Like Terence McKenna once said, “The further you go the bigger it gets.” If you begin your own exploration of the world of modular synthesis you will learn that you have likely bitten off more than you want to chew. Case in point, tuning, and calibration. After upgrading firmware there is often a requirement that the module must be re-calibrated. This is typically done by sending a 1 volt and a 3 volt signal to the device that signifies particular notes such as C2 and C4.

On the other hand, there is my Ultra Random Analog (URA) from Steady State Fate which is a random voltage generator. While following a tutorial for it I just couldn’t get the same effect out of it in the same way, as what was being shown in the video. At the time it would have been easily explained that I simply wasn’t understanding much of what I was trying to learn. Over on Muffwiggler, I found a conversation about other units that weren’t calibrated correctly and it read like this was exactly my problem. I did the best I could but was very uncertain about what I was doing.

Fast forward some months and now armed with a better bit of knowledge I can tell that my URA is still not calibrated correctly. I first need to remove the module from the rig but leave it plugged in as it will need power to it in order for me to make the required adjustments. To do this I’m lucky enough to have an oscilloscope from Mordax called the DATA, it’s a great Eurorack module everyone should own. There are three things that require calibration on the URA a clock that sets a gating frequency and two noise sources that should fall between particular voltage levels. The clock for the gate is calibrated by listening and choosing a timing that works best for the owner of the module. The other two calibrations are a bit more involved.

This is where the oscilloscope comes in. I have to send a particular signal out of the URA into the oscilloscope that is set to sample the incoming signal at 10ms and measure the voltage from +10 volt to -10 volt. From the first output, I need to adjust the left pot (the little round things) you see above on the sides of the chip. I have to be careful to not turn too far as these are fragile and easily damaged. I’m looking to set them so they are producing brief peaks of +10V and -10V on the oscilloscope. When I’m done with the first pot I move the cable to the other jack and start measuring its signal. Somehow I missed this part of calibration on the first pass those months ago, as the second channel is off by a mile. By the way, while the miniature screwdriver is touching the pot the signal is being skewed so you make a small adjustment and remove the screwdriver to get a clean measure and then go back to it again until you get the range tuned in.

Fortunately, this isn’t a common thing that has to be done on many modules, but having the tools and determination to get it done lets me know a little bit more about this complex hobby that has me feeling like a mad scientist from time to time. I think the writing is on the wall that somewhere in the not-too-distant future I’ll be soldering my own synths so when a module needs a simple repair I’ll have the confidence to do that too.

No blinky lights, no patch cables, no electricity. The rig is cold. An emergency at our office required me to forego Sunday morning playtime; then, about an hour after getting to the office, the electricity went out for a large part of our neighborhood. As I’ve pointed out in a previous post, this is an ADDAC Monster case with 10A of power on both the +12V and -12V rails. The case is 197hp/21U and full, while I have another 783hp of cases that are slowly being filled up too. After seeing Colin Benders’ new rig he’s having built by Jan Willem Hagenbeek of Ginko Synthese, I’m getting itchy fingers to discover the ergonomics he’s about to explore!

Audio routing is no easy task; as a matter of fact, this is one of the most frustrating parts of learning how to work with audio hardware and software. So, instead of working up a patch, I’ve just spent far too much of my night aggregating various sound interfaces together. The objective was to get the Expert Sleepers ES-8 audio out of the module without having to go mono out using one of the jack ports but to have stereo out handled by the USB. Good luck finding documentation on this. Piecing things together, I knew that ASIO4ALL might be able to play a role; I’m on Windows 1o and understand this is easier on a Mac. So what I now have set up is 10 CV/Audio inputs and 16 CV/Audio outputs shared between the ES-6, ES-8, and ES-3. The FH-1 on the right is the interface from my Roli Seaboard Rise into the modular rig; I’m still lacking confidence in how this works, too. Finally, I have the ins and outs mapped within Bitwig, but it is not elegant and requires a bit of hunting for which ports were which among over 34 aggregate in ports and 30 out ports. Next up, I need to figure out how to get a nice clean signal out of my final mix and into my camera so I can record audio of an appropriate quality, befitting the setup and investment in this system.

I do currently have a problem with this setup. In Bitwig, when monitoring or recording audio I’m getting noise in short bursts from time to time. It might not happen for minutes, and then there’s a short two or three-second burst. Reading about aggregating devices, it seems it could be a buffer issue where the weakest audio interface in the chain is the culprit. So, maybe I have to revert to a different configuration. Sometimes, you feel incredibly helpless trying to figure out a setup that might be unique in all the world to you.

No audio file or patch here – yet. This morning I connected my Leafcutter John contact mic to a finger piano and fed that into the Mutable Instruments Ears module so I could record a short sample into the Orthogonal Devices ER-301 Sound Computer. After loading the sample into the Granular playback unit of the ER-301 I was able to stutter and pitch shift the sample. I ran out of time before I could get to the next exercise of using the finger piano fed into the envelope follower of Ears to modulate the playback of the sample, so tonight I’ll make an audio clip and post a new “Patch Of The Day” as opposed to this “Photo Of The Day.”