Mom, can we buy Strega? No, we have Strega at home.
Strega at home:

Two years ago, when Strega had just come out and that first wave of influencer videos was inescapable, I made several attempts to build my own version of it with the pieces I had. And you know, it kind of worked back then! I got some Strega-like sounds out of my attempts. You can hear for yourself here:

https://metapop.com/ether-diver/tracks/if-you-would-hunt-witches-you-must-hunt-them-in-the-sky/174255

Well well, wasn’t that bracing! Anyway, since I now had a Strega in my possession I thought another attempt might be worthwhile. And here it is, my attempt at Strega, with about 50% of the functionality, 30% of the sound, and 300% as confusing!

Sounds like Strega! Sorta?

Obviously, this patch is mostly interesting for educational purposes, and maybe to offer just a touch of insight into how well Strega is actually engineered, designed and tuned to be what it is. After all, I find one of the most useful ways to learn about how something works is taking it apart, and while I have no desire to dismantle my $500 synthesizer, I am more than willing to “take it apart” metaphorically by recreating it!

We start with a Klavis Twin Wave output giving us a triangle wave. That goes into the Klavis Flexshaper, the output of which is multed into the Koma Field Kit FX ‘s pt2399 delay and its mixer; a second mult sends the output directly to a crossfader.

The Field Kit FX delay output is mixed with the dry (but waveshaped!) output in its mixer (minimal tone shaping can be applied here as well with the mixer tone controls) and the wet/dry mix is sent to the Doepfer SEM filter ( my mellowest filter, and the Strega filter seems relatively mellow, but this could have been any other filter and they might have been closer). The filter output goes to that aforementioned crossfader, which is the Disting mk4 in one of its many guises (Algo H1. for reference). The output of the mix goes to a Tallin VCA then to the mixer.

That’s it for the audio path, and it’s relatively straightforward. The control stuff is where it gets complicated…

I don’t want to get deep in the weeds here, so I will try to keep it brief. If I go too brief, shoot me a comment or social media message and I’ll add some detail or answer any questions you have.

Let me start by admitting I didn’t even try to do anything like a complete 1-to-1 recreation of all the controls! I don’t have touchplates! I didn’t mess with an envelope follower (or any external in for that matter). I didn’t even bother to plug up the Agitation generator, because it’s a straightforward function generator and I understand those very well (the function generator on the Pittsburgh Lifeforms Mod Tools is very close to it, so let’s pretend I used that for the sake of completeness).

What did I include? Well, the subharmonics seem to get sent everywhere, so I decided to patch those up. I used the sub osc output of the Twin Waves, which gave me a square wave one octave below my fundamental. That went to the Make Noise Function’s input, and I used the rise/fall controls to slew the signal, giving me a subharmonic at the output. And it worked! I think! (Someone smarter than me feel free to explain why No, Actually, It Did NOT.) In any case, the output I got seemed more or less what I was expecting. (And then I didn’t even end up using it except for the EOC trigger, which is used in the next bit.)

Similarly to the subharmonics, the filter + delay derived CV output seemed important, so I made one. I used that aforementioned trigger to trigger the sample and hold circuit in Kinks. Instead of the noise source internal to Kinks, I used the bandpass output of the SEM filter the delayed signal was going through. And again, it definitely gave me something close to what I was expecting based on the Strega — a chaotic, seemingly random CV signal that sputtered and spit and got weird. Cool. That got fed into the FM input of my oscillator, and I also wired up a mult on this with a cable I can plug into the VCA, as on the Strega, complete with attenuation (via the Doepfer A-135-2 VCA, acting here as a simple attentuator).

To control the waveshaper (because the Flexshaper is an odd duck and I am too) I set up a symmetric +/- voltage control via the After Later Blend module — outputting its offset voltage from channel 1 to the input of channel 2, and inverting it, then multing both outputs, attenuating half the mult, and applying the unattenuated and attenuated versions, respectively, to the top/mid high and bottom/mid low controls — basically, as you turn the knob, the wave gets increasingly bent out of shape. Probably more effort than it was worth, but it was a fun exercise!

That’s where I quit, to be completely honest. The more I added, the more I realized I needed to add — it was at the point I realized I should incorporate the matrix mixer that I decided, “Hey, you know what? We got close enough.” This Strega has a lot going on under the hood!

So I basically learned two things. One is that, yes, if you squint and don’t compare them too closely and completely ignore the elegant and natural feeling control built into the actual Strega, you can patch up a reasonable version of your own with relatively common modules. The pt2399 delay is probably the rarest, and there are still plenty of modules with those out there! (In a pinch, use your shittiest, most lofi delay — the harder to control, the better.) Wavefolder, filter, some mixer, some mults — it’s not that hard! But it’s not that easy, either, is it?

There does indeed seem to be some real magic behind the panel of Strega. The components are all tuned well to work together, and it all feels good! Not so on my little cobbled together version. The tuning of my pt2399 delay is way off from the Strega, for one thing, so it controls a lot differently — they have similar ranges, but they don’t overlap completely. Of course that’s merely one of dozens of things, but the point is, the Strega really is more than sum of its parts. Rest assured, I’ll be delving ever deeper into it soon…

Until then, here’s a quick video version of what you read!


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