WHAT’S SO SPECIAL ABOUT ANALOGUE SYNTHS?
Getting into analogue synthesis for the first time? Our quick guide will get you up and running in no time!
Much like vinyl, ‘analogue’ technology is held in high esteem, but debate rages around the realities of its lauded properties. More than 50 years after the first mass market analogue synthesiser hit the market, their basic format is more widespread than ever.
Do analogue synths really sound better? What makes this theoretically outdated tech remain so popular in the supposedly forward-thinking realm of electronic music making?
This issue we’ll be exploring the realities of ‘analogue’ gear: why it inspires such love in its fans, how it’s evolved and – crucially – how to use, set up and sequence using analogue principles.
As we’ve discussed in these pages previously (see FM373) there are certain things that only software and digital synthesisers can do, such as complex frequency modulation, granular or wave-table synthesis. In theory at least, there’s little an analogue synth can do that can’t be replicated in the digital realm. Countless virtual analogue instruments offer exact replicas of classic synth engines, often offering extra convenience through increased voice counts, full parameter recall and – in hardware – a more convenient form factor. So why would anybody want to bother with an analogue synth?
The reality, of course, isn’t quite so simple. Analogue synths are still prized by a multitude of electronic musicians. In fact, with the rise of affordable analogue instruments and Eurorack modular synthesis has meant that true analogue synths have become considerably more accessible and widespread over the past decade.
We put the question of analogue’s longevity to synth designer/aficionado Tom Carpenter, of UK brand Analogue Solutions. “Imagine painting a picture, but your easel is at the end of a long hallway and you have to manipulate the brush from outside, via the letterbox, using some very long tweezers,” he explains, when asked about his adversity to software synths. “Many physical digital hardware synths aren’t much better either. For me, if I have to go even one layer down in a menu then that’s me done.”
This physicality is something that is regularly cited as a primary draw of
analogue synths. While digital hardware, obviously, also offers an element of hands-on interactivity, the tacticity of adjusting knobs and faders on a voltage-controlled instrument can be difficult to emulate. This becomes ever more true in the semi-modular and modular realms, where physically patching control voltages (CV) provides not only hands-on interaction, but an element of unpredictability. CV signals can create ‘happy accidents’ in a way unlikely to happen in digital synths.
When it comes to analogue synth design, few can match the career of Dave Smith. His original Sequential Circuits brand was responsible for some of the most influential instruments of the ’70s and ’80s, such as the Pro One and Prophet-5, and since re-entering the market with Dave Smith Instruments in 2005
(now once again renamed Sequential) he’s also created some of the most lauded synths of the 21st century. For him, the draw of analogue all comes down to the sonics.
“They sound better!” he tells us. “I continually have artists telling me how good they sound. They are also much more fun and interactive to play; they feel like a musical instrument should. I could talk about all the subtleties of analogue circuitry, but just use your ears.”
While Analogue Solutions have, as the brand name suggests, stuck fairly rigidly to analogue circuitry in the design of their synths, Smith’s DSI and Sequential brands have dabbled in digital technology on a number of occasions. In the late-’00s Dave Smith Instruments began equipping synths with DCOs – digitally controlled oscillators that offered analogue sound with more stable tuning. The more recent Prophet-6 goes further with the inclusion of a full wavetable oscillator and digital synth engine. We asked Smith if he now believes there’s a perfect ‘middle ground’ where digital elements can sit alongside analogue.
“Certainly. Technology has come a long way since I designed the Prophet-5 in 1977,” he explains.
“We take advantage of that. The sweet spot depends on the instrument design. Sometimes we use a digital oscillator or wavetable oscillator, sometimes VCOs, sometimes a mix. The most critical part is the filter; we always use analogue filters. Other controls like modulation, LFOs, and envelopes are best done digitally these days, for many reasons.”
FALL AND RISE
The consensus on analogue synths hasn’t been a constant over the past 50 years though, as another synth design icon, Tom Oberheim, explained to us in 2019. “Dave Smith’s Sequential Circuits went under in 1986 and by then I knew Roger Linn really well and his first company went under. Everything was turning digital. The Yamaha DX7 started the digital revolution in 1983 and then there was the Korg M1 and the Roland D50, so analogue became pretty much dead.
“It became a different world, people wanted perfect strings, perfect brass and a Fender Rhodes that didn’t weigh 200 pounds.”
Oberheim credits modern dance music and the Eurorack community as the biggest promoters of the analogue revival. “Two things happened when the new century arrived. Dave Smith got back in the business in 2005, but the other thing was this growing monster called Eurorack. Thanks to the dance crowd and the Eurorack crowd, analogue is back and better than ever. It was a bumpy ride for someone like me who had been so involved. I was the second generation – the first generation was Bob Moog and Donald Buchla, but here we are and the synths are back thanks largely to the dance producer folks.”
From a designer’s point of view, how does the process of creating analogue instruments differ now compared to the ’70s? “Generally designing is easier since the design tools are so much better now,” Smith tells us. “Some old components have been brought back, like the Curtis parts made by OnChip, Doug’s company, used in the Prophet-5. Other parts are hard or impossible to find, so we find alternate parts with the same analogue flavour.”
Tom Carpenter also sees positives in comparison to when he formed Analogue Solutions in the mid-’90s. “It’s easier in one sense – I now have 25+ years experience, and remember this doesn’t just cover synth design but also running a business and manufacturing. It takes knowledge of sheet metal, printing, packaging. Also shipping, tax laws and all aspects of running a business. But that 25 years+ means that each product evolves as I do, adding more adventurous features.”
For many reasons though, both designers flag how tough the current climate is. “It is getting harder,” Carpenter tells us. “The main reason is skyrocketing costs due to inflation and the global supply issues.”
“In the last year, all ICs are hard to find and costs are going way up,” Smith explains.
FAKE IT TIL YOU MAKE IT
How does the threat look from the digital front? Are emulations close to eclipsing the need for authentic circuitry? Even ardent believer Tom Carpenter admits they’ve come a long way. “Many sound ‘the same’ in a blind test. Does it matter what instrument is used as long as the song is good? Perhaps not.”
The lure of analogue is not dead though. “Personally, I get no joy from using a fake,” he tells us. “A ‘clone’ of a synth is not the original.”
Dave Smith is more dismissive. “I haven’t tried any in many years,” he tells us. “I’m guessing they have improved, though for me it’s about look and feel. I’d much rather be in front of a hardware synth with a set of knobs that never change or move. It’s all about interacting with a real musical instrument.”
“THANKS TO EURORACK, ANALOGUE IS BACK AND BETTER THAN EVER”
MONOSYNTH/POLYSYNTH
Monosynth/Polysynth refers to how many voices a synth has, ie, how many notes/pitches it can generate simultaneously. A monosynth is only capable of generating a single note at any one time. A polysynth can simultaneously produce multiple pitches in accordance with how many voices it offers. This allows it to create a polyphonic output
– ie, chords.
MODULAR/SEMI-MODULAR
Modular/semi-modular are types of synthesiser that can be rerouted by the user. Typical self-contained synthesisers – a Minimoog, for example – are pre-wired, so the connection between its oscillators, filters, amps, etc cannot be changed by the user. A modular synth is made up of totally distinct elements – aka modules – each of which usually specialises in a specific role, such as a filter, oscillator or envelope. In modular systems these could come from a variety of different brands, and can be freely swapped and connected by the user. A semi-modular synth is a middle ground between the two – it is a self-contained instrument, and will usually create sound without the need for user-created connections, but its elements can be reconfigured or connected to external gear. This is done through the inclusion of a patchbay – a selection of individual inputs and outputs available at various points in the synth’s signal path.
EURORACK
Eurorack is a standard of modular synthesis invented by Dieter Doepfer. This standard, which has now been widely adopted by most modular brands, set guidelines of how much voltage modules could receive, the overall size of the gear, the power requirements, and jack sizes for receiving and sending voltage/audio/etc.
CV
CV stands for “control voltage”. It’s a fundamental tool for sending essentially analogue “information” from one source to another. CV can be notes in a scale, triggers for turning events on and off, modulation, and more! In the Eurorack realm (or most semi-modular synths), each octave in a scale is represented by 1 volt of electricity. So if you write a 2 octave arpeggio, it will span 2 volts of electricity.
TRIGGER/GATE
Trigger/Gate is a type of CV that signals an event to be “activated”. If you’ve played a synthesiser keyboard, every time you press down on a note, you’re creating a trigger event in the keyboard to activate that particular note. Gates are used to trigger all sorts of events in modular gear, from notes in a sequencer, starting LFOs, signaling stages of envelopes, and more. In terms of actual voltage, gates usually represent either low voltage or high voltage, creating a binary on/ off scenario.
MODULATION
Modulation is when the input of one parameter is adjusted
(over time) from the output of another. In the analogue/modular world this is done using CV. Synthesis is built on modulation. Sources getting adjusted from other sources is probably the simplest way of describing synthesis, and you (the synthesist) are the ultimate modulator.
VCO
VCO stands for “Voltage Controlled Oscillator” and can also just mean oscillator in the analogue world, or osc for short. The VCO is a building block for sound generation because it literally self-oscillates continuously while it is powered on. The VCO will accept a CV for pitch control. In terms of Eurorack, it’ll be 1 volt per Octave. Most VCOs output multiple waveforms. The most basic is a Sine, Triangle and Square wave. Most VCOs offer at least these fundamental shapes for synthesis.
DCO
DCO stands for “Digitally Controlled Oscillator”. This is essentially the same as a VCO, and still produces analogue sound, but is controlled by a digital input, rather than via CV, for more stable tuning.
VCF
VCF stands for “Voltage Controlled Filter” and is the most common element or module for shaping
sounds. Filters work by cutting frequencies from a signal. There are a few fundamental types of Filters. The most common is…
LPF
LPF which stands for “Low-Pass Filter”. This type of VCF will allow any frequencies below a certain level to pass through the signal to be heard. Frequencies above the filter cutoff point will gradually be filtered out of the signal.
HPF
HPF stands for “High-Pass Filter”. This type of VCF is just like the LPF, but in reverse. Frequencies above the cutoff point will pass through and be heard. Meanwhile frequencies below will be filtered out.
BPF
BPF stands for “Band-Pass Filter”. This VCF allows a narrow band of frequencies to pass through the signal, filtering out the frequencies above and below the cutoff.
NOTCH
Notch Filter is the last type of VCF and probably the least common. It’s usually used in traditional equalizers, but can occasionally show up in VCFs. It basically does the opposite of the BPF, by rejecting any frequencies from the signal at the cutoff point.
ENVELOPE
An Envelope is a contoured CV. It’s typically broken up into multiple sections that define its “shape”.
These sections typically include attack, decay, sustain, and release. All four of these sections can shape fast plucky sounds, to soft gentle pads. Some envelopes are even simpler with just an attack and decay setting. Some envelopes can trigger a gate event after each phase of the shape. For instance, once the attack part is complete, a gate can be triggered to signify that portion of the envelope is complete and trigger another envelope to start for a modulation source.
VCA
VCA stands for “Voltage Controlled Amplifier” and is often paired with an envelope. VCAs take a CV, usually from an envelope, and amplify a signal with the contour of the CV. Most synthesisers have a VCA at the end of the signal chain to finalise the shape of the sound. VCAs can be used to shape modulation sources, in conjunction with envelopes, to create complex modulations.
LFO
LFO stands for “Low Frequency Oscillator” and is the most common source of modulation. Most basic synthesisers come with at least one LFO to help create moving sounds. Basic LFOs usually have a sine or triangle wave shape, and a square wave to patch out. Some can be synced with a gate to start the LFO each time a gate trigger is received.
Good quality VCOs can also double as LFOs, assuming their tuning can go low enough.
SUBTRACTIVE
Subtractive Synthesis is the process of subtracting frequencies from a signal, usually with a VCF, to create a new signal. Combining multiple VCO and then patching a VCF to “subtract” some harmonics is by nature Subtractive Synthesis.
FM
FM Synthesis stands for Frequency Modulation Synthesis. This process involves taking one VCO and modulating its signal with another VCO, or other complex CV signals. This can also create harsh, metallic