VCVRackTutorial: The Turing Machine


The patch file: http://cornwarning.com/xfer/VCV/TuringMachineExample.vcv

Audio Example: http://cornwarning.com/xfer/VCV/TuringMachineExample.mp3

The two implementations of the Turing Machine Sequencer — in the case of this patch, the one from the Skylights plugin — are not immediately understandable without doing some reading of manuals, which is never anyone’s favorite activity.

Turing Machine sequencer have a property that is one of the best about modular synthesis (or in fact music in general) in that it takes a single simple idea and implements it in a way that can have surprising and musically useful results.

There’s a full document describing what the Skylight folks implemented here, but I think I can describe it very simply.  If you look at the byte symbol above, it shows how it is comprised of bits.  A particular sequence in the Turing Machine uses this byte (or 16 bit word, maybe) in two ways.

  1. The bits are rotated in the buffer.  And by ‘rotated’ I mean that each bit is shifted left, and the last bit on the right  is placed in the leftmost bit location.  This makes sense if you visualize it physically. If you had a row of black & white marbles, you take out the rightmost marble, and place it in the leftmost position, shifting all the other marbles right one space.
  2. In computing a byte is two things: a collection of bits, and the representation of a number in the range of 0 and 255 (or often, one of the ASCII characters).

The Turing Machine Sequencer uses those two representations to generate a pitch and a gate signal. The pitch is the numeric value of the byte, and the gate signal goes from zero to one when the rightmost bit is one.

That’s all that really happens, except for what the LOCK knob does.  When the knob is fully counter-clockwise, every time the sequencer receives a clock, every bit in the sequencer’s byte is replaced by a new, random value.  When the knob is at 12 O’Clock, half of the bits are randomized.  When the knob is fully clockwise, the sequence is locked, and none of the bits change.

So when you use the Turing Machine as a sequencer you have a choice between an always changing random sequence, an unchanging sequence, and a sequence that changes gradually over time.  This example patch comes with a locked sequence that sounds like a classic analog sequencer patch from Kraftwerk or Tangerine dream.

The output of sequencer is a tunable combination of chaos and order. It follows a very musical paradigm.  If the LOCK knob is somewhere around 3 O’Clock it means that the sequence playing changes very slowly a note or two at a time.

It also has one of  most charming features of modular synthesis: Because of how the pitches and triggers are generated, the pitches and triggers have a deep structural relationship.  A change in underlying data byte changes both the pitch and trigger in a predictable way. Well, mostly predictable, as it does it’s magic by random, probabilistic bit flipping.

When two things in music have that kind of relationship, where they’re both tied to different views of the same input, it’s something you can hear.  The sound of the SkyLights Alan Turing machine is the sound of that relationship.

Another about this patch is the quantizing setup of the pitch output of the Turing Machine:

The pitch coming out of the Turing Machine changes at every clock step, so I run it through a sample & hold triggered by the gate output of the Turing Machine.  This means that the note only changes when a new note is triggered.  Then it’s quantized by VCV Scalar.  I’ve selected notes that are a sort of 5 note scale, but different than the standard pentatonic scale.  This is followed by a Fundamental Octave module, that transposes up or down by one or more octaves.

This is kind of a standard setup for most sequencers that I use, because I want things to add up musically, and I want one pitch per note. You can certainly bypass the sample & hold and go directly from the sequencer to the Scalar Quantizer , if you want the effect of the note pitch changing as it decays.

Unreleased Aphex Twin, Warped in Ableton Live

By now, people who care about the music of Richard D. James, aka Aphex Twin, know about how he dumped 175 (and counting) unreleased songs on Soundcloud. Like everything he’s done its a body of work that is at turns beautiful, frustrating, and obtuse. The majority of the tracks seem to be Aphex-esque techno and acid house, which is to say his unique combination of standard drum patterns with melodic flights of fantasy and piss-takes.

I had the idea of DJing with these tracks, and when I say ‘DJ’ I mean ‘arrange and blend tracks in Ableton Live’ — which isn’t proper DJing, according to many. That controversy aside, that is the easiest way for me to work; by not having to worry about synchronization and beat-matching, one is free to concentrate on the arguably more important parts of DJing, which is song selection and sequencing.

What started as a simple project to select some tracks to play in DJ sets turned into an obession, and I ended up ‘warping’ the entire corpus of tracks — 175 in total. There are only 173 on Soundcloud because 2 were withdrawn.

To make use of my warping efforts is unfortunately a 2 stage process, the first being to go download the music files. These are available on Google Drive. You’ll need a Google account of some sort to download them, but you can just download the “Selected Soundcloud works 1985-2015” folder. https://drive.google.com/folderview?id=0B80j1_axBSvIRWJJMUNvdldmWFk&usp=sharing.

Then, download this zip: http://www.cornwarning.com/xfer/AphexUnreleasedLiveProject.zip. It’s also available in the Google Drive AFX folder as well, in the “Ableton” folder.

There’s a ‘Readme’ file in the project ZIP file explaining how to use the warped files, but the TL;DR instructions are “Unzip the mp3 files, unzip the Project, load the project in Live, and tell Live where to find the mp3s.” It should be self-evident to anyone who regularly uses Ableton Live.

Some observations after working through all those tracks:

1. Tempos are almost all very consistent, making me think that he used accurate clock sources & DAT recordings from very early on. There are a very few with the telltale ‘cassette stretch’ tempo drift.

2. There are several with ‘Sequencer Stop’ pauses where he stops the master clock device, allows the effects to decay, and then restarts the sequence off beat. This blows Ableton Live’s mind. I’ve fixed these as best I can, basically pinning a warp marker on the last beat and then dragging the point where the sequencer restarts to the next measure start.

3. Only a few had ‘intergral’ BPMs, i.e. 130, 140, etc. Meaning that the tempo clock was only accidentally set to an intergral tempo. Or the sequencer device and Ableton Live don’t agree about intergral tempos.

4. A couple of them were unwarpable, and I gave up on those.

5. This set of songs was a torture test for Ableton Live’s automatic warping, and I wasn’t impressed, even by the new 9.2 beta version which supposedly improved automatic warping. It rarely found the downbeat properly, was confused by beatless intros etc. Even though the tracks have a very steady tempo.

This was an interesting project to undertake, and it allowed me to ‘needle’ drop in every track. There’s a lot of impressive tracks in this collection.
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VOLCA JAMMIN

Sometimes you try something and it’s accidentally kinda compelling. The setup was

  • Volca Beats
  • Volca Keys
  • Jupiter 6
  • Meeblip Anode
  • Eventide UltraVerb on one send
  • Audiodamage Dubstation16 on the second send.

This is straight up tracky. It’s live mixing/tweaking. I actually added effects and the anode while recording. There’s minimal EQ-ing on the Volca Keys and Volca Beats.  I did some limiting and EQ on the mix-down and edited out the 16 or so measures where the anode was doing this unpitched farting noise.

Syncing the Volcas to Ableton Live is kind of wonky. It seems to work marginally better if you set the sync mode to pattern. The only way I found to get it tight was to hit the ‘play’ button a few times quickly. If you just hit play once, it always starts out of sync. Somehow resetting the counter to 1:1:0 a few times while Live is playing gets things lined up properly.

http://www.cornwarning.com/chaircrusher/Chaircrusher-2014-10-07.mp3

[audio:http://www.cornwarning.com/chaircrusher/Chaircrusher-2014-10-07.mp3|titles=2014-10-07|artists=Chaircrusher]

The Hallway Samples as an Ableton Live Pack!

I previously had posted about a couple of sample sets I made by banging on stuff in the basement hallway, (Hallway 1 and Hallway 2) but today I went through the steps to package them as an Ableton Live ALP file.

These are Sampler presets, so I don’t know if you can load them if you don’t have the Sampler License, or rather I don’t know what will happen if you try. But you can always use the original zip files and load the samples wherever you like. Just click through above to the original posts.

Ableton Live Hallway Live Pack

Fun with Max For Live LFOs

[audio:http://www.cornwarning.com/chaircrusher/Chaircrusher-2011-08-14-BeatRepeatLFO.mp3|titles=Beat Repeat/LFO Experiment|artist=Chaircrusher]http://www.cornwarning.com/chaircrusher/Chaircrusher-2011-08-14-BeatRepeatLFO.mp3

It’s hard not to be an electronic musician without developing a fascination with random/stochastic processes as a compositional tool. Particularly because when you pay attention to e.g. a Max Roach Drum Solo he seems to be balancing random choices with intentional ones. While Roach knows what he wants in broad outlines, part of what makes his playing great is that he has learned to simply allow his muscle memory and hind brain take over and introduce surprises. By letting go of a score and conscious control he’s participating in randomness shaped by his will.

Max spent a lifetime developing the skills as a musician to allow this sort of freedom in his playing. This demonstration clip is what happens when you set up many random Max For Live LFOs to modulate many, many different things. At the core, LFOs are modulating the Repeat and Grid parameters of a Beat Repeat effect. Then two more LFOS modulate the effect send levels, going to a reverb and delay. A third LFO is modulating the rate of the LFO modulating the Repeat parameters.

Then more LFOs modulate the regeneration level and ‘echo reverse’ parameters of the delay, and the size and predelay on the reverb.

One drum loop is the sole audio source for this. All this modulation introduces a currently fashionable sort of crackle where changing parameters introduces audio discontinuities.

More Granularity — Christopher Hipgrave’s Ambient Software

Christopher Hipgrave’s Ambient is a piece of software distributed by Audiobulb.

Ambient is based around granular synthesis of any audio file. It’s pitch shifted, delayed and filtered, and there are several controls you can tweak to control the sound, though ‘explore’ probably makes more sense in this context than ‘control.’

But it’s definitely worth 10 Eu especially if you aren’t a musician, but want to play with a cool audio toy — load anything and then fiddle with knobs, or just hit the random button for hours of crazy sounding fun.

It’s not perfect — there isn’t any way to map the knobs to midi, and the design of the user interface encourages exploration over purposeful control. It also has a tendency to turn any input into 100 buskers playing at the same time in the Berlin Hauptbahnhof. But it is a lot of fun — something you could turn a 5 year old loose on and they’d have a blast.

Quarry Process

This is Amibient chewing up a version of Meredith Monk’s Quarry Weave, as arranged by me using ImageLine Harmless as a sound source. It sounds like part of a the soundtrack for a Wim Wenders movie to me:
[audio:http://www.cornwarning.com/chaircrusher/Chaircrusher-QuarryProcess.mp3|titles=Quarry Process|artists=Chaircrusher]http://www.cornwarning.com/chaircrusher/Chaircrusher-QuarryProcess.mp3

Quarry Weave

The source audio fed into Ambient:
[audio:http://www.cornwarning.com/chaircrusher/MeredithMonk-QuarryWeave-ChaircrusherInstrmntl.mp3|titles=Quarry Weave (arr. Chaircrusher)|artists=Meredith Monk]
http://www.cornwarning.com/chaircrusher/MeredithMonk-QuarryWeave-ChaircrusherInstrmntl.mp3

Sample Sounds of the MRI Scanner

Recorded these for a guy here at the University, but there’s nothing proprietary about them, so hey, let’s share?

[audio:http://www.cornwarning.com/xfer/MRI-Sounds/BIDE.mp3|titles=BIDE|artists=MRI Scanner]‘BIDE’
[audio:http://www.cornwarning.com/xfer/MRI-Sounds/DTI.mp3|titles=DTI|artists=MRI Scanner]Diffusion Tensor Imaging
[audio:http://www.cornwarning.com/xfer/MRI-Sounds/FLARE.mp3|titles=FLAIR|artists=MRI Scanner]Fluid Attenuation Inversion Recovery
[audio:http://www.cornwarning.com/xfer/MRI-Sounds/GRADIENT.mp3|titles=GRADIENT|artists=MRI Scanner]Gradient
[audio:http://www.cornwarning.com/xfer/MRI-Sounds/KISS.mp3|titles=KISS|artists=MRI Scanner] K.I.S.S.
[audio:http://www.cornwarning.com/xfer/MRI-Sounds/MP-RAGE.mp3|titles=MP-RAGE|artists=MRI Scanner]R.A.G.E.
[audio:http://www.cornwarning.com/xfer/MRI-Sounds/T1.mp3|titles=T1|artists=MRI Scanner]T1
[audio:http://www.cornwarning.com/xfer/MRI-Sounds/T2.mp3|titles=T2|artists=MRI Scanner] T2

All files here.