I have big plans for 2022: I’ve already tentatively scheduled nine performances at various events, plus I would like to release some new albums. This has meant updating and overhauling my studio, tweaking the Monster (the studio modular) and replacing the Tardis (my travel modular).

Which has brought me face to face with mundane tasks such as getting all of my oscillators and other sound sources to track each other. This is an exercise I have been through many times, and I get better at it each time I do it; my latest advice is in the featured article below.

I also have other updates to report, as well as a question to ask: Does the world need another synthesizer podcast?

• featured article: New modules seem to rarely track the others already in your case. Here is how to calibrate them to what is required by your particular system.
• Alias Zone updates: How to be first to hear new Alias Zone material.
• Learning Modular updates: My Learning Modular Conversations with Kim Bjørn of Bjooks (Patch & Tweak, etc.) is now public.
• Patreon updates: Several posts on module changes to my “Monster” studio system, a linked index to my Ask Me Anything with DJ CherishTheLuv, and musings on Vector Synthesis plus having enough power.
• upcoming events: Lots of things in the air…including Covid, which could change it all.
• one more thing: Does the world need another synth podcast? By me?

The Right Way to Calibrate Your Oscillators

One of the most frustrating things about working with modulars is that when you get a new oscillator or other sound source, it often will not track pitch control voltages the same as your other oscillators, going out of tune as you play different notes. This is usually because each manufacturer has their own calibration procedure when they made the module, and their system is almost guaranteed not to match the realities of your own modular.

Fortunately, most oscillators have “trimmers” that allow you to tweak the way they respond to incoming pitch control voltages. And for those that don’t, there are modules that can externally calibrate your sound sources.

I have an ever-changing collection of over 20 oscillators and other sound sources, so this is a battle I’ve been fighting for a few years now. Based on personal experience, here’s my advice on how to deal with various tracking problems.

The Little White Lie that is The Truth

To calibrate your oscillators correctly in the real world, you may need to ignore part of the instructions that come with the module.

Most calibration instructions say something like “send the module exactly 1.0 volts, then exactly 3.0 volts.” The truth is, what you’re using to control the pitch in your own system probably does not output exactly 1.0 or 3.0 or any other precise value like that; they are usually off by a few fractions of a volt (millivolts). The more modules you send your pitch control voltage through – such as buffered multiples and quantizers – the more like that control voltage is to be slightly off. It’s a reality caused by the variations between different individual components in a circuit, and would take a lot of extra parts and time for the manufacturer to perfectly trim for each individual module.

If you calibrate your oscillators using a perfect reference, then send that same module the imperfect control voltages that exist in your own system, of course the tracking will be off! So here’s what to do instead:

The Procedure for Calibrating Oscillators

Turn on your system and let it warm up for at least a half an hour, so the temperatures inside your case can stabilize – this will affect how a lot of modules process the incoming control voltage.

While it is warming up, patch the output of your controller through the entire module chain you would normally use in front of your oscillators. You might be patching your controller directly into your oscillators; you may be going through a buffered multiple first – or you may be sending that control voltage through several modules before it finally reaches the oscillator. To give an example, in the picture at the top of this article the Pitch output of a Five12 Vector sequencer is going through:

• an Intellijel buffered multiple
• then an ALM Beast’s Chalkboard, so I can manually offset the CV by octaves
• then a LPZW WK1, so I can transpose that CV with an external control voltage

…and then it finally reaches the oscillators. Each of those modules above is adding its own slight deviation to the desired perfect target voltage – but that imperfect result, regardless of your own signal chain, represents what is really going on inside your system.

Pick a module you want to calibrate, and see if its manual has any specific instructions. Mutable Instruments modules, for example, ask that you to send them 1v, and then 3v, during their calibration procedure. When there are no explicit instructions, lately I’ve been using 1v and 4v as my references.

In most systems, the note “C” is supposed to be some multiple of 1.0 volts. For example, the Vector sequencer has a -3v to +7v range for pitch CV, with C0 = -3v, C1 = -2v, C2 = -1v, C3 = 0v, C4 = +1v, and so on. Using a multimeter connected to one end of a cable patched into the last module in your pitch CV chain, figure out which notes on your sequencer (or controller keyboard, or whatever you’re using) is the closest to what your module’s manual suggests. In the case of Mutable’s request for 1v and 3v, that works out to C4 and C6 on the Vector.

Then follow the instructions that came with your module to tune the oscillator. If you didn’t get explicit instructions, play a C on your controller that has the output voltage nearest to 1.0v, and tune the front panel pitch controls on your oscillator to output a C as measured by a tuner. (If you don’t have a tuner, tune another oscillator with no control voltage coming into it to what you consider to be C, and then mix it with the output of the module you’re calibrating. Tune the module you’re calibrating until you don’t hear any “beating” or detune between the two oscillators.) Then play the C three octaves above it, and tweak the internal tracking of your oscillator to match that higher C.

Repeat as needed, between the front panel for the low voltage and the trimmer for the high voltage – oscillators often require you to go back and forth between the low and high notes several times to zero in on the exact target calibration. Now it will be calibrated to properly track the realities of your own modular system, rather than some ideal set at the factory or imagined inside the manual.

No Trim Controls? Then Use an AJH V-Scale

Some modules – including many filters, and some digital oscillators – may not have trim controls. Others require you to remove the module from the case to get at those trimmers – which changes the temperature around the module, which in turn can change its tracking compared to when it is inside the warm confines of your case. A few modules may use cheap trimmers that make it hard to hit the exact target.

If you have one of those problems, and the module is not tracking correctly inside your system, I highly recommend getting at least one AJH Synth V-Scale Variable Precision Buffer. This gives you a set of high-precision, front-panel trimmers where you can really tweak the tracking of an oscillator patched into it. Use the same procedure as above, but this time do the trimming on the V-Scale module. Click here for an article and pair of videos that demonstrate using the V-Scale to improve the tracking of an oscillator and a filter.

Need Quick Tuning Offsets? Or Have Other Problems? Then use a Klavis CalTrans

I like to play with tuning multiple oscillators to different semitone or octave offsets – sometimes in the middle of a performance! Unfortunately, very few oscillators have octave offset controls built in – or, they put the oscillator out of tune when you use them.

Also, there are some oscillators that don’t track in a “linear” fashion: going from C to a C an octave or two higher may track well, but a note in between those two might be out of tune.

In both of those cases, I use a Klavis CalTrans to add semitone and octave offset controls, and if needed to create a custom tracking calibration table for an oscillator. (The CalTrans also has other features, such as adding glide and quantization if desired.)

I usually start by following the CalTrans’ procedure to create a “neutral” calibration, and see if the oscillator tracks nicely using that (also calibrating the oscillator itself – or by using a V-Scale – if needed). You also have no choice but to use the neutral calibration with “pluck” style oscillators such as the Mutable Instruments Rings, as they do not produce a steady, simple waveform for CalTrans to read during its auto-calibration procedure.

If I have problems with the tracking wandering from note to note with a normal (constant-tone) oscillator, then I use the normal CalTrans calibration procedure to create a custom calibration for a specific oscillator. Simple waveforms like a sine wave work best; if I am having trouble getting a good calibration, I will try different waveforms such as a square wave. Make sure you are reading the most recent version of the manual, as it has updated advice on how to set up your oscillator before calibration.

The secret trick to using a CalTrans successfully is to accept that it has issues tracking CVs around 0 volts. This problem is not specific to the CalTrans; a lot of digital oscillators also only recognize pitch CVs from 0 volts on up, plus they don’t respond correctly to a pitch of 0v. (It’s an issue with the calibration of some analog to digital converters, if you’re curious – some circuits are bad at detecting 0 volts.) I’ve even encountered an analog oscillator that tracked differently below 0v than it did above 0v!

To work around this, after calibration, figure out which “C” on your controller outputs 0v – C3, in the case of the Vector Sequencer – and always select notes above this value. Choose a note that is a little above that 0 volt C, and then tune the oscillator at its front panel to produce the lowest corresponding pitch you ever intend to use. For example, E0 has a pitch of 20.60 Hz, which is at the very bottom of audibility. If you then need to transpose the pitch CV after your sequencer or controller, use the controls on the front panel of the CalTrans. Just stay away from going down to 0v or below on the controller (and to be safe, I also try to avoid transposing the CalTrans to where it outputs below 0v – which you shouldn’t need to do, as you already tuned your oscillator to the lowest usable pitch when just above 0v).

That may seem like a lot of information to keep in your head…but when I work this way, I get oscillators that track within a few cents of each other over several octaves, instead of going sharp or flat in as little as one octave. Then I can get on with making music. I hope this saves you some time and frustration as well.

Alias Zone Updates

After a slow second half of 2021 (due to recovering from my broken leg, a studio re-wire, and reconfiguring my live system), I am planning to create and share a lot more music in 2022. As I book new performances and release new albums:

• performance dates will be posted first on the Alias Zone web site (as well as the Alias Zone Facebook and Instagram pages)
• new videos will appear first on the Alias Zone YouTube page
• new albums will appear for download on the Alias Zone Bandcamp page

If you could follow or subscribe any or all of the above, I would really appreciate it. The links above to YouTube and Bandcamp in particular will make it easy to do. I promise not to spam you (smile).

Learning Modular Updates

My third “Ask Me Anything” session for my Learning Modular Patreon subscribers has been made public on the Learning Modular YouTube channel, under the playlist Learning Modular Conversations. This one was with Kim Bjørn, the founder of Bjooks, and who I helped write Patch & Tweak. Kim and I are good friends, and he came prepared with a great list of questions – many of which I made sure he answered as well! If you click the Show More link underneath the video, it will reveal an index of all of the topics we discussed, including links to take you directly  to that section of the movie.

Patreon Updates

In December, I had a wonderful “Ask Me Anything” session with DJ CherishTheLuv. Since the last four sessions had focused on guest hosts asking me questions, we turned the format around and talked more about Cherish’s personal journey (including overcoming a head injury, cancer, and more), with me chiming in with my own experiences where appropriate. We talked a lot about personalizing your performances, and Cherish actually played a short piece live for as well as demonstrated her use of biofeedback with modulars. The playback with linked index can be found here, and is available to all subscriber levels.

I also continued my series documenting changes to my Monster studio modular system since it was introduced in the Feeding the Monster series with DivKid, including explaining each of my module choices. The two areas covered last month were filters, and submixers, VCAs, and LPGs. Those two posts are available to +5v and above subscribers.

I also wrote two standalone pieces: one on why the Prophet VS sounds different than most other morphing or crossfading wavetable oscillators (with demo and patch ideas), and one on my latest experiences with specifying how much power you actually need for your modular system (including how overloading your power system can introduce noise). Those two posts are available to all subscribers.

Upcoming Events

I’m almost reluctant to list my upcoming performances, because I’m afraid I might jinx them with the Omicron variation of Covid floating around. Plus, details are still being finalized. But let’s take a chance and share at least what I know so far about my next two gigs:

January 22: SCSS streaming on YouTube

For a long time, I had been planning to be part of the 2022 edition of the “NAMM Jam” put on by the Southern California Synth Society (SCSS for short). When I broke my leg July of last year, I was told the soonest I could expect to heal was in six months – which made January NAMM a goal for my recovery. Then NAMM was cancelled and moved back to June 2022. However, the SCSS is still planning on doing something, and I’m still planning to be part of it. Mark January 22 on your calendar, keep an eye for announcements through both their and my social media outlets, and bookmark the SCSS YouTube channel as that’s where they’ll be streaming the event.

February 11/12: Phoenix Synthesizer Festival

Again, plans are still very tentative, but I’m hoping to give a presentation on my new performance system – as well as a live performance using it – as part of the next Phoenix Synthesizer Festival. We’re hoping some form of live audience will be allowed; streaming of the event is also planned. Keep an eye on their website for news, and in the meantime watch both Day One and Day Two of last year’s amazing event which included educational presentations as part of each performance.

One More Thing…

When I broke my leg, I was trying to figure out a way to keep creating useful content for my Patreon subscribers. I came up with the idea of doing a series of “Ask Me Anything” Zoom sessions, so they could ask me what was on their minds while I was unable to create new videos and posts of my own. I then decided to invite a different co-host each month to also ask me questions, and so that my subscribers would have a different person to talk to each month in addition to me.

Instead of a grab-bag of random questions, what happened instead was a series of deep conversations about electronic music composition, recording, and performance. They were so good, that I decided these conversations should be shared with a wider audience. Click here for a playlist of the first three sessions, which I’ve renamed “Learning Modular Conversations.”

The next two sessions after these took different turns, with me breaking down some of my tracks and patching tricks in the fourth episode, and what turned out to be me interviewing DJ CherishTheLuv (instead of the other way around) in the fifth episode. These will be released publicly in the next two months. (But since you’re making the effort to read this, you can click on the links above to get early access to those playbacks.)

Out of this came the question: Should I make this a regular series?

• On the one hand, a large number of streaming “synth shows” have appeared over the last two years in particular – so many that I know I can’t keep up myself! So it seems crazy for me to try to start yet another show.
• On the other hand, I do think we have gone deeper into more complex, “evergreen” subjects such as composition and performance, compared to the usual (but still useful!) talk about the latest modules and the such.

What’s your opinion? Be honest – would you be interested in a regular show like this? Would you have time to watch it? Should I instead put my energy into appearing on existing shows, such as the Synth Show episode where I was the guest, and which still got into a lot deeper material? This is not just about me trying to generate publicity (or ad revenue; I don’t allow ads on the Learning Modular YouTube channel); it’s about whether or not you would find it genuinely useful, as it will take a bit of work to pull together in a way I would be proud of.

Let me know in the comments below.

Thank you for your support through the years, and particularly through a challenging 2021: I really appreciate it, as it enables me to spend my time learning these wonderful instruments – and sharing the results with you. Here’s to a fantastic 2022 for all of us.

warmest regards –
Chris