Jim Aikin reviews the Spawn, a rackmount analog synth module from Analogue Systems. The Spawn combines patch-cord versatility with MIDI capabilities, including integrated MIDI-to-CV conversion.
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Jim Aikin reviews the Spawn, a rackmount analog synth module from Analogue Systems. The Spawn combines patch-cord versatility with MIDI capabilities, including integrated MIDI-to-CV conversion.

analog synthesizer
FEATURES3.0EASE OFUSE4.0QUALITY OFSOUNDS3.5VALUE3.5RATING PRODUCTS FROM 1 TO5PROS: Real analog sound.Very patchable, but useful default routings require no patching. Makesa good MIDI interface/expander for any analog synth system, yet fullyfunctional as a standalone unit.CONS: No memory. Only oneoscillator and one envelope generator. MIDI channel selector is on rearpanel.ManufacturerAnalogue Systems/Sweet Noise(distributor)
tel. (818) 980-6983
Web or www.sweetnoise.comSpawnSpecifications
SoundEngineanalogsubtractive synthesisSynthesisArchitectureVCO, resonantlowpass VCF, VCA, ADSR EG, voltage-controlled LFO, noise generator,modulation VCAAnalogOutputs(1) ¼"monaural main out; (12) ⅛" audio and CV outputs in analogsections; (10) CV outs in MIDI Routing sectionAnalogInputs(15) ⅛"audio and CVControlVoltage Standard1V peroctaveMIDI-to-CVConversiongate (single ormultiple triggering), trigger, S-trig, key played (×2), Velocity,Aftertouch, mod wheel, breath controller, expressioncontrollerPower100-120V, 60 Hzor 220-240V, 50 Hz (switchable); IEC connectorDimensions2U × 8"(D)Weight6lb.PRODUCTSUMMARYAnalogue Systems
analog synthesizer

Analog synthesis is hotter than ever. It was eclipsed in the '80sand '90s by digital technologies, but it never really went away. Today,as many as a dozen companies are building high-quality analoginstruments for a small but enthusiastic market, and almost everydigital-synth designer is trying to duplicate the analog sound usingDSP software.

Real analog synths tend to be pricier than their digital cousins,primarily because of the cost of components and construction. Butthere's something about the sound and playability of real analoginstruments that keeps musicians from carping about the expense. Maybeit's the warmth and fatness of the tone. Maybe it's the smooth responseof the knobs when you twist them. Or maybe it's the same gut feelingguitarists get from handling a '57 Stratocaster.

The most tactile electronic instrument you can buy is a patchableanalog modular synth. Those beasts, which are still designed much asthey were in the mid-'60s, bring audio and control signal routings outto the front panel. By plugging patch cords into jacks in the panel,you can massage or mangle the sound in complex ways, looking every bitthe mad scientist. Trouble is, a full-bore modular synth is both bulkyand expensive. Consequently, there's a real need for analog synths thatare smaller and more affordable, yet preserve some of the patchablepower of a modular.

Enter the Spawn. This 2U rackmount analog synth is built by AnalogueSystems, a respected British manufacturer of modular synthesizers. TheSpawn works well as an expander module for a larger system fromAnalogue Systems or any other manufacturer that uses the 1V-per-octavestandard. Even if you don't have any analog gear, you can play it fromany MIDI keyboard, making it an ideal source for bass and lead soundsin a studio or live rig.

To help me test the Spawn's patching features, Analogue Systems senta separate rackmount unit containing half a dozen of the newer modulesin its Integrator line. I especially enjoyed trying out the Comb Filterand the EMS Synthi Trapezoid Generator. The company also supplied aFrench Connection analog keyboard controller, which has some unique anduseful features (see the sidebar “The French Connection”),and a big pile of patch cords. Before long, my studio was SpaghettiCentral.


The Spawn contains the basic modules you need to make synth noises:an oscillator, a resonant lowpass filter, an ADSR generator, an LFO, anoise generator, and two VCAs. Unlike an Integrator, the Spawn is apreconfigured system; you can't order it with a custom set of modules.The front panel features 23 knobs, 37 minijacks, and a few switches(see Fig. 1). The knobs feel comfortingly solid, with a littleresistance and a rubbery texture that makes them a pleasure totouch.

Rather like the ARP 2600, the Spawn doesn't require that you usepatch cords to set up a sound. Its modules are wired to one anotherbehind the panel with a default signal flow. The main ¼-inch audiooutput is on the rear panel, along with MIDI In and Thru jacks, astandard AC power-cord connection, the power switch, and a little slotwith which you set the MIDI channel (see Fig. 2). Having thepower switch on the rear panel of a rackmount unit is less than ideal,but changing MIDI channels from the rear panel — with ascrewdriver, no less — is downright primitive.

Except for MIDI reception, the Spawn is an all-analog device. It hasno operating system, and thus no hidden menus. It offers no patchmemory. If you like, you can think of its panel as WYSIWYG (what yousee is what you get). The fact that you can neither store your favoriteprograms nor dial up factory presets has a good side and a bad side.The good side is that you'll quickly become an expert at Spawnprogramming. The bad side is that until you do, getting back thatkiller bass sound you had yesterday may be quite difficult. The manualcontains some blank patch sheets on which you can write down the knobsettings and patch-cord routings for sounds you discover, but a patchsheet can only get you into the ballpark. Nudging the knobs is stillrequired.


The Spawn's voltage-controlled oscillator has a rich, satisfyingsound. Although the Spawn has only one oscillator, it has asuboscillator output that produces a square wave that's either one ortwo octaves below the main tone. The VCO and sub have separate levelcontrols at the filter's input, so you can mix them to taste.

The VCO's waveform is continuously variable from sawtooth to squareto thin pulse. It has no sine- or triangle-wave output, but you canfake either of those waveforms by filtering the square wave. You canapply waveform modulation (such as pulse-width modulation) without apatch cord using a bidirectional Mod knob; turning it left of centeradds modulation from the LFO's triangle wave, and turning it right addsmodulation from the envelope generator (EG).

Tuning of the VCO is handled with a single knob and a three-positionswitch labeled -2/0/W. The -2 and 0 settings are octave selectors, andW means wide. When the switch is in the left or center position,the knob has a range of just over an octave in each direction. When Wis selected, the knob sweeps the frequency from subaudio to sounds onlyyour dog can hear. You can modulate pitch with the LFO using anotherbidirectional knob; turning it left gives you triangle-wave modulation(for vibrato), and turning it right yields square-wave modulation.

The Spawn VCO's tuning was stable, and it tracked the keyboardadequately across several octaves. (However, that was not the case withthe external VCO in the Integrator rack Analogue Systems sent me; whentuned correctly to a low C, the Integrator was almost a half step sharpwhen I played the C four octaves up.)

Along the bottom of the VCO module are three input jacks, each withits own knob. One jack is for a 1V-per-octave signal from an analogkeyboard; its associated knob controls Glide rate. The second input isfor pitch modulation (from the envelope or an external module, forinstance), and the third is for waveshape modulation. The Amount knobsfor these two jacks are bidirectional.

In the VCO section's center, a row of minijacks provides someimportant functionality. Applying a rising-edge voltage to the Sync Injack causes the VCO to start a new wave cycle, enabling hard-synceffects if you have a second VCO lying around. Four jacks in the middleprovide access to a separate Mod (modulation) VCA, with which you canset up such effects as mod-wheel control over LFO amount. A VCO Outjack permits flexible routing options.

I like the sound of the Spawn's VCO; it is smooth, with lots ofpresence. All the same, having only one oscillator is a definitelimitation, because many of the richer sounds in the analog world arecreated by detuning two oscillators from one another.


The VCF is strictly lowpass and always operates with a 24dB-per-octave slope. It will squeal very satisfactorily at highresonance settings. Its tone was a little cleaner and less beefy thansome analog filters I've heard, but I found I could fatten it up in atruly nasty way by cranking up the resonance and then applying theVCO's audio output to the filter's modulation input. It's tough to dothat kind of trick with most digital simulations of analog.

The filter has two bidirectional Amount knobs for controlling cutoffwith the LFO (triangle or square wave) and EG. The VCF also providesinputs and Amount knobs for a second audio signal and anothermodulation input. Four additional jacks are located in the middle:three provide outputs for the suboscillator, the noise source, and theVCF itself; the fourth is an unattenuated 1V-per-octave CV input,suitable for having the filter track the keyboard.

At the two o'clock position, the oscillator signal input level knobis labeled O/D, but the overdrive introduced was so subtle that I hadtrouble hearing it at all. The VCA's input from the filter has the samefeature — but again, after compensating for the added gainintroduced by cranking the knob all the way to 10, I wasn't entirelysure I heard any overdrive.


Experienced analog programmers might be concerned that the Spawn hasonly one ADSR generator, which has to do double duty controlling bothfilter cutoff and the VCA. How can it produce filter sweeps if the notealways fades out at the bottom of the sweep? Not to worry — theVCA's Envelope knob lets you choose either linear or logarithmiccontrol. By turning it in the linear direction, you get a goodfull-bodied sustain, even as the filter responds with a sweep duringthe decay. Of course, having only one envelope still presents somelimitations. For example, you can't specify a gentle VCA attack coupledwith a quick filter attack.

The EG has a three-position switch for choosing Gated Repeat, AutoRepeat, or normal ADSR mode. The repeat modes are useful for creatingtremolo effects, though you can obtain similar results by patching anLFO output into the EG's Trig (trigger) input jack.

The Spawn's LFO is modest and unassuming. It has simultaneousoutputs for square wave, triangle wave, and positive- andnegative-going sawtooth waves. You can set its Rate knob from about 0.2Hz up to 25 Hz or so. You can also control the LFO's rate with a CVinput, which is calibrated in a linear way rather than as 1V peroctave. Considering the rather spartan module lineup of the Spawn, Iwish the LFO could do double duty as a second audio oscillator, butgiven the limited range and the linear CV input, that's not anoption.


The awkwardness of the channel selection process notwithstanding,the Spawn's MIDI features will give it a strong appeal. Front-paneljacks offer MIDI-to-CV outputs for the keyboard's control signal (twojacks, in case you want both the filter and the oscillator to track thekeyboard), gate, Velocity, Aftertouch, the mod wheel or lever (CC1),breath controller (CC2), and expression controller (CC11). Two triggeroutputs are also available — one providing a rising edge and theother a falling edge (that's an S-trig, for you analog maniacs). Youcan choose single or multiple triggering, but the keyboard response isalways low-note priority.

With a switch labeled Internal/Isolated, you can detach the MIDIsignals from the internal synth. That function is extremely useful, asit lets you use the Spawn as a MIDI interface for the analog modules ofyour choice while keeping the MIDI data away from the Spawn's internaloperations.

In addition to the obvious internal routings (such as MIDI keyboardto pitch), the Spawn lets you route mod-wheel data to the oscillator'sMod VCA. Two patch cords are still required to patch the desiredmodulation source to that input and the VCA output to the oscillator'spitch-mod input (or wherever). Once you've set this up, though, yourMIDI keyboard's mod wheel will add vibrato.

The Spawn lacks a separate output for MIDI Pitch Bend data; instead,the keyboard control voltage tracks pitch bends, and bend depth isalways plus or minus 1 octave. Such a setup is handy in the sense thatit doesn't require you to use up the oscillator's pitch-mod input forbends, but the absence of control over the bend depth is rathertroublesome. Given that you can't adjust bend depth, I would havepreferred an interval of plus or minus a whole step, which is betterfor playing leads.


The Spawn's patchability makes it a great expander for any analogsynth system, especially one that uses minijacks. Its MIDI featuresmake it a good choice as a standalone bass or lead synth. Thesingle-oscillator sound isn't as meaty as I'd like, but routing theoutput through an outboard chorus or delay line will thicken it up. TheIntegrator Comb Filter module will also do the job, and with attitudeto spare.

Although analog purists certainly won't mind, busy studio playersmight be bothered by the fact that the Spawn has no memory for storingpatches, and that the knobs don't transmit or respond to MIDI data. Butthen, a violin doesn't have those features either. Like a violin, theSpawn is a real musical instrument. Some effort is required to play itwell, but the effort will pay off with a variety of expressive tonecolors.


The Spawn's MIDI features are robust enough that you may never needa real analog keyboard, but Analogue Systems' French Connectionkeyboard ($1,995) is still worth a look (see Fig. A). Inaddition to the spring-loaded joystick (very nice) and lack of Velocityresponse (not so nice), it has one feature you won't find on any MIDIkeyboard: mounted on a strip at the front of the keys is a finger-sizebrass ring that you can freely move from left to right across thekeyboard's almost four-octave range, thanks to a long piece of blackstring and an ingenious system of hidden wheels. By throwing a coupleof switches at the keyboard's left side, you can play monophonic linesusing this ring (and a left-hand thumb button for sending gates)instead of the keyboard. History buffs might recall that this type offinger-operated pitch controller was introduced in 1928 on anelectronic instrument from France called the Ondes Martenot (henceFrench in the name).

Nailing the precise pitches in an equal-tempered scale by moving thering takes practice, but the French Connection makes pitch control alittle easier by providing a row of raised and lowered bumps on a stripbeneath the ring. The bumps line up with the keys, giving you tactileas well as visual feedback. There's always some portamento (glide)between notes, but you can control the glide rate in expressive ways.Wiggling your finger gently back and forth produces vibrato directly,at a rate and depth that you can control intuitively to shape yourphrases. In the MIDI world, only the Clavia Nord Lead gives you suchdirect tactile control over vibrato.