6 – Vocoder Arp Machine

I was looking through eXode’s fabulous collection of free patches and combinators in his massive synthesis refill (available from the Propshop’s Free Refill Download Page – A must have for anyone who is looking for a great collection of new sounds!) when I came across a few patches that were hidden away with (arp) in parentheses after the patch names. Being one who loves a good arp sound I started to delve a little deeper into how it was put together. So this became the inspiration for this project. It fuses an arp with two thors — one for the modulation and another as the carrier, and both Thors feed through a Vocoder to the final output.

Now taking things a few steps further, I decided to deviate from what eXode did and add on a few modifications. Firstly, the sounds I used were completely my own (I didn’t want to copy eXode’s brilliant work). And I then took things another step further by assigning parameters to the Combinator rotaries and buttons. This way, you can use the Combi as a performance tool as well. And you can experiment with your own Thor sounds for the carrier and change the way the vocoder operates by toying with the Thor synth parameters, creating your own endless variety of Arp Vocoder machines.

So this is a bit of a mashup, being a Combinator that plays just fine as it is, or used as a template where you can drop in your own Thor patches. Finally, it can be used in live performance, since all the Combinator parameters are assigned for this purpose. After all, the more flexible the Combinator is, the more use you will get out of it.

The project files can be downloaded here: vocoder-arp. It contains an .rns file with a single Combinator which is pre-programmed to most of the major parameters you’ll need to adjust the Filter Frequency, Arp and Vocoder parameters.

Setting up the Vocoder Arp Template.

1. First, create a Combinator, then inside the combinator create a 6:2 Line Mixer, Thor, RPG-8 Arpeggiator, BV512 Vocoder, and then holding Shift down (to disable auto routing), create another Thor. Flip the rack around and route the bottom-most Thor’s 1 Mono / Left Output to the Modulation input on the Vocoder. This is the basic setup for the arped-up vocoder. The first Thor in the Combi is the carrier, and an Arp is tied to this Thor. In other words, this is the main sound going into the Vocoder. The second Thor in the Combi is used to Modulate that Carrier sound through the Vocoder.
2. Next, holding Shift down, create two Spider CV Merger/Spliters below the Combinator’s Line Mixer. Then hold Shift down and create a Matrix at the bottom of the stack. Set the steps to 4 and the resolution to 1/4th. Switch the Matrix mode to Curve, flip the rack around to the back and switch the curve mode to Bipolar. Then flip the rack around again and set up a curve pattern so that step 1 and 3 are +64 and step 2 and 4 are -64.



3. Flip the rack around and on the first Spider connect the Arp Note CV out to Split A in and the Arp Gate CV out to Split B in. Connect one of the splits from Split A to the Carrier Thor’s CV in. Then connect the inverted split from Split A to the  Carrier Thor’s CV1 Modulation input. Connect one of the splits from Split B to the Carrier Thor’s Gate input, and another split from Split B to the Carrier Thor’s CV2 Modulation input.
4. On the second Spider connect the Curve CV output from the Matrix to Split A’s input. Then connect one of the splits from Split A to the Split B input on the same Spider. Connect another split from Split A to the Vocoder Hold input. Connect the third split from Split A to the Carrier Thor’s CV3 Modulation input. Then connect the inverted split from Split A to the Arp’s Velocity CV in. on the Spider’s Split B, connect the inverted split to the Arp’s Octave Shift CV in. That just about does it for the CV routings. Luckily you can see the Combinator for yourself when you download the project files, because that was a mouthful. But it sounds more complex than it actually is.
5. Moving to the Arp, and while you’re on the back of the rack, remove the CV cables from the Mod Wheel and Pitch Bend CV out. This way when you use the Pitch Bend, it will only affect the Thor Carrier’s Pitch Bend setting. Now flip the rack around again. Set up the Arp with an Octave Range of 2, and Insert set to Low. On the Vocoder, set the Attack to 8.



6. Now we move to the Combinator programming. Click the Show Programmer button and enter the following settings:

   For the Thor Carrier:

   Performance Controllers > uncheck the Mod Wheel

   Rotary 1 > Filter 1 Freq: 0 / 127

   Rotary 2 > Amp Env Attack: 0 / 25

   Rotary 2 > Amp Env Decay: 50 / 27

   Rotary 2 > Amp Env Release: 18 / 27

   Button 1 > Filter 1 Env Amount: 28 / 100

   Button 4 > Delay Sync: 0 / 1

   For the Arp:

   Rotary 3 > Gate Length: 10 / 115

   Mod.W > Synced Rate: 5 / 15

   For the Vocoder:

   Rotary 4 > Shift: -20 / 20

   Rotary 4 > Decay: 80 / 127

   Button 2 > Band Count: 3 / 1

   For the Thor Modulator:

   Performance Controllers > uncheck the Pitch Bend and Mod Wheel

   For the Matrix:

   Button 3 > Pattern Select: -1 / 0





7. Now flip the rack to the front now, and load up your favorite patch in the Thor carrier. Usually a bright lead will work best, but experiment with any sound you like. You can take a look at how I programmed the Thor in the image below. I won’t go into all the settings that were used. You can pretty much see them here. However, there are some core settings that are needed in the Modulation Bus Routing Section (MBRS) in order to have the Combinator function properly. On the right side of the Bus, create the following routings*:

   CV In1: -32 > Del Rate

   CV In2: -56 > Del ModAmt

   CV In3: 50 > Amp Pan



8. Add a matrix below the Combinator so that it is playing the Combi. Then enter a pattern and hit play. This tests out the sounds of the Combi as you experiment with your Carrier and Modulator. For the modulator, you usually want something atonal or heavy on the noise. Unmusical is best. Droning is perfect to affect your carrier signal. This is the fun part where you toy with the Thor until you get something you like. The nice thing is that you have a wide variety of sounds to choose from using the Thor synth.

An explanation of the Combinator Programming

Pitch Bend: This affects only the Thor Carrier as you would expect a pitch bend to operate.

Mod Wheel: The Mod Wheel controls the Arp’s Synched Rate from 1/4 to 1/128th. You can use this as a performance controller to create some interesting arp variations. Let your ears be your guide on this one.

Rotary 1: This controls the full range of the Filter 1 Frequency from the Thor Carrier. Fully left and the filter is closed, fully right and the filter is fully open.

Rotary 2: This controls the Amp’s Attack, Decay, and Release from the Thor Carrier. Fully left and you’ll have very short ADR setting. Fully right and you’ll have much longer ADR settings

Rotary 3: This controls the Gate Length on the Arp. This is one of my favorite settings to play with because it can drastically alter the sounds coming from the Arp. Fully left and you have very short note lengths where the notes are staccato. Turn the knob fully right and you’ll have very long notes – to the point where the notes blend into each other much more smoothly (legato).

Rotary 4: This controls the Shift and Decay of the Vocoder at the same time, affecting the phase of the sounds you hear. This actually shifts the filters of the Vocoder’s Carrier signal down (turning the knob left) or up (turning the knob right). This can be a fun parameter to play with, and you’ll have to experiment to hear what sounds pleasant to you.

Button 1: This controls the filter envelope for the Thor Carrier’s Filter 1. Use it as a sound mode switch, and as with the Rotary 4, you’ll have to hear what sounds pleasant to your ears.

Button 2: This adjusts the band count of the Vocoder. When off, Vocoder has 32 bands. When turned on, the Vocoder has  8 bands. One note about this button: it takes a little time to catch up with itself when you alter the bands. So this may not be great for performance, and you might want to keep this button either on or off. But it’s great fun to test out your sounds through different band counts. If you don’t like these settings, you can change them in the Combinator’s Programmer to switch between any 2 bands you like.

Button 3: For lack of a better word, I named this button “Slider” — as it sounds like the notes from the Arp are being slid on the last beat of the bar. In addition, the Slider button will Pan the sound from left to right in the stereo field based on the Panning settings that were set up in the Carrier Thor’s MBRS. Remember that CV3 in we set up in the Carrier Thor? That’s affecting the Pan of the signal. In addition, the Matrix we placed at the bottom of the Combinator Device Stack is waving the sound up and down like a pulse wave. With a resolution of 1/4, the signal is synched to the 4 beats of a 4/4 tempo. But the Slider does a bit more than that. It also controls the Hold parameter of the Vocoder via CV. This means that on the fourth beat of the bar, the Vocoder is held for the duration of that last beat (one full 1/4 note). Finally, it also controls the Velocity and Octave Shift of the Arp. Yep. One of those spiders and the matrix were set up to perform a simple switch. But I thought it was a pretty cool way to affect the signal. When you turn the button on, it starts up the Matrix pattern to control everything via CV. When you turn it off, the Matrix doesn’t play any pattern at all, essentially shutting down the CV triggers.

Button 4: Finally, we have a simple switch which either keeps the Global delay of the Thor Carrier free running (when left off), or synched (turned on).

---

* One note about switching the Carrier Thor’s patch. If you switch the patch, you’ll have to remap the settings in the Modulation Bus section for the CV1, CV2, and CV3 sources (all the settings on the right side of the Modulation Bus section). Otherwise, the Delay and Slider functions won’t work properly. Alternatively, you don’t have to switch the patch at all. You can play with the settings in the note / global sections of the Thor until you come up with a sound you like. Point is that since this Combinator is so heavily programmed, switching patches requires a little more tweaking than normal.

Switching patches in the Modulator Thor won’t require any remapping because none of its parameters are used externally.

Any thoughts on this setup? Any ways you can see to improve it? Let me know what you think. . .