Smelling Pretty Colours

Remember COVID? Remember how it was a joke, and then it wasn't a joke, and then it faded away, and then it came back worse? And then it ground on and continued and is still with us, but we've learned to accept that the world has changed, so it no longer has power over our minds. It can kill us, but it can't break us any more. Remember that?

During the early part of 2021 I built a modular synthesiser, and I still haven't grown tired of it. It was one of those if-not-now-then-when projects, but I hate waste, and some of the modules - Plaits in particular - are endlessly fascinating. My love is still strong.

After a lot of tinkering here's what it looks like now:

What's the point of a modular synthesiser? Partially the wealth of modulation options, and partially the fact that all of the controls are right there, in front of me. I don't have to assign controllers or remember that unlabelled knob X controls pulse width, I have the controls right there in front of me.

The tune at the top of this post is built entirely on a bassline made with Mutable Instruments's Plaits. It uses the two-operator FM model, and for twelve minutes I twiddled Plaits' knobs while an LFO also did some twiddling, as my little robot helper. The rest of the instruments are a mixture of simple synthesiser tones and an organ performed by my Korg Volca FM, plus Logic's Alchemy, and a bit of squelchy Behringer TD-3. The singing robot voice is also Plaits, but with one of the other models.

The main rhythmic idea was an accident. In the original demo, below, I set up the Volca FM's sequencer incorrectly, so that it cycled every seven notes instead of every eight notes:

The end result reminded me of Steve Reich's phasing experiments, so I replaced the original marimba sound with a buzzy electric organ, fed into the exciter section of the Joe Meek VC3 mentioned in the previous post. Because Steve Reich used electric organs. When I think of the New York minimalist avant-garde of the 1970s I think of electric organs. Buzzy electric organs, The result is a hypnotic groove that sounds as if it's rushing.

One day I will learn to program a second drumbeat. Not this day. And I think of Philip Glass driving a taxi, and Taxi Driver, and New York at night in the rain, and people living in warehouses, and you can never go back.

Doepfer LC1: Titania

Earlier in the month I had a look at the Doepfer LC1, a compact modular synthesiser case with 48hp of space for Eurorack modules:

48hp is just large enough to make a self-contained instrument, but unless you buy a load of modules from mini-modular maestros 2HP you have to make some hard choices. One oscillator and some modulation options? Two oscillators and no modulation? One envelope? Two? Do I really need a spring reverb?

To which the answer is yes, yes I really do need a spring reverb. Could I buy a third, even smaller case, just to house the spring reverb? Such as for example Doepfer's MC Mini Case, which is 32hp wide. But that way madness lies.

Apart from being sources of mental uncertainty smaller Eurorack cases are also useful as expansion boxes, and that's the topic of this brief post. The music at the top of the page was made with the following configuration of the LC1, plus a Behringer Model D, which I really need to dust off with a brush. And also a biscuit tin, because I couldn't see the monitor otherwise:

In this setup the LC1 houses a pair of Behringer 112 VCOs, plus some miscellaneous modules that provided moral support. I think I used the Doepfer A-166 a little bit, the other modules not at all. The oscillators are feeding into the Model D's external input, which is in turn feeding the sound through its own filter and envelopes. The end result is a MiniMoog clone with five oscillators, which is overkill - the MiniMoog was not known for sounding thin, the Model D likewise - but why not. All of the obvious synthesiser sounds, plus the SPROING! snare drum sound in the latter half, were made with this setup

The sproing snare drum sound was made with the Model D's oscillator modulation. It sounds exactly like a similar effect in Jean-Michel Jarre's "Calypso 2" and I wonder if he used a similar technique to make that effect, with whatever synthesisers where on Waiting for Cousteau (unusually, that album doesn't list his equipment).

Of course the track doesn't just use the setup above. There are some space effects, which are made with a cheap guitar delay pedal with the intensity control turned up so that it creates feedback. I was thinking of Tangerine Dream's early albums, when they only had a VCS3, and most of the synthesiser-style effects were made with organs and guitar pedals.

There's also masses of Mellotron, courtesy of GForce's M-Tron, which is by now twenty years old. Can a VST plugin be vintage? M-Tron is older now than most people on Reddit and by extension the internet as a whole. The latter half of the first movement uses GForce's Isolation Choir bank, which was recorded during the COVID lockdown. And of course Valhalla's Supermassive, a terrific and free reverb plug-in.

On a musical level I wanted to make something that was harrowing and relentless, because I was in a happy mood. It's inspired a little bit by Tangerine Dream's Alpha Centauri and "Thru Metamorphic Rock" from their much later album Force Majeure, and also by the colour black, and the thought of pencil lead and dry paper.

Doepfer LC1: Miniature Modular

Clowns to the left of me, jokers to the right, and earlier in the year I built a modular synthesiser. Why? Because, girl, you'll be a woman soon. It was as big as four rooms.

Four rooms. Look, I'm not going to do this any more. I was going to fill this post with references to Quentin Tarantino films from the 1990s but I'm not going to do that. Let's move on. Here's what my modular synth looked like, the last time I photographed it:

It's not a true romance, because the bottom half is mostly a Behringer Model D; only the top half is made out of modules. It's built into a Doepfer LC6 case, which is 84hp wide and two layers tall. The whole system is about the size of a slightly smaller-than-usual PC case, but not as heavy.

I've made a lot of music with it, viz:

There's a stereotype that Eurorack is addictive. The individual modules aren't that expensive, but they're desirable and the cost mounts up. £70 here. £120 here. £60 there. You have to give up smoking and drinking in order to afford more modules. Then you start cycling to work instead of driving. You cancel your gym club membership and sell off the Peloton. Before long you're a shell, a shattered ruin.

Would my music benefit from a ribbon controller? An FM radio? A low frequency oscillator that takes two hours to complete a cycle? Probably not, but how will I know unless I try? And by "try" I mean "spend money".

They're so beautiful.

But let's imagine that you're disciplined, and you want to build a little modular synth without spending too much or taking up too much space. Doepfer's smallest case is 32hp wide, which is either a challenge or too limiting depending on your outlook, but the company makes a slightly-less-miniature model, the 48hp Doepfer LC1:

It has twelve power connectors, which is nice but overkill. 48hp is enough for five or six regular-sized modules. A company called 2HP specialises in 2hp-sized modules, so if you buy lots of 2HP modules you might run out of power connectors, but you'd have to try really hard. Perhaps you could fill the empty space with passive low pass gates and attenuators. I'm digressing.

How did I fill my LC1? At first I did this:

Doepfer warns that the LC1's power supply is less stable than the power supplies in larger cases, which can cause analogue oscillators to go out of tune. Digital oscillators shouldn't be affected, so initially I built my system around Mutable Instruments Plaits.

From left to right the case has Plaits, a Doepfer A-101-2 filter, a Doepfer A-118 noise generator, a Doepfer A148 dual sample-and-hold, and a Behringer 140 dual-envelope-plus-LFO. It would be nice to have more LFOs, but I felt that the S&H circuit would compensate for that. The following tune uses this setup:

Ashley Pomeroy · Mini-Modular 1

It also features a Meris Hedra pitch-shifting delay pedal, and Valhalla's Supermassive reverb VST.

The Hedra is great fun. I'll write about it at some point. It has three delay lines, which can either echo the sound as-is, or they can shift the pitch. It works best with monophonic sources, and preferably simple waveforms, and sometimes it goes wrong, but when it works it's like having someone play chords along with your music. About the only technical issue is an odd crackling at very high frequencies, which means that if I feed it into a reverb I have to roll off the top end otherwise the reverb result sounds crunchy. Enough of the Hedra.

How much did this modular marvel cost? Brand-new the LC1 is around £140, Plaits is £195, the A-101-2 £95, the A118 £60, the A148 £60, and the 140 £75, which is a total of £625. Ouch. That's not cheap. And you still need a bunch of cables, and a way to control it all. I used an Arturia Beatstep (£75), which doubles as a MIDI-CV interface, with an odd quirk whereby everything is transposed up two octaves. I also have Mutable Instruments' Yarns, an excellent MIDI-CV interface, but at 12hp it would take up as much space as Plaits.

But! with the exception of the Behringer 140 I slowly accumulated all of these modules on the second-hand market, from eBay, so I paid around £450, which is still not cheap, but there is an even more valueful option. Consider the following:

This is built around a Behringer 112 dual VCO, which is a pair of analogue oscillators. Despite Doepfer's warnings about instability the 112 worked fine and remained stable, although tuning it was difficult because the tuning knobs are very sensitive.

The setup above has the LC1, a multiple (£20), the 101-2 filter, plus the Behringer 112 and 140 modules. The Behringer 112 costs around £80 brand-new, so the whole setup would have been £410, but as mentioned I bought most of it second-hand and thus got it under £400. The end result is sonically in the same ballpark as a Roland SH-101, with a second oscillator instead of a sub-oscillator. It would benefit from a noise source and an attenuator, which I could perhaps have fitted into the case if the envelopes and LFO were smaller.

Here's what it sounds like, fed into Logic, this time with a Strymon El Capistan tape delay pedal:

That tune begins with the two oscillators playing the same notes, an octave apart, and then after a short while I play a different set of notes through the second oscillator. It all goes into the same filter, modulated with the same envelope, so although there are two notes at once the result is paraphonic rather than polyphonic. One thing to note is that the system doesn't have a VCA. I use the filter instead.

Oh yes, this setup has a Doepfer A-103 VCF6, which is modelled on the filter in a Roland TB303. At higher resonance values the A-102 shrieks loudly and outputs a sine wave. The A-103 on the other hand just gets more squelchy.

In this setup I'm using it as an expansion for a Behringer Model D, passing the two extra oscillators through the Model D's filter and envelopes, and passing the output through the LC1's spring reverb.

Could I have pared things down even more? I could have eliminated the S&H module, saving £60 at the cost of some flexibility. Behringer's System 100 range also includes the 110, which sells for £80 and has a single VCO, a VCA, and a VCF. A setup that consisted of a Behringer 110, 112, and 140 would fill the case for £380. Alternatively I could have eliminated the filter and used my TAKAAB 2LPG, but this module doesn't have resonance, so the results wouldn't be squelchy.

Is a 48hp case practical? On the positive side the system above is small enough to fit into a backpack and has roughly the same sonic power and flexibility as a Roland SH-101 or a MiniMoog, at a price of around £400. It's not quite a Korg MS-20 but if the modules were jiggled around it would come close. It would also be a good housing if you have a computer-based, virtual-instrument setup but wanted to try out 2HP's Pluck or Mutable Instruments' Plaits or something analogue.

This minimal setup uses a pair of Volcas and an Arturia Beatstep to generate sync pulses, and Dexed - a VST simulation of a Yamaha DX7 - being played with an Arturia Beatstep. The only two modules that are actually doing anything are the dual logic gates and the 2LPG.

48hp is however very limiting for a complete self-contained instrument. I still had to do a bit of jiggery-pokery with TipTop stackable cables on the dual VCOs because there wasn't room for any multiples. Doepfer's 84hp LC3 case is a much better option for that. 48hp does however make a lot of sense as a break-out box for passive modules, or modules that you rarely use, e.g. the dual logic gates in the video just above.

2706: It was Good to Be Human

Let's fire up my modular synthesiser yet again and make some more music. This piece - 2706, which is also falsely called BREAKS - doesn't have a clever technical trick or anything like that. It's just Mutable Instruments Plaits run through a Strymon El Capistan delay pedal, sequenced with an Arturia Beatstep. I decide to use Plaits' FM mode because why not.

The strings in the background are coming from a Behringer Model D playing the same sequence, with a slow attack. Both sound sources are being modulated with copious LFOs. In retrospect I should have made Plaits slightly quieter towards the end because it starts to distort. The song is a kind of endless grove that could continue indefinitely.

One of my favourite musicians when I was younger was Jean-Michel Jarre. His albums were technically fascinating, not least because they were recorded in Beatles-style stereo, e.g. everything was hard-panned to the left or right. As such you could hear how he achieved certain effects by fiddling with the panning control. He used a lot of stereo delay on his early albums, with the original signal in one side of the stereo field and echoes on the other.

His 1981 live album The Concerts in China in particular has a track called "Arpegiator" that uses a classic idea - the dotted eighth delay. The track is essentially a pair of simple, robotic sequences fed into a delay unit that produces a three-quarter-beat echo. By itself the sequences go dah-dah-dah, which is boring, but with a dotted eighth delay they go dahgha-dahgha-dahgha, which is exciting.

Do you understand? Not dah-dah-dah, but dahgha-dahgha-dahgha. The first song I can think of that uses the effect prominently is Pink Floyd's "One of These Days" from 1974, but I wouldn't be surprised to learn that a bunch of surf rock bands used it in the 1960s. It's all over The Wall, and U2's The Edge made it his own in the 1980s.

Jarre uses the effect on the steady bassline in a style not a million miles removed from Tangerine Dream, and also on the more staccato melody, where the echoes are allowed to die away naturally.  He mostly avoided sequencer effects in favour of old-fashioned tunes, and "Arpegiator" it's atypical of his work, not least because it has a bass solo. For me it was one of the highlights of that album.

Concerts in China is an odd beast. It's a mixture of new songs and old favourites re-arranged for a small albeit well-equipped live band that included a drummer, because Jarre wanted the music to sound a little bit like conventional Western rock and roll. His only major concert before then was a live show in Paris in 1979, where the music was entirely played back from tape, but for China the band did actually perform live.

There are apparently lots of studio overdubs, but the playing matches up with the footage shot for a contemporary television documentary so not all of it was worked on in the studio. It's fascinating because there's a ragged, almost garage-band looseness to the playing that never again appeared in Jean-Michel Jarre's work. His later concerts again mostly involved miming the playback, because everything had to be synchronised to huge projections, but just this once his live sound was actually live, just like The Ramones, but with a hugely expensive Fairlight sampling workstation and a laser harp.

Endlessly Variable Plucking

Let's fire up the modular synthesiser again, and chase away a rainy day.

The track at the top of this article was performed with the Odyssey pictured above (it played the strings in the background) and Mutable Instruments' Plaits, which is in the middle of the top row of the modular case. Plaits has a clever guitar-string simulator that resembles 2HP's Pluck, but with more modulation options.

Not pictured is a Mac Mini, a bunch of effects, a MOTU 828 audio interface, and an old copy of Logic Express 9. And a pair of Arturia Beatsteps, which I used to sequence the notes. The Beatstep is a simple 16-step pattern sequencer that has a mixture of CV/Gate and MIDI outputs:

I could have plugged them directly into my synthesiser, but instead I fed them both into a Doepfer A-166 Logic Module:

How does a logic module work? Have a look at this fancy table:

That's what the internet looked like when I was young. It's what computer games looked like when I was young. But, still. Logic gates.

If two triggers coincide the logic module spits out a trigger from the AND output. Alternatively if there are triggers in pattern one or pattern two, the logic module spits out a trigger from the OR output.

It dawns on me that the A-166 doesn't have a NOT gate. It has a XOR gate instead, which is an acronym for "eXclusive OR". AND and OR and NOT aren't acronyms, by the way. They're words. I wrote them in capitals to emphasise them. Not because they're acronyms.

XOR gates differ from OR gates in that they only generate a pulse if either one or the other input is active, but not both. In the diagram above it would generate a pulse at step 2, for example, but not steps 1 or 4.

Why bother with a logic gate? If the result of combining pattern one with pattern two is pattern three, why not just play pattern three in the first place? Logic gates are useful for modulating a sequence with a second sequence. In the case of the song at the top of the page the note pitches are generated with one Beatstep, but the notes are triggered by a separate, random pattern from the second Beatstep, fed through the logic gate. The result is a guitar melody that runs through the same set of notes, but with endlessly variable plucking. And because the two sequences were running out of sync, there are occasional note bends where the steps didn't align.

The second element of the track is a typical space reverb pad, which I generated by feeding my Odyssey through a mixture of a Strymon El Capistan delay pedal and a big reverb plug-in. This tune has a similar idea, but with a chunky bassline:

Will the weather improve? No, according to the weather report it will not.