Ten days ago I wrote a blog entry about signal routing and the inherent difficulties encountered as an audio system becomes more complex. In that entry, I explained that I’m trying to figure routing out so I can start learning about managing the quality of the audio signal for recording. I’m back today with a note about how my lessons for understanding audio levels are progressing.

First of all, I have a potentially “hot” signal leaving my Levit8 mixer and going into my Expert Sleepers ES-8 audio interface that sits between my modular gear and my DAW. Once in Bitwig, I can have multiple simultaneous audio channels from my modular gear for recording, but how do I modulate those signals so they don’t clip? In order to answer that (possibly incorrectly) I watched a number of videos regarding mixing and something called the K-System. Instead of regular VU meters, I’ve opted for the K-System that was created by Bob Katz. I’m not going to explain why today, but I’ve come to the conclusion that it’s the metering system for me.

Once a signal enters an audio channel in Bitwig it typically clips after I’ve armed the channel. Back at the Levit8, I need to attenuate the signal down, way down and super low in some cases. From there I throw a Fabfilter Pro-L Limiter on the track and adjust the output until I get an average reading of 0 dB on the meters. This feels like a mad science where I’m certain I’m missing something totally obvious, to everyone but me. I’m yet to tackle where compression and EQ come in to play.

There is a bit of a dilemma here as I actually have two workflows I have to move through. On the one hand, I have a bunch of mono outs from three Levit8’s, a Mutant Hot Glue, a Blinds, and a floater I can plug into the Planar in my skiff or into the Moog Mother 32. Using this flow I take the outs into my Mackie 1202-VLZ4 and that signal is fed into my Universal Audio Apollo Twin USB which drives my audio monitors. This setup is great for just turning on the synth with no intention of recording anything and getting right to patching. It also allows me to leave the synth off and work just with Bitwig or use the Apollo for playback of audio from videos or other PC-based media.

On the other hand, if I want to record what I’m making on the synth I have to take those outs from above and feed them into my ES-6 and ES-8 modules from Expert Sleepers which are then delivered via a USB connection to my PC (Windows 10) and then to the Apollo Twin Duo. As I said in the previous entry, I require ASIO4ALL to make this work. I’d like to rely solely on the ES-8 and its helpers the ES-6 and ES-3 and feed that signal into the Mackie, but then I’d still have the issue of where to send my PC audio and how? Maybe a larger mixer?

One of the pleasures of Eurorack synthesis for me is firmware updates. With them comes the opportunity not only for greater stability but added functionality. Ornament & Crime is an open-source platform that has grown from a single function to 13 amazingly intricate and sublime routines. One of the developers who has contributed much to the Ornament & Crime module is Timmy Churches, apparently from Australia who on speaking about it had this to say, “O&C isn’t a traditional product designed, manufactured, and sold by a single entity — it’s a post-capitalist artifact of the after-hours sharing economy, and thus mash-ups and overly complex pastiches are to be expected.”

With this in mind, it is obvious to me that we will be seeing ever more complex modules coming out of this sharing economy. This portends exciting times for our future in that those of us bitten by this Eurorack bug will forever be finding deeper modules made the more so by community involvement with extending functionality using open-source platforms.

I have a special affinity for my modules that do employ firmware updates as there is also the possibility of alternative firmware versions that can radically alter the functionality of the device. Case in point is many modules from Mutable Instruments that support “Parasites.” These parasites often but not always leave the original firmware mostly intact and tack on some new functions that make the module far more valuable to their owners.

On the other hand, there exists the opportunity to get a module to market sooner if the maker can start distribution of the hardware platform early and then involve the community to help shape the overall function. To that end, we have modules such as the Orthogonal Devices ER-301 and the Winter Modular Eloquencer that were put into artists’ hands early allowing testers to feedback with the developers to fine-tune things and respond to community requests for ease of use or added functionality.

Today was the day that the crew behind Ornament & Crime released version 1.3.0 of this module’s firmware now it’s time to open up the 47 pages of dense documentation to learn what’s new and how to use it. Big thanks to Patrick Dowling (aka PLD), Max Stadler (aka mxmxmx), and Tim Churches (aka Bennelong.bicyclist) for their dedication to this project and for making one of the great contributions to Eurorack synthesis.

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!