Thursday 29 July 2021

Rebel Technology's Witch

I'm going to start by talking about an older product, but so that I get a picture of the new product on the Interweb, then I have to include it here, first. So here is: The Rebel Technology Witch:

The Rebel Technology Witch

I've mentioned Rebel Technology before... I like their open hardware, open source, 'open' approach to making synthesis and audio processing devices, and so I bought an OWL effects pedal from them, added a footswitch (one of the advantages of making technology open is that you can easily get the circuit diagrams, and other technical design details!), wrote some Gen patches for it, and generally loved it. OWL1  OWL2 I still do!

Rebel Technology's OWL Pedal

(In a world where guitar pedals continually try to out-do each other with eye-catching designs, the OWL still managed to be spectacularly bold! IMHO)  

So, here we are, a few years later, and Rebel Technology asked me to help them with beta testing of a forthcoming new device! I was overjoyed, of course, because it was like several generic mid-December festivals/holidays all at once! In those years, of course, things have changed a lot, except, in this case, the size of the device, and the Gen programmability (plus lots of other programming languages!). So, here's the device for which I have been one of the beta testers... The Rebel Technology Witch... (and that picture again!)

Rebel Technology's Witch

As you can see, the influences for the Witch are very different to the OWL. There are bits of Eurorack (the 3.5mm patching jacks), bits of desktop synths (the knobs and the four buttons), and modern MIDI design (USB host socket, USB socket for WebMIDI).

What you can't see are polyphony, versatility, MPE, a Class Compliant Audio Interface and lots more. Although some of the OWL patches will run on a Witch, there's more processing power and broader capabilities in the Witch. There's also lots more detail about the Witch on the Rebel Technology web-page:  Pre-built and kits...


In a world where programmability is rapidly becoming the norm, how do you design something new and different? The Witch is a perfect example of one way to go in a very different direction, by combining programmability with patching, and mixing up bits of modular synth flexibility with desktop accessibility. The first break from tradition is those patch sockets. You are probably expecting them to be for just hooking the Witch to a Eurorack modular system, and you would be half correct. But those sockets are also outputs for the internal LFOs (or envelope followers, or whatever else you program them to do), and those sockets next to the buttons control the buttons - with the buttons controlling functions inside the software running on the Witch. So a button might trigger a note, or sustain a note, or change the audio routing so that the sound goes through a filter, or through an audio effect, or change the algorithm used for an audio processing algorithm, or tap-tempo for an LFO, or a gate, or... (whatever can be programmed...)

And whatever the button does, you can activate it using the associated socket. The four main rotary controls also have jack sockets inputs as well, and so you can control them via patching as well. Actually, you can use them as Offsets, or as CV Attenuators, because there's a tiny black 'Mode' button right in the centre that provides extra control over what does what. 

So you can patch the Witch itself, using its own sockets - an LFO might be connected to control the time of a delay, or the frequency of an oscillator, or the cutoff frequency or a filter. Or an envelope might be used to control the delay time of an echo, or anything else. But here's the really interesting bit - the CV output and gate sockets are programmable as well, so whilst the factory synthesis patches have LFOs assigned to those four red sockets, there's nothing that stops a programmer assigning them to other purposes. One of my (coming soon) patches outputs an envelope follower, for example. So this isn't patching replacing a modulation matrix, it is open and reconfigurable modulation sources (and destinations) as well. Another of my 'coming soon' patches outputs LFOs that run at different rates to the ones that are used inside the patch running inside the Witch. I'll say that again in marketing speak: if you've wanted to have a different LFO rate for the filter mod, the phaser and the stereo panning, then the Witch can provide those LFOs, and if you derive them from the same master LFO, they will track each other... You just need to hook the Witch to a phaser and a stereo panning module...

A quick reminder before you get too focussed on hooking it up to modular again -  the Witch isn't just something that you can connect up to a modular Eurorack system (or, actually any synth!), it is, itself, a tiny reprogrammable, modular synth that you can patch to control itself. This kind of goes against one of the paradigms that you often see in many modular synth modules - they are designed to be patched to other modules, and it is quite rare for a module to patch itself. And that patching is between sources and destinations that are also programmable! (Your jaw is allowed to be slack here...)

At this point, you might, like I did, be thinking about two Witches...(or more).  A coven of Witches would allow you to program just about any functions you want (or can find a patch for, or can write, or can persuade someone to write for you) into the Witches, and then to patch them: locally on one Witch, or across/between the Witches. There's really only one word to describe the possibilities that this opens up:


Having something this flexible, versatile, patchable and totally programmable in a form factor this size is very probably a game changer for anyone who wants to explore modular synthesis (or add a little bit of extra synthesis power to an existing keyboard or desktop synth), but doesn't want to be tied to using a large monster of a rack. Actually, it is an interesting add-on for someone who has an array of keyboards, because that USB socket provides access to USB-MIDI, and so the Witch is an expander as well - except that this is an expander that kind of also eases you into modular. Desktop synths are another potential companion for the Witch, so just about anything synthy that has MIDI, USB  or CV sockets is potentially suitable - so a Novation Circuit (OG or new), there's a YouTube video of a Witch and an Ensoniq SD-1, or a Deluge, or... One way of looking at it is to consider the programmable modules that you can already get for modular synths, but turned into a stand-alone little box - that's what the Witch is. And if you like the sound of a totally programmable module, then Rebel Technology made one of these programmable modules in collaboration with Befaco - it is called the Lich:  
So whilst most people think of a programmable module as a way of getting a custom module that does exactly what they want in their modular system, a Witch is not constrained to working as part of a modular system. it can be stand-alone, or work with other Witches, or work with a modular system. A Witch provides freedom to do whatever you want - want a wavetable synth (or a Speech Synthesis algorithm like Vosim, or...) to go with a Virtual Analogue synth: Done!. What did I do? I programmed a drone generator into a Witch and realised that it would be just a small part of my personal cabin baggage allowance for a flight... (whenever that mode of transport returns to whatever new normal eventually arrives...)

Someone, nay, several someones, is/are going to do something very interesting with Witches - of this I am pretty certain. It might not be immediately obvious (like Depeche Mode (and others) hiding their synths in those big black wedges on stage for some tours (which ages me a bit!)), but it seems like a very real possibility. 

The Problem

When you have something that can be a VCO, a VCF, a complete wavetable synth, a VOSIM voice synthesis system, a sample replay box, a flanger/resonator, a couple of complex LFOs, and much more, then it gets difficult to make decisions. They say that the biggest spur to creativity is limitation, and whilst the Witch has limitations, it also has lots of flexibility. Possibly the most interesting thing about the 'Someone' that I mentioned is who they are - I'm expecting someone with aspirations and limitations, who has never had or used a large modular. These are interesting times. The mix of hardware and software seems to be reaching a critical mass, and that usually results in an explosion!


Yes, I am, indeed, biased. Having done some of the beta testing of Witch then I am way too close to be independent. This is why I'm not doing a full review of the Witch. For that I would point you towards Loopop, or Benn Jordan, or Andrew Huang, or CDM, or your favourite source of insightful comment and review. 

But, I still know something interesting, different, and exciting when I see it! Full marks to Rebel Technology for stepping well off the 'path well trodden'. 

In an astonishing break from normality, I have made some videos! They are, of course, slightly quirky, but you expected that, didn't you? Here you go:

#rebeltechwitch.     - Hashtag for the Witch  An unboxing video!  A very quick intro...  Another viral video?


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Saturday 17 July 2021

A Doubly Virtual Talk...

I recently gave a talk to my local tech network. You.know, those things that used to be get-togethers and networking events for tech people, entrepreneurs, start-up people, innovators, inventors, etc., and that people discovered you could do using Zoom during the pandemic. And they obviously work, because we are still doing them.

Anyways, a casual comment I made at one of these tech chats turned into a talk about one of the things that I do, inspired by by soundtrack entry in the famous Westworld competition organised by Spitfire Audio a couple of years ago. It seems that there's a lot of interest in how current technology can make working with audio and music a lot easier than it was in the previous century, and so I just basically did a bit of show and tell...

Remember 'big presentations? Photo by Sigmund on Unsplash

Now when I say 'show and tell', I do mean exactly that. I never wanted to do yet another boring slide presentation full of slides with bullet points. But just watching someone share their screen for an hour is also not so great - I've been in quite a few zoom calls where person after person shared their screen and worked on software, and after watching someone else tweaking MaxForLive for a while, you kind of want to do some programming yourself. Probably my least favourite calls have been the ones where a series of musicians talk for about 30 seconds on some of their techniques, and then spend 20 minutes doing DAWless improvisation. It's the inevitability of it - you get 30 seconds of interesting information, and just when you start to learn about a technique that might be useful, they say: '...and here's a track I put together using a different approach...'. Cue 20 minutes of doodling...

So, no slides, no bullet points, and not too much boring screen sharing. It's a challenging recipe. So I used online videos (mostly YouTube, although I subscribe to Nebula and love it, but YouTube has the advantage of being accessible (and I'm struggling to think of any other advantage...)), web-pages instead of photos 'from the internet', and yes, some screen sharing where I avoided any code and concentrated on showing interactive arranging stuff. 

At the end of it, I thought that I should capture it, so that others could have a similar experience, and so the rest of this blog is just the resources that I used, minus the potentially boring screen sharing where I probably droned on about doing music for pictures. So you get just the good stuff to browse through as you wish, and that's all upside, as far as I can tell... 

(When I type: 'Just the good stuff', there's a caveat, but you probably know that already - you have to wade through me adding all of these explanatory words. Unless you just ignore my words and click on the videos, of course...)

"And now, over to Martin..." <screen goes black>


To set the scene, I used an opening music clip - 'Journey across the Red Planet', an excellent piece of music from Paul Thomson, which demonstrates some of the sounds from the Spitfire Audio 'Abbey One library. (Paul is one of the two founders of Spitfire Audio, a cutting-edge UK ‘sample library’ company: ) I explained that 'everything you are hearing is produced by a computer, using recordings of real instruments'.

I suggested that they should close their eyes for a minute or so, listen(!), then open them and look for the connections between what was happening on the screen and what they could hear. The video shows a DAW (Logic) playing the music, and so you can get some sense of how a DAW uses lots of individual tracks of virtual instruments to reproduce music, and there were piano rolls and MIDI Controller editing shots that illustrate that there's a lot of fine detailed control. Overall, the linkage between the music and the video is pretty effectively shown, but then Spitfire Audio do make vey good videos. So, yes, I started with virtually an advert for Spitfire Audio, but then I do have quite a few of their libraries, LABS instruments and a lot of the associated instruments, so I'm slightly biased. If you've read this blog for any time, then you will have seen that I've been to various events at their HQ (back before Pan Demic and her band put the world on pause for a while...) and I've met Christian Henson and Paul Thomson... (But do they remember me?)

Anyways, the music and the video serve as that all-important bridge, where you leave the real world, and enter the artificial world of 'the talk'. I've never liked the idea that putting up a slide that shows the title of your talk, followed by another slide that tells your life achievements in bullet points, is the perfect way to move people out of their default mind-set and into one where they are ready for fully engaging in a presentation. Closing your eyes and listening helps too, and it often puts any older members of the audience to sleep, so they can't ask tricky questions about DIN sync in the 1970s.

Anyways, I introduced virtual instruments, and how they replayed recordings of real instruments. Or unreal instruments, and so I showed them my BankOSC MaxForLive device that makes 32-oscillator drones and sweep sounds, and basically makes it sound like you have a humungous hardware modular synth, when actually you must have Ableton Live and a free bit of software that I published on

I explained that quite a lot of the non-orchestral sounds that I used in my Westworld competition entry were produced using BankOSC, and I then talked very briefly about MaxForLive, and then Ableton Live.

I've already mentioned adverts, so you won't be surprised that I told them they could read more about the sound generator in my blog:


I found some good links that explain MaxForLive and Ableton Live, curiously made by Ableton themselves:


Ableton Live 

I explained that there are many types of software applications for working with audio, but the terminology that they will probably often hear in music technology circles is ‘DAW’ which stands for Digital Audio Workstation. I said that a DAW is a general purpose music composition and arranging tool that works a bit like a multi-track tape recorder – which is what used to be used in recording studios in the 80s…  I'm quite sure that some of the audience had no idea what a multi-track tape recorder was, whilst some others were probably reminiscing about the 80s and remembering 'Duran Duran' music videos...

For comparison with how you might generate that sort of 'big oscillator' sound in hardware, I should have introduced one of the leading lights of the YouTube ‘Synthesizer’ community, giving an introduction to the vast world of hardware modular synthesis:

But I have the advantage of being able to incorporate it seamlessly here, and no-one will know the difference.

I quickly introduced more relevant terminology in a bot more depth:

Sample Libraries 

(Collections of pre-recorded sounds, where each note that a musical instrument can produce has been captured by a computer, whilst playing it in various ways: soft to loud, different intonations and playing techniques, etc.)

Virtual Instrument 

(The software that plays the sounds of a musical instrument in a sound library.)

And finally, I got to the Westworld competition – where the task was to score a short excerpt from Season 3 of the TV series.

I mentioned my entry:

And I mentioned the winner:

I then revealed that if they were intrigued by just how accessible making music on a computer can be, then a good starting point is an orchestral library (Because the results are probably going to impress parents, friends, colleagues, maybe even ordinary people!) – and some of them are free:

Okay, so I mentioned another free (or low cost) Spitfire Audio product. But I bought Discover, and I like it. There are other free (and non-free) orchestral libraries, of course. 

I closed by reminding them that, whilst laptops (and other computers) may be busy making a lot of music, orchestras are also very occupied doing live tours (often of music produced by computers), making sample libraries - and just making music. And let's hope that as the world learns to live with Covid, 'music' and 'live' and 'performance' can happen in the same sentence once again. 

And that's it. A virtual presentation, made from other virtual presentations. This may be the future...


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