coming back

I have been poking at Akemie’s Castle a bit, patching it up and mostly just chilling and enjoying the sounds, but I don’t feel like I have a lot to write about.

As far as I’m concerned there are no “tricks” to using Akemie’s Castle, except:

  • to me, it sounds best when osc A and osc B are working together as mid/side channels, for big thick unison, chords or clusters. (But it’s not bad to pretend it’s two separate VCOs, either — nor to compromise in the middle with different rhythmic pulses, call/response, etc.)
  • Izotope RX Declick works wonders on the inevitably steppy transitions in operator level when you modulate them.
  • Modulate a lot of stuff. LFOs, envelopes, sequences, whatever. It sounds best in motion IMHO.

I was patching it last night and found I had to go ahead and record it to layer in with something else later. Which I guess breaks me out of the “study” thing and puts me back into music-making mode.

And I think I need it. I’ve noticed some depression creeping in — not super crushing stuff but I’ve been feeling unmotivated and generally down. Feeling a bit overwhelmed by stuff but plodding through it. Wanting to eat more, not from actual hunger. Being disappointed that caffeine and energy drinks and lots of hydration aren’t perking me up more. Wanting to try new, or re-enjoy old video games and not quite finding what I want from it. Not sleeping all that well, and wanting to blame the cat’s antics but knowing I could sleep through / not be bothered by some of his usual bullshit if it weren’t some other factor. Weird-ass dreams, maybe related? It’s all quite possibly seasonal, with longer days and more sun and sometimes warmer weather (temperature has been all over the place). But I know music can bring me to a happier place.

This morning I’ve already listened to two Cocteau Twins albums and have started in on my own Float. I may have to put Vivaldi’s Four Seasons concerto in the rotation too. It’s time for comforting the disturbed, not disturbing the comfortable. I expect that’s the direction I will be taking my next album.

Maybe I’ll sneak some mini-studies in there as I go? We’ll see. My thoughts about gear right now are that I have a lot of it, it’s awesome and a little overwhelming. I could very easily make an album with just Shapeshifter and a few support modules and FX, likewise with Castle, or Kult, or Aalto, or the BrutePest setup. But I feel oddly like that would be betraying my other gear, which probably isn’t a great way to think of things.

I no longer care about Serge GTO or Klavis Grainity or Rossum Morpheus, or any oscillators that I don’t already have. But Blukac Endless Processor is intriguing again. Too bad the “modules in reserve” thing I tried before didn’t work well for me. I still do have some space to spare in the Pod 60 if I can work out some kind of arrangement that makes sense. The cycle never ends…

twists and turns

After Synchrodyne and Shapeshifter, I had planned to dig into Akemie’s Castle next. My issue with it has always been:

  • It’s big. Not too big for what it does, but big enough that I could fit plenty of other options in there. (Or put another way: FOMO.)
  • It’s very much an FM specialist, and I have lots of other hardware and software that can do FM extremely well.

Every time I patch it, I love what I hear, and I keep it around. I even made a whole album to prove it to myself… but it seems I have to keep proving it.

If I just compare 2-op FM on it vs. the FM in other modules or in software, it’s a little quirky but not impressive:

  • Most notably, the amplitude for each operator is quantized to a few levels so modulating it is steppy rather than smoothed — something I can imitate in other modules if I choose to.
  • There’s a certain fizzy/dusty quality to it which is probably mostly due to the resolution of the phase accumulator, but possibly also the sample rate, resolution of the sine lookup table, etc. To a lesser extent that’s also audible in other modules, except Shapeshifter since it’s such a high-specced beast in that department. I can hear it in the SynPrezFM app for Android too, and it’s more obvious at lower pitches.
  • The maximum depth of modulation is pretty darned strong.
  • The frequency ratios are locked to multiples of a common frequency, so you can’t do the slight detuning that I like, nor super-clangorous stuff, or separate sequencing of carrier and modulator. Which is fine, because it allows easy sequencing/modulation of the multiplier, and I have plenty of other opportunities elsewhere for freely tuned ratios.

But Akemie’s Castle has 4 operators, not 2. That’s much less common in Eurorack, though I suppose I could patch it with Just Friends and Shapeshifter in a pinch. It’s considerably easier in software, and I feel like maybe its closest competitor in my setup is Bitwig FM4, or a Grid patch. (Plogue OPS7 is a lovely DX7 emulation, but you can’t just hold a droning note and modulate the operator amplitudes, which is a shame IMHO.) So I guess that’s what I need to compare it to.

[UPDATE]: no, FM4 sounds nothing at all like it.

AC’s operator levels are never exactly 0, and that’s more obvious when using the 4-op serial algorithm. How you set the multipliers and waves matters, and that not-quite-subtle influence coloring the output honestly just adds to the module’s charm.

AC is also duophonic — the A and B outputs can have separate pitches but share a common set of operator controls. B also has a chord mode. There are all kinds of ways to combine the two outputs, especially with the more “parallel” algorithms and different multiplier settings, for really thick chords and clusters, super nice stereo or mid-side sound, or using them with different envelopes/filters/etc.

I’m not sure if I’m going to write up Akemie’s Castle any beyond what’s in this post. Its complexity is more of an intuitive thing than Synchrodyne’s eccentricities or Shapeshifter’s many forms. But I guess I’ll do a quick AC vs. FM4 test, even though I expect I’m going to want to keep AC.

This phase of studying one module at a time in depth is about a month old now, and honestly it feels kind of weird. I’ll think about another module or plugin or the BrutePest setup and catch myself wondering why I haven’t used it recently.

I also feel a little overwhelmed, like I have too much stuff and it’s too powerful and I’m staring into the abyss. I think that’s anxiety talking. To compare synth gear is to compare different infinite sets, and how they overlap both in a general sense and in the specifics of their possible sounds. In the end you just have to pick something that appeals to you and run with it.

And I also wonder how this kind of study is going to apply to actual music-making. I went through the process with Beads, wrote up a bunch of patch ideas and then kept to my old, comfortable, limited habits with it anyway. Going back over those notes and revisiting those patches to see if that shakes something loose is on my list.

Honestly though, what matters is that the gear serves my musical needs, not that I’m taking full advantage of all the possibilities each piece of gear can offer me. Beads’ usefulness to me was never in doubt. Nor was Shapeshifter’s, but I thought its indispensability might be. Synchrodyne’s usefulness was in doubt, but now that I understand its usage and character better, it’s now more a question of will I than can I.

I kind of want to go back to music making again, but I feel there’s plenty more I could learn about my hardware, and also several plugins. I don’t know if I want to plow forward with the studying or return to it at another time.

To be honest I haven’t gotten in a lot of bass practice, either. I kind of feel like, not recording means not feeling the limits of my skill so much, therefore I’m not as motivated to practice. Maybe I need to dedicate some time specifically to bass practice, not try to split it between module studies and bass practice.

My parents got me a Rokr 3D wooden puzzle for Christmas — a steam locomotive model, with a wind-up spring and lots of wooden gears. It’s all laser-cut plywood (plus the metal spring coil and a few rods) and IKEA-like assembly instructions. Everything fits together without glue or additional tools. I finally started working on it over the weekend and am most of the way done. Building it has been enjoyable minus a couple of slightly frustrating moments — the difficulty is rated 5/6 after all. I don’t know what I’m going to do with a somewhat delicate wind-up model train when it’s done, though.

I see they also make marble runs, music boxes, an orrery, clocks, a gramophone, etc. I may have to keep those in mind when considering what I can put on my wish list.

FM vs PM, again

That cool SSI 2130 oscillator chip that many different synth builders have been using lately lists thru-zero linear FM and phase modulation among its features.

Linear FM changes the core frequency up and down equally by some number hertz per volt. So if the modulation signal has a +/-1V range a 200 Hz carrier might swing from 100 to 300 Hz, which averages out to 200. At +/-2V, it will swing from 0 to 400 Hz, which is still in tune, no problem! But at +/-3V, it’ll try to go from -100Hz to 500Hz.

If the carrier oscillator doesn’t support thru-zero, it’s going to have a minimum rate of 0Hz. So the average will be 250Hz, which means it goes sharp. The FM sidebands are “wrong” too.

If it does support thru-zero, “-100 Hz” is just 100 Hz with a reversed phase — so it starts going backwards at 100Hz, and the average frequency works out to 400Hz and it sounds right. The SSI2130 does this using a simple external circuit that feeds a “Time Reverse” input.

But their literature also claims it does phase modulation… and then shows simply using the TZFM with a DC-blocking capacitor (aka a highpass filter) in front. That’s cheating.

*If* you have a sine wave for the modulation signal, and it’s above the cutoff frequency, you’ll get the same results with TZFM and PM. (Except that PM is less strong than TZFM given an equivalent amplitude.)

But there are uses for phase modulation at less than audio rates. For instance, controlling the relative phase of two different oscillators, because you’re going to mix them in some way. Or simply using a slow LFO for gentle modulation.

And if your modulation signal isn’t a sine, you get serious differences.

This is Shapeshifter, with the carrier as a sine wave and the modulator at a 2:1 ratio. First we hear a sine wave as the modulator, using TZFM and then PM. Very similar (aside from the PM having to go through conversion at a lower rate and resolution than the internal workings of the module).

Then at :09 I switch the modulator to a triangle and again, demonstrate TZFM and then PM. Very different sounds there, which is the math at work.

At :18 I switch the modulator to a square and repeat. Notice TZFM with a square sounds a lot like PM with a triangle? A steady linear increase in phase is the same as a static increase in freqeuncy, and a square wave is just flipping up and down between two levels, so this totally makes sense.

And then at :26 the modulator is a sawtooth. It’s pretty awesome sounding with TZFM and nasty with PM.

I realize that doesn’t argue that Sound Semiconductor is cheating people out of something great — the TZFM just sounds better anyway. But I don’t think they should have called it phase modulation.


The Shapeshifter page is up. My general impressions of the module, favorite wave banks, three handy presets to serve as starting points, and 16 patch recipes. Hopefully it’ll be as useful for a few other people as the process was for me. That module is a monster!

I finished The Frugal Wizard’s Handbook for Surviving Medieval England (it wasn’t super long and was a quick read). It was… hmm, a popcorn novel I guess? I wasn’t blown away, didn’t have any really huge laughs or big OMG moments, kind of felt like every part of it had been done before in some way or another, and it didn’t have the immense charm of the first Secret Projects book, Tress of the Emerald Sea. But I was entertained. 3.75 stars maybe? If it’s the weak point of this set of releases, that’s totally acceptable.

Now I’ve started on Exultant by Stephen Baxter, which I picked up at a library book sale ages ago and finally realized I haven’t read it yet. I could have sworn I’ve also read other novels by this author, but apparently not, I confused it for something else. So far it’s very much Big Weird Ideas science fiction, with characters that are compelling, and I’m probably going to thoroughly enjoy it and look for more of Baxter’s work.

catching up

A few things to catch up on:

  • My parents’ visit to the area to look at real estate was a bit of a bust. They weren’t prepared for the paperwork to get pre-approved for a mortgage so the realtors wouldn’t show them properties. They did look at some manufactured homes, and actually came kind of close to deciding on one of them but then changed their minds after a second look. And they got a feel for the various neighborhoods in the area. And they got to visit with us a bit, and finally meet Lady and Yankee. Yankee was surprisingly accepting of them after the first few minutes, and even sat next to them and let them pet him about as much as he ever lets me. So next time, they’ll be able to stay with us instead of a motel, if they like.
  • I finished reading the Allen Strange reprint (Electronic Music: System, Techniques and Controls). To be honest, given the book’s reputation, there weren’t that many new insights for me. There were a few things that I had learned myself after getting into modular synthesis which the book would have accelerated, but it was all basically review for me. I’d still recommend it to a beginner or perhaps to someone not as deep into modular as I am.
    I found a little bit of it was quaint — digital audio was in its infancy when the second edition of the book was written, and that has implications not just for control, oscillators, some synthesis methods, etc. but for delay lines and especially for recording and editing. But hey, some people even in 2023 are into tape.
  • Currently reading Heir to Uncertain Magic, sequel to Keeper of Enchanted Rooms. I really enjoyed the first book, but this one isn’t quite as engaging. Next up is Brandon Sanderson’s Secret Project #2, The Frugal Wizard’s Handbook for Surviving Medieval England.
  • The Shapeshifter deep dive is just about done. I have a couple more notes to check on, then I’m ready to write it up. I’ve discovered a few more wave banks that I have good use for, created a couple more useful presets, and noted several patch ideas. My opinion of the module has only increased.
    I think I’ll be covering Akemie’s Castle next. Whether that’ll just be simple confirmation that it’s worth its 38HP, or if this is the time I decide to sell it, or if I wind up documenting my findings as I have with Synchrodyne and Shapeshifter remains to be seen.
  • Intellijel Cascadia was announced a few days ago. Just the name was teased months ago, but it was delayed due to supply chain issues. It turns to be a premium semi-modular synth of the “East Coast meets West Coast” variety. If the Minibrute 2S is the Honda Civic of that category, this is the BMW. It doesn’t make sense for my rig, but there will be people who enjoy it.


Here‘s what I’ve written up about my explorations of WMD Synchrodyne. No promises that my exploration of Shapeshifter or other modules will result in similar articles, but hopefully someone finds this useful. I know the process was very helpful for me 🙂


I’ve mostly completed the main part of the Synchrodyne deep dive. It didn’t take that long after all. I had some confusion about the behavior of CLK IN in the PLL section, but it turns out it was an undocumented change — instead of overriding the internal VCO, it is a logical OR with the output of the PLL going into the filter, which the designer thought was more interesting. It’s available on the expander module, but since they stopped building expanders before the last batch of Synchdrodynes he went ahead and put it on the main module. There are a couple of things I want to try with that.

Overall I’m much more in favor of Synchrodyne than I was before. The key thing I understand now is its tracking behavior — how to make it stable, and how to carefully make it unstable and take advantage of that instability for added texture and even FM bell-like pings. But also the usefulness of the main folder, and several patch ideas for the filter as well as the PLL and VCO (e.g. clocking Drezno in ways that add noise to a signal running through it).

With the official release of Serge GTO, I thought I’d better get going on that Shapeshifter deep dive and make my decision about keeping or selling it, or risk them selling out of the first batch.

My doubts in Shapeshifter were based mainly on the fact I was using so few of its features, and maybe a different design of complex oscillator would work — or just rely on my other oscillators to handle TZFM duties.

So one night I did some tests and confirmed my biases: the wavetables are mostly garbage (*), the tilt sounds harsh and unpleasant, the sync sounds harsh and unpleasant most of the time, the bets combo modes are the ones I could do with Mystic Circuits Ana, the chord mode isn’t as nice as other modules, and so on. The wavefolder is nice. The sines are SUPER pure and clean and the TZFM is by far the smoothest and cleanest of everything I have, but that’s more of a neutral fact than an advantage to be honest.

(*) I prefer wavetable banks to have a progression of shapes or spectra from one end to the other, not an unoragnized collection of cycles with little relation so that scanning through it sounds random. The latter style of bank is very common, but leads to a tedious hunt for sweet spots. If you have a simple wavetable oscillator like Kermit with one bank like that it can be fine (if the oscillator otherwise has good character); if you have 128 wavetable banks and 103 of them have no organization and 50 of those have not one single pleasant cycle among them, it’s tedious.

I was thinking about the new wave of TZFM-capable oscillators that use the very capable newish SSI2130 VCO chip. There are a variety of them, with different designs and features built around the core, and generally they sound pretty great. Perhaps the flagship of those is the Cosmotronic Vortex, a dual oscillator that features two variations of the oscillator with different wavefolders, two different wavefolders, ringmod, a nice FM bus for both exponential and linear FM, and a smart and flexible overall design, and is exactly the size of Shapeshifter.

Or, I could go with a Rossum Morpheus z-plane morphing filter, which makes for a pretty fantastic resonator according to a few adventurous souls, and still have room for one of the smaller 2130 VCOs such as Shakmat Banshee Reach or Befaco Pony, or some other thing instead. But I decided I’d (A) play with Instruo Cs-L in VCV Rack, and (B) sleep on it.

I woke up early because it was a bit too warm, and decided to fire up Shapeshifter again… and stumbled into a couple of amazing things fairly quickly.

  • the Harmo3 wave bank consists of smooth, clean sines advancing through higher and harmonics in a smooth, clean way. This is really nice for things like FM or combo modes.
  • the delay! I really have not played with this enough. The delay is clocked by osc2’s frequency, is mixed into output 1, and the feedback level also serves as a mix level. If you set osc2 to LFO rates it’s a “normal” rate delay, but at audio rates it acts as a resonator…
  • Osc2 still works as an oscillator with the delay engaged, and phase and waveshape do not affect the delay. So you can phase modulate osc2 from out1 (which includes the delay repeats!) — whether Osc2 is running at audio or LFO rates — or bypass the oscillator and use out1 for a wavetable lookup, and patch that in stereo.
  • You can also FM osc1 from out2, including the phase modulation you’ve applied… and if you’re running osc2 at audio rates, the resonator feedback will smooth out the usual weird harshness of that kind of cross-modulation. You can also use combo modes, chords etc. all to pretty great advantage. And that Harmo3 wavebank is really nice for sweeping the harmonics that are fed back through a resonator…

I need to experiment more in this area, but what a difference these discoveries can make. I’m sure Vortex is cool but I will be keeping the Shapeshifter, thanks.

Exploration of Shapeshifter is going to take a bit of a different format from Synchrodyne; the manual for Shapeshifter is more complete (and up to date) and it’s easier to understand both technically and intuitively what’s happening with it. It’s just that there’s so much possibility there, I wound up leaving a lot of it inadequately explored.