Getting started making sounds in dexed from scratch is easier than you might imagine. Let’s make our first custom sound in dexed, using the knowledge we’ve gained about the User Interface (UI). As we build the sound, we’ll observe how the changes we make in the UI affect the sound we’re building, and at the end of the session, we will have a usable, albeit simple sound to use in our library.
Put the keys in the ignition and start up dexed, either in stand-alone mode or by placing dexed on a track in your DAW, and press the [INIT] button in the lower left-hand corner of the UI. This creates an initialized patch using Algorithm 1 in dexed. Here, you can play a few notes if you wish. You’ll note that this is possibly one of the most boring sounds you have ever created, on any synth, in history. It’s a purse sine wave tone that, giving it some credit, can be a useful diagnostic on rare occasions. It is a testament to a LOT of technology and engineering development. That said, we want to make some changes right away and start having a little more fun than playing sine waves.
In our first, simple patch, we’ll just work with two operators, so our first step will be to turn off Operators 3, 4, 5, and six by toggling the switches to the left of each operator number. The switch in the “up” position turns off the operator.
Let’s make our test sound a little more tolerable next. Because I spent a large part of my career engineering synthesizer software, I’ve heard a lot – more than you want to know – of digital sine waves that have abruptly enveloped sine waves. It can be fatiguing – so let’s get rid of that fast release on Operator One and eliminate that slight “snap” at the end of each note. Adjust EG Rate 4 in Operator 1 to 60 or so, around “1 o’clock”. Note that we also have feedback in the status display of dexed on the lower left. We’ve got a sine wave with a little release envelope now, which is much less tiring, so let’s move on to the next step.
While we’re working through some of the simpler patches in this series, I’ll be using an oscilloscope plug-in to visually confirm what my ears are telling me as I work with dexed. This isn’t a requirement at all, but sometimes, especially when attempting to teach, showing visually and coupling that with what you’re hearing audibly makes a difference. I’m using Melda Productions MOscilloscope on the output bus of my DAW in this example – it’s one of several free Oscilloscope VST/AU plugins that you can use if you wish (Check the Resource List below). We can use the oscilloscope to see that we’re only generating a sine wave as we play notes across the keyboard.
So far, we’ve got a two-op FM patch with a short-release envelope programmed, but there is no contribution to the sound from Operator 2. Let’s change that. Reviewing our Algorithm diagram, we can confirm that only Operator 1 and Operator 2 are active. Additionally, we can see that the output level of Operator 2 is at zero – this is why we can’t hear its contribution. Our goal is to make a sound that is simple yet interesting, while also showing the effects of Frequency Modulation. A simple way to do this is to change the frequency ratio of Operator 2 because as we see from our Algorithm Diagram, the output of Operator 2 modulates (it’s the modulator here) the output of Operator 1, the carrier. Change the Coarse tuning ratio of Operator 2 to the value of 2, which will double the frequency of the operator. This will make its output 1 octave above Operator 1.
Still, there’s not much joy sonically despite these changes. That’s because the volume level of Operator 2 is still at zero, so effectively it is not making a modulation changes to Operator 1. We’re going to raise the output level of the Operator to 70 by turning the Level knob. What we hear now is a sine wave that contains a little more harmonic content, and what we can see on the oscilloscope is a waveform that approximates a square wave. Now, things are getting interesting. What we can remember here going forward is that a quick approximation of a square wave in FM can be generated by modulating the carrier wave by the second harmonic of that carrier, which is exactly what we’ve done here.
Now we have a square wave synth, a little more sonically interesting than a sine wave synth, but still not much going on. To my ears, synthesis gets interesting when waveforms change over time, not just change shape. Yes, changing a sine wave to a square wave in dexed is a feat of modern engineering, but we’re going to take it to the next level. Let’s change the waveform over time by changing the level of FM that Operator 2 is creating using an EG. In Operator 2, change EG Level 3 to zero. This should change the output level of Operator Two to zero again because we’ve changed the sustain level of the Envelope to zero. Next, adjust EG Rate 3 to 40. What we’ve created is a time-variant waveform – one that changes from a square wave to a sine wave following the envelope that we have programmed in EG2. Let’s pause and congratulate ourselves on creating our first FM voice. Play it. Enjoy it. This could easily be a subtle bass sound to use in your compositions.
Let’s make some final adjustments to make it a real, playable voice. Carefully press the PARM button – don’t accidentally press INIT because then we’ll have to start all over – adjust the Pitch Bend Range for both up and down to 2. Also in the Modulation Matrix on the right of this pop-up display, set the first switch to the right of “Wheel”, which routes the Mod Wheel to control the output of the LFO to Pitch, to “On”. Testing our sound again, we have Pitch and Mod wheel control over our Subtle Bass sound. Let’s store it next.
Storing our edits in dexed is fairly straightforward. Close the dexed Parameters window by clicking the “x” in the upper left corner, then press the STORE button. You’ll see a pop-up window again, allowing you to name the voice -I selfishly recommend “Subtle Bass” as a name. There’s also a field to select the target sound to overwrite within the current cartridge, create a new cartridge, and the option to store the sound as a program in your DAW session. I tend to keep all of my synthesizer sounds separate from my DAW sessions, so I would select “Store program and create a new copy of the .syx cartridge”. There’s also an option to open another cartridge and store the sound in that new, External File (another cartridge .SYX file you select). All the bases are covered for storing this sound within dexed.
I’ll make a recommendation for a few experiments and adjustments to try while you wait for our next programming session using “Subtle Bass”. You can change the modulation from Pitch Modulation to Amp Modulation – from vibrato to tremolo – by changing the switch in the PARM display for the Wheel to disable Pitch and enable AMP. This, coupled with increasing the A Mod Sens in Operator One will generate a Tremolo effect. Additionally, you may hear a small “pop” at the start of each note, especially on lower notes of the keyboard, This tends to happen in digital synths when a full-range waveform hits the Digital Audio Converter (DAC) and can be eliminated by adjusting EG Rate 1 to 85 or lower – this smooths the Amp EG at the start of the note. Finally, more drastic FM effects can be achieved in this sound by adjusting the Output Levels of Operator 2, and/or changing the Coarse Ratio. These are just a few starting points – clearly there are tons more that are available in dexed.
So, we’ve created our first FM sound in dexed, and again, congratulations. In our next installment, we’ll add another voice to our custom-programmed CART, adding another level of FM complexity to our programming skills. As always, thank you for reading.
Resources:
- The dexed plug-in:
- The sounds included with dexed:
- SoundEngine’s Rebuild: dexed (Sounds, documentation, and tutorials):
- Our custom programmed banks – Flywheel& Crankshaft: dexed:
- Our dexed series so far:
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