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Analogue Systems RS200 & System 8000

Analogue Sequencer & Modular Synthesizer By Chris Carter
Published January 1999

Analogue Systems System 8000 modular synth.System 8000 modular synth.

Analogue Systems have expanded their RS Integrator modular range to include an analogue step sequencer and several new modules — as well as a new, complete high-end system.

When I reviewed the Analogue Systems RS Integrator modular synth in SOS June 1998, I mentioned that further modules and systems were in development — and six months down the line, up pop a new sequencer, a handful of new modules and a repackaged, more upmarket version of the RS Integrator itself, the System 8000.

As Easy As ABC

I'll come to the System 8000 in a minute, after I've described the RS200 Analogue Step Sequencer. This is a non-MIDI, 3-channel, 8-step sequencer, 72 HP units wide and designed to slot into the current standard Analogue Systems 19-inch case, while still leaving room for a couple of additional modules (more on this later). The RS200 design is based on the earlier Analogue Systems TH48 sequencer, a 3-channel, 16-step, self-contained free-standing unit (reviewed SOS April 1995).

As I mentioned, the RS200 has three channels, A, B and C, with individual controls for each of the eight steps and a stepped range knob for adjusting the overall output voltage of each channel (0V to +10V). Channel C also has a Slew control for smoothing the output voltage, or introducing a portamento effect if used with a VCO. In addition to a step indicator LED, each channel also has two toggle switches. One is a three-way Skip/Off/Reset switch which respectively skips selected events, does nothing, and resets the pattern back to the beginning at a specified step.

One Step At A Time

The other switch (Trig1/Off/Trig2) is a three-way trigger gate pulse output selector. Rather than the usual method of using a trigger output for each channel, there are instead two switchable trigger outputs (either trigger 1 or 2) for each step, and a third gate pulse that's activated at each step regardless of the trigger output switches. There is also a separate End Pulse output that triggers on the last step of a sequence. Not having three individual and simultaneous channel triggers could be thought of as restrictive, but switchable triggers do allow for some interesting rhythmic variations — a case of swings and roundabouts, I suppose. The internal clock (LFO) has a range specified as 0.01Hz to 30Hz (though the model I tested seemed to range only from about one step every seven seconds to all eight steps in half a second or so) and can be voltage controlled. An external clock, LFO, VCO or 10V trigger source can also be used to drive the sequencer.

Skip A Dee Doo Dah

An unusual feature I haven't seen before on an analogue sequencer is the Skip In socket. This is described by Analogue Systems as an 'experimental socket', to be used in conjunction with the Skip/Off/Reset switches and, as I discovered, it allows some interesting if sometimes unpredictable results. For example, sending the output of the sequencer's internal clock to a frequency divider and putting all the switches to Skip, then feeding the divided signal into the Skip In socket causes a sequence to play, then pause at a step, play again then pause at the next step, and so on... Feeding a noise source into the Skip In, by contrast, introduces a random element into the playback speed, and I found that using a random sample and hold voltage can even cause the sequence to step backwards. Skip In is a very useful and unique feature, and I'm sure many users will find all kind of creative uses and abuses for it.

Lastly, a Step button allows you to shift the sequence along one step at a time, while the Start/Stop button and Start/Stop input socket allow you to trigger playback from the front panel or an external source.

Analogue Systems RS200 sequencerAnalogue Systems RS200 sequencer

Standing Alone

The RS200 sequencer is also available as a stand-alone package in an RS10 3U case and with two additional modules, the RS150 Sequential Switcher and the RS260 Voltage Quantiser. The RS150 is a basic 4-into-1 pulse- (or clock-) driven sequential switcher. Each of the inputs can accept audio or control voltage signals, which can be selected sequentially using a control signal fed into the Clock Input socket, or by flicking the Stop/Step toggle switch. Another toggle switch sets the number of active inputs (2, 3 or 4) which then appear at the switcher output socket one after another.

Free Run

The RS260 module is a single-channel quantiser with a range of approximately five octaves. It responds to changes at either of the two V-In sockets, and at each detected voltage change transmits a new quantised voltage (0-5V) and a separate gate pulse (+10V). The controls are kept to a minimum, with just an output Offset knob for tuning and a Free Run/Ext Gate toggle switch. With the switch set to Gate In, the quantiser shifts to a new output voltage only if a separate gate/trigger is detected. If it's set to Free Run mode, the quantiser shifts to a new quantised output only if it detects a change in voltage at either of the CV inputs. Having two mixable CV inputs gives rise to some unusual glissando effects if, for instance, two waveforms such as a triangle or sawtooth waves are used at different speeds. A third CV input is also available, the Trans In socket. Connecting a CV keyboard output to this socket allows you to transpose the quantised output over a five-octave scale, a useful feature if the module is being used to quantise the output of the analogue sequencer. The Quantiser is an indispensable module with or without the sequencer, but its main use is faster and more accurate setting up of the unquantised sequencer outputs.

The RS150 Sequential Switcher is also a versatile module in its own right (almost a mini sequencer), but when used with the RS200 it definitely makes the sum greater than the parts. One feature lacking in the RS200 is the ability to run the channels in series, to get 16- or 24-step sequences. However, by sending each of the three sequencer channels into three of the RS150 switcher inputs, you can use the sequencer End Pulse output to step the switcher clock through the sequencer channels, giving you 8-, 16- or 24-step sequences at the flick of a switch.

Smart Choice

It's a shame that, unlike its earlier TH48 incarnation, the RS200 is only an 8-step sequencer, and that it's CV outputs are unquantised; I also missed not having a variable gate time control, although you could use the RS50 Trigger Shaper module for that purpose.

As with most analogue sequencers, however, using the RS200 is a doddle, and although adding the additional modules makes programming a little more complex you do have a seriously versatile unit. The basic RS200 module is very good value and the build quality is particularly high. Even though the stand-alone package with sequencer, quantiser, switcher, case and all costs substantially more, I still think it's still a fairly reasonable price for such pro piece of analogue kit. If you are a user of Analogue Systems modular synths (or Doepfer modules) and you don't yet have an analogue sequencer the RS200 is going to be a very smart choice.

RS System 8000

The RS System 8000 is an expanded and repackaged version of the original RS Integrator reviewed in the June 1998 issue of SOS. However, this isn't just any old cobbling together of a few new modules into a couple of 19-inch Euro-racks: this is something quite special and very professional, with a price to match.

The System 8000 is housed in a substantial, beautifully crafted, solid walnut cabinet measuring approximately 15 x 18 x 27 inches and weighing in at a very hefty 19.5kg — quite a beast. The cabinet contains four RS10 3U racks (without the rackmount ears), 29 RS modules and a rear panel with a power connector, power switch and 10 jack sockets internally hard-wired to a new Trunk Line module at the front (see Modules box, page 182). The lower half of the cabinet is angled at about 30 degrees towards the user. With a deep 5-inch walnut base to position a keyboard in front of, it has faint echoes of a bloated EMS VCS3. The majority of the System 8000 modules are as in the RS Integrator but here are details of the new ones.

RS130 Programmable Scale Generator

The major new module is the RS130 Programmable Scale Generator (PSG), a more sophisticated, slightly esoteric version of the RS260 Quantiser module I described earlier. Although this is one of the largest RS modules (18HP wide) the layout is minimal, with the main controls and input/output sockets the same on as the RS260 module, but with additional buttons for Mode, Save and Record, and a 2-line, 32-digit backlit LCD to display the notes being played. The module can be used in one of 6 modes, the default being Quantiser — in which it functions in exactly the same way as the the RS260 Quantiser module. The other modes are dedicated to converting analogue control voltages into 1V/octave tempered scales: C Major Scale, C Minor Scale, C Major Arp, C Minor Arp and User Memory. When in these non-quantiser modes, any detected changes in control voltage at either of the V-IN sockets are converted into a tempered scale. For example, if the PSG CV output is connected to a VCO, any LFO waveforms fed into the PSG become chromatic arpeggios and glissandos in either major or minor scales. In a similar way, normally random voltages from a Sample and Hold module will always play in a musically relevant scale.

Taking this concept one step further, the User mode allows one to program notes or scales of your own (up to approximately 60 notes), which is a very simple procedure. While in Quantiser mode press Record and hit a key on your CV keyboard (whose note and MIDI number appear in the LCD), then press Record again. This enters the note for step one — continue entering notes (pressing Record after each) until you have the scale of your choice, then press Save and that's it. The User memory mode will now play only the notes you've entered, regardless of the input source. Trying to use a scale entered in User mode initially caused me a fair bit of head-scratching, as inputting a slow LFO wave or playing keyboard notes higher or lower than those entered resulted in silence. The snag is that new notes are only output by the PSG if the input voltage is inside the range of the notes you have programmed. So, for instance, if only Cs are entered over four octaves (48, 60, 72, 84) and an LFO wave is outputting a full 0-10V waveform, the extreme highs and lows of the wave won't be output, so there will be some long and awkward pauses.

But all this aside, this is still a very useful module, and akin to a basic (very basic) digital-cum-analogue step sequencer. Some of the most fun, and some incredibly complex-sounding arpeggios, can be had when feeding two different CV signals into the V-IN inputs, such as fast and slow LFOs, ADSR and LFO, sequencer and LFO, S/H and LFO — in fact the combinations are endless. The PSG (or multiple PSGs) would also work well in a live situation, and could allow for some great improvisational setups while staying within predetermined or programmed musical parameters.

RS170 Divider

This module will take a signal or waveform and produce four square wave sub-octave signals from it. The octaves are fixed, with independent divided outputs: ÷2, ÷4, ÷8 and ÷16, and a fifth undivided square wave signal derived from the original signal. There are no controls, just a single monophonic input and five outputs, each with an activity LED. The Divider will accept control, gate, trigger or audio signals, and is useful for dividing sequencer clocks or for adding more bottom end to VCO audio signals.

RS120 Comb Filter

This is, in essence, a mono analogue delay line able to simulate a phaser, flanger chorus and very short echo effects. As with other RS filters there are two CV inputs, two audio inputs, a resonance control and, in this case, a Delay Time knob instead of the usual frequency control. The delay time is variable from 2.5mS to 25mS using the Delay knob or a control voltage, and at extreme delay settings you can even hear an authentic-sounding high-frequency clock noise breaking through. Nevertheless, effected audio signals sounded fine, and suitably analogue — just don't expect 16-bit digital quality. Actually, I had forgotten how good an analogue delay line can sound, especially a voltage-controlled one. Unusually, the module can also accommodate control signals such as triggers and gates through its signal inputs, a feature worthy of hours of experimentation.

RS250 Trunk Line

This is a basic, passive 10-way patchbay for converting front panel-mounted mini-jack sockets to rear-mounted quarter-inch jack sockets. This useful module allows you to have all manner of external units (mixer channels, effects, synths and so on) connected and available within the System 8000's front panel environment.

RS270 Adaptor/Converter

This passive module has four independent channels, which all convert mini-jack to quarter-inch jack sockets; two channels also include phono sockets. An indispensable module for interfacing with the outside world.


Thus far, Analogue Systems haven't enjoyed the high profile of the similarly specified Doepfer range, but hopefully these new modules and the walnut System 8000 will start to redress the balance. The new-look cabinet may not be particularly functional or portable, and is not exactly low cost, but is a vast stylistic improvement on the current 19-inch Euro-rack and puts the System 8000 into a different league. While this system will appeal mainly to pro analogue musicians, studios out to impress clients and serious collectors of quality analogue systems, it's still within the reach of us lowly struggling musicians, as every part can be purchased individually — even the walnut cabinet.

For the first time in almost 20 years, I think I've actually found in the System 8000 a contemporary analogue modular system that I would seriously consider as a replacement for my beloved but rapidly ageing Roland System 100M (although I'm hoping my 100M won't go to silicon heaven for at least a few more years yet). My advice: if you can afford it, invest in a System 8000; if you can't, start saving.

And You Thought This Was Big?

According to Bob Williams at Analogue Systems, the System 8000 cabinets are "only the babies..." Apparently, they are also used merely as the outer wings of a monster modular system called Phoenix. The Phoenix has four cabinets (the centre ones being 38 inches wide) and in excess of 200 modules. At present, only a couple of Phoenix systems are in existence — one resides at the Synthesizer Museum in Hertfordshire, and another is due to make an appearance at the Frankfurt show in February 1999, containing some juicy new RS modules to boot.

What with Doepfer offering multi-module interpretations of classic modular systems and the frighteningly enormous Technosaurus mega modular synth also available (SOS review coming soon), the analogue modular market is beginning to look like a case of who can outdo whom in a mine-is-bigger-than-yours race. Mind you, if I won the lottery I'd be first in line with my cheque book!

Modules And Prices

The prices given below are Analogue Systems' recommended prices.

  • Stand-alone RS200 sequencer package (includes cabinet and modules listed below) £649.
  • RS10 3U 19" case and PSU £185.
  • RS200 Analogue step sequencer £325.
  • RS260 Quantiser £95.
  • RS150 Sequential switcher £55.
  • System 8000 (complete system including walnut cabinet and modules listed below) £2200.
  • Walnut cabinet only £700.
  • RS20 Ring mod/multiples £45.
  • RS30 Pitch to voltage and envelope follower £45.
  • RS40 Noise, sample and hold, & clock £60.
  • RS50 Trigger generator with VC pulse shaper £55.
  • RS60 VC ADSR £65 (x3 in System 8000).
  • RS70 Preamp, inverter, slew £55.
  • RS80 VC LFO £65 (x2).
  • RS90 VCO £65 (x3).
  • RS100 Low-pass VCF £65.
  • RS110 Multi-mode £65.
  • RS120 Comb filter (phaser/flanger) £65.
  • RS130 Programmable scale generator £325.
  • RS160 Linear/logarithmic 4-1 Mixer £32 (x3).
  • RS170 Dual 5-way multiples £17.
  • RS180 VCA £45 (x3).
  • RS230 Dual CV buffer £35.
  • RS250 Trunk line £17.
  • RS270 Dual adaptor/converter £32.
  • RS280 Audio and trigger clock divider £60.

See SOS June 1998 for a list of previous modules and prices. All prices include VAT.


  • Versatile and relatively easy to use.
  • Some unique features.
  • Excellent build quality.
  • Available as a stand-alone unit or module by module.
  • Reasonably priced.


  • Only 8 steps per channel.
  • Channels can only be chained in series using the RS150 module.
  • No control of gate output width.
  • Unusual Trigger output configuration.


A versatile, well equipped, non-MIDI analogue sequencer. It may lack some features of its earlier incarnation (the TH48) but then again it includes a few unique features of its own. A quality sequencer at an acceptable price.


See 'Modules And Prices' box.

Analogue Systems +44 (0)1726 76785.