Video of a practice session with the third iteration of ‘Drawing In’.

Audio produced by:

• Behringer 2600
• Coron Drum Synthe RDS
• Korg MS-10
• Korg MS-20
• Quasimidi Rave-0-lution 309
• Waldorf Rocket
• Yamaha CS-5
• Yamaha CS-15

I count seven sequencers currently in use in this version.

Sometimes you seem to leave messages for your future self. I found this scribble in a box of 20-year-old documents I was sorting through.

In the moment of your birth you began to learn to breathe, inhaling air, exhaling; crying at first; it was as new to you as you to the world. But you had an instinct for it. What didn’t come naturally came before long through learning — when to breathe and when not to breathe, and when to breathe in and when to breathe out. I assume this is all true, because you’re still alive.

And yet the strange thing is, you’re not happy. I wonder why we don’t have the same instinct for happiness we have for air. We know somewhere that once a moment’s joy is in us we have to let it go again lest it turn stale and choke us . . . yet it seems difficult to turn this knowledge into action . . . as if we spent our days turning red in the face and moaning about letting the moment’s breath go.

So learn: Each moment of joy is that moment’s joy; it cannot be grasped without halting the flow of happiness by which you live. Breathe it out, use it for speech or for song, but at all events, do not seek to squeeze it within you and suck up more without letting the old air go. Learn to breathe again.

Happiness is like breathing. You cannot hold a breath for long lest it turn stale and choke you, but you learned to breathe it seems . . .  You must also learn to exhale this moment’s happiness and allow the next moment’s joy in.

(Update: Since people seem to like it, here it is as a printable PDF.)

I got this, ready built, because I needed a simple switching function for another Eurorack module and it was being sold cheaper than any actual switching module or combination that should do it, and hey another sequencer will always be handy. So here’s some notes:

• There’s no start / stop button(s) or input(s). It can be stopped by plugging a dummy plug into the clock input but that’s yer lot. This seriously restricts its utility because you can’t easily get it to work in sync with other devices or even start it manually at a desired time. (But it occurs to me that you could mount a switch on the end of a dummy plug?)
• The sequencer doesn’t seem to respond to V‑Trig signals at the clock input in the way I’d like; that is, it resets to 0V but most input sources I use start high. Inverting the input fixes that, but it then starts out of step so anything it’s controlling may need to be reset to the previous step.
• The clock input is a bit finicky in other ways; not all clock signals will drive it; perhaps it needs a slightly higher voltage. The Doepfer dividers manage it, some other modules don’t. (This is independent of polarity.)
• Sometimes it steps the outputs without stepping the LEDs but I haven’t worked out how that was happening, and by the time I got it to work it wasn’t happening any more.
• There is a manual available from Erica but it’s a build-it manual and is very short on actual functional description of the finished module, so all the above points had to be worked out slowly and uncertainly rather than just read, and remain a little tentative.

With that worked out, it’s doing the job as intended but if I’m going to use it for the usual range of purposes one might use a sequencer, a useful mod might be to put a switch on the internal clock signal. And a reset switch to start it high if need be. For the time being I’m using an external inverter on the input.

(Update, 2024-09-17:) One other unexpected detail that’s causing confusion is that it seems somehow to be passing an extra pulse through to GATE OUT from CLK IN at the end of an active step. In other words, either an active switch appears to produce a trigger pulse at the start and end of the step, or, since it happens at the end of any sequence of active gates too, the subsequent inactive switch also produces a pulse. This does not happen when driven by the internal clock. For current purposes this is kind of useful if you know it’s there but I can see it being a problem otherwise.

Further investigation shows something about the nature of the issue. The connected devices (sequential switches) return to state 1 (out of 2) under specific conditions. They don’t respond in that way to either the Erica’s internal clock (GATE OUT with no input), or to the direct input signal (which as you may recall is inverted), nor to the pre-inversion signal, nor to the signals as passed through the Erica’s CLK OUT socket, nor to its GATE OUT when the input is not inverted. I should note that all this still obtains when the output devices have nothing connected other than the various step inputs tested.

After much confusion I was finally able to find the output pulse with the oscilloscope. This is 6V high and about 2µs wide at the top. Enough to trigger most output devices. (Though not all.) It is produced when a new input step occurs, but only if the next gate switch is off.

So it’s a combination of the NOT gate (Doepfer A166) and the Erica. I imagine this is to do with different response times in different devices’ components.

My MS‑10 has been behaving a little poorly recently, with the EG release time fluctuating to a gradually growing degree. So I’m going to have a look at it. First, have a look at the service manual as this failure seems likely to be a misbehaving capacitor. And yes, there’s a 6µ8 Tantalum cap (C35) on the release stage, so that’s the main suspect. I hear some bad things about Tantalums, but I’ve never had one fail before. Anyhow, I did have the thing apart for cleaning when I got it but didn’t take the PCBs out as it involves a fair bit of unscrewing things. So this is my first look at the relevant board (KLM-126c).

(Picture taken after repair.)

Checking C35 in-circuit, difficult to be certain but nothing obvious wrong.

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Quick note about a quick repair.

The SQ‑64 is a simple-looking but rather complicated digital sequencer which can receive and send CV/Gate/Trigger, Korg Sync, and MIDI signals, which is intrinsically a 64-step sequencer and which can chain sequences etc. It’s handy for translating analogue timing signals and setting up sequences for MIDI devices which can’t take a simple external clock, and so on. It has some limitations as a controller of analogue synthesisers however, but that’s not the topic today.

This SQ‑64 was I think bought new about two years ago, not long after they came out, and has developed a fault, so I’m going to investigate. The fault is that the eighth top row sequence button is activating intermittently without being pressed, which adds unintended gates to a sequence and prevents the user accessing additional functions in some modes because this button is interpreted as being pressed and having priority over other things, somehow.

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I had occasion a few days ago to install MacOS 10.12 on an old laptop, and encountered an error message at what seemed to be the end of the process. Spent half an hour trying to see whether this was a known problem. It’s a little confusing because this was a fresh installation rather than an upgrade, and I found several references to failure messages in upgrades and ideas for how to fix the problem, as this was apparently quite common with 10.12, but not for new install.

Armed with a few very unlikely seeming ideas I restarted the machine intending to wipe the drive and start again . . . and then realised that the error message seemed to have come up at the point where the installer tried to load a message to say, we’re done for now and please restart to complete the installation. And it completed the installation. This took a while but it’s now up and running.

(I say it took a while but really it took far less time than it used to, swapping floppy disks in and out. It just seemed longer since there was nothing to do but watch.)

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