Numerology Techniques #2 : Ambient Counterpoint

This episode explores a Numerology technique involving the use of two similar patterns whose lengths vary relative to each other in a non-traditional manner, such as a pattern of five beats vs. another in seven beats. In the context of rhythmic composition, this is usually called polyrhythm, but here we will explore it in an ambient context.

This compositional strategy is something that is quite easy to setup in Numerology, but can be a very time-consuming manual process in other programs -- especially if you want to fully pursue the creative options offered by this approach, such as changing the length of a pattern within a composition. Two other musical concepts explored here are counterpoint, as we will be building a composition of two complementary voices, and to some extent canon, as we will incorporate delayed versions of our primary melodies.

This video also demonstrates how to build compositions in Numerology with multiple parts, including the use of "auxiliary stacks", which are very useful for effects processing.

Our musical inspiration this time around is Brian Eno's Discreet Music. The first purely ambient work that Eno released, it is a composition of about 30 minutes, "recorded [and performed, by Eno himself] at Brian Eno's studio 9.5.75", taking up an entire side of the album. In his book Brian Eno : His Music and the Vertical Color of Sound, Eric Tamm (with quotes from the liner notes to Discreet Music) describes the piece as

composed of "two simple and mutually compatible melodic lines of different duration stored on a [synthesizer with a] digital recall system." One melody consists of the pitches c" d" (rest) e' (rest) g'; the other is somewhat more elaborate: d' e' (rest) d' b g (rest) d (rest) e" g" a" g" (The designation of the octave positions in these examples follows the scheme employed by the New Harvard Dictionary of Music; see its article on "Pitch").

Having composed the melodies and set up a tape-delay and storage system, Eno's activity as a composer/performer was limited to setting the tunes in motion at various points, and to "occasionally altering the timbre of the synthesizer's output by means of a graphic equalizer." The musical result was half an hour of simple, tranquil, repeating and overlapping melodic segments -- a kind of switched-on, slow motion heterophony.

Here is a diagram of the signal flow Eno used for the composition:

This episode's video demonstrates how to build a very similar system in Numerology, using a pair of sequencers that repeat at different lengths. Instead of a single synthesizer, the example uses two, allowing you to adjust synthesizer sounds and delay settings individually. As a replacement for Eno's classic tape delay system, the excellent Augustus Loop plugin from ExpertSleepers is employed.

Something not demonstrated in the video, which you are encourage to pursue in the privacy of your own studio, is the addition of graphic equalizers or other filtering options to the signal chain. Apple's built-in AUGraphicEQ is quite handy for this purpose. I find the 10-band setting to be the most useful for this situation.

There are a number of ways that you can extend this technique: You can construct different presets that vary both the pitch content and the length of the patterns. Or experiment with the processing options available in the various audio effects to modify the sound. You can assign MIDI hardware controllers to enable you to control the system directly (control-click on a parameter in Numerology, choose "MIDI learn", then move the desired MIDI controller), or use Parameter Modulation to add automation to various parameters.

There are two examples. The first is the same one created in the video. You will need Free Alpha and Augustus Loop installed to run it properly. The second example uses Apple's DLS synth and built-in effects, so it can run without anything extra installed.