition to this, a Frequency Shifter will offer several sum and difference modes, and no fewer than four frequency modulation inputs. This should prove to be a source of many esoteric sounds. Next, a Voltage Controlled 'Morphing' Filter will offer the same four filter modes as VCF2, but allow you to apply a CV to 'morph' any mode into any other. With six independent outputs and a host of options including voltage‑controlled resonance, this promises to be one of the most powerful modules in the Selector range. Technosaurus are also promising a multi‑channel MIDI‑to‑CV convertor that will make the Selector up to 8‑note polyphonic. But perhaps most important of all, a 'pot pourri' module will add slew/portamento, level‑shifting, an invertor, and possibly an independent mixer to fill the gaps in the existing range.


The following prices include import duty into the UK and VAT, but not carriage, which will depend on the size of the system bought. Custom systems and build‑to‑order cases are available; contact Music Control for details and prices.

A £409
A (rackmount) £539
B £549
B (rackmount) £719
C £949
D £1619
VCO £199
VCF2 £199
VCA £149
Dual Envelope Generator £199
LFO/Noise Generator £149
Triple Resonator £259
Dual Ring Modulator £149
Dual Waveshaper £149
S&H/Random £149
MIDI Controller £339
DIN Sync/Clock upgrade for MIDI interface £89
Octal Subharmonic Oscillator £259
'Pot Pourri' Audio Toolkit £TBA
Frequency Shifter £TBA
VC Morphing Filter £TBA
Polyphonic MIDI Interface £TBA
System A £2049
System B £2099
System C £3899
System D £7099


  • It's big and it's sexy.
  • The sound quality is unsurpassed.
  • While limited in some ways, it still offers a huge range of sonic possibilities.
  • Reliable quarter‑inch patching.
  • Except for the VCA, everything is designed using discrete circuitry.


  • It's big and it's... very big.
  • Some of the current limitations are very limiting.
  • Many of those sonic possibilities still lie in the future.
  • Ouch, the cost, the cost!


The Technosaurus is a 'musical' synthesizer rather than an esoteric piece of laboratory equipment, and it sounds superb. Shamelessly expensive, it will eventually host a bizarre range of modules, so it may well prove to be the millionaires' modular synth of choice. But if the promised modules don't appear and there are too few wealthy customers to sustain its development, the Selector may prove to be a Swiss Miss.