Revenge of the Combinator
Pages: 1, 2, 3, 4

Example 1: Wave Sequencing

The SubTractor oscillators’ waveform parameter is available as a CV destination in the Combinator programmer. (The Mälstrom oscillator wavetables, which have to be loaded from disk before they can be used, are not.) The curve CV output on a Matrix, which changes in stepwise fashion from note to note, is a good source for a CV to switch among the SubTractor’s waves.

In the Combinator patch waveseq.cmb (download link below), three Matrix sequencers are used at once. All three send their curve outputs to the Combinator’s rotary CV inputs. The first Matrix is also playing the notes you’ll hear when you click on the sequencer’s start button. (I suggest setting the tempo to about 108 bpm.) The third Matrix controls the SubTractor’s amp envelope attack time, and also the filter envelope’s decay time. The amount of modulation is inverted for the decay time.

A second SubTractor is used strictly as an LFO, modulating oscillator phase on the main SubTractor--again, not a modulation that could be accomplished without routing through a Combinator’s rotary CV input, as there’s no CV input for phase on the SubTractor’s own rear panel. The phase modulation makes the tone a little more interesting. This LFO is also used to control the aux send level on channel 1 of the line mixer. The aux send feeds the two DDL-1 delays.

A fourth Matrix pans the output of the SubTractor. One result of the panning, because the line mixer’s aux send is stereo, is to send some of the notes to the left-side DDL and other notes to the right-side DDL.

The Matrix sequences are different lengths, ensuring that repetitions of the note pattern are articulated with different waveforms and different envelope characteristics. Here’s what the setup looks like:

Wave Sequencing Modulation Routing Wave Sequencing Combinator. Click to magnify the modulation routing screen.

I also added a chorused bass part beneath the Combinator riff to produce a texture vaguely reminiscent of Tangerine Dream:

Example 2: Vocoder Modulation

The vocoder modulation Combi called vocodermod.cmb (download link below) uses two of the band outputs of a vocoder as CV modulation sources. These are routed to the first two rotary inputs of the Combinator, where they control the index parameters of the oscillators in a Mälstrom. A simple Redrum pattern is used as a rhythmic input to the vocoder. To hear the result, start the sequencer and then play notes (preferably one sustained note at a time, in the low range of the keyboard). The CV signals create a more complex rhythm-based index modulation than could be accomplished with the Mälstrom’s Mod generators alone.

Vocoder

Triggering the vocoder with a Redrum pattern.

I chose the two sounds in the Redrum because they are clearly different in frequency. To hear the raw drum pattern, unmute channel 2 in the line mixer. You’ll note that the rhythm is backwards with respect to normal pop music: The snare is on 1 and 3.

Rotary 4 of the Combinator is used to invert the CV output of the Mälstrom’s Mod B. That enables Mod B to modulate the cutoff frequencies of the two filters in opposite directions at the same time, which is not something the Mälstrom can do by itself. (Only one of the filter knobs will appear to be moving, because the other modulation is done internally within the Mälstrom.)

In the musical example, the Combinator patch plays the primary rhythm part, backed up by a throbbing bass coming from a SubTractor and a breathy lead played on another Mälstrom through an RV7000 reverb:

Example 3: Lead Synth

The lead synth Combi called leadsyn.cmb (download link below) is loosely based on the default SubTractor patch. It uses the SubTractor’s own modulation envelope output for several things. First, the envelope controls the SubTractor’s own LFO 2 amount and rate. Rate can be controlled directly within the SubTractor, but as the mod envelope can be given only one output at a time from the front panel, controlling amount and rate at the same time is not possible without the aid of the Combinator. In this case the mod envelope’s direct output is controlling oscillator phase. The mod envelope also controls filter resonance, so that as the note decays the resonance increases.

Next, the mod envelope lowers the Damage parameter of the Scream distortion effect, so that sustaining notes acquire more damage as the envelope decays. At the same time, the mod envelope ducks the output of the Scream, so the damage doesn’t become overwhelming. The SubTractor LFO 1, meanwhile, is moving two stages of the Scream’s EQ in opposite directions to create a subtle timbre shift. The result is that each note you play on the keyboard starts with a great deal of presence and then decays into a swirling, distorted wash.

Screaming Mod Modulating the Damage and EQ in Scream.

In the music example that uses this patch, you’ll need to listen closely to hear the swirling echoes after the lead notes, both because the aggressive drumming covers up some of the sound and because this type of background sound is not well preserved during the data compression process that creates an MP3 file:

Because of this, I also recorded a file in which the lead synth line is soloed:

The pitch-bends and modulation wheel moves (the latter opens the filter in the SubTractor patch) were recorded from the keyboard, not automated. The drums are a stock Dr.REX pattern being mangled by a Scream.

From Many, One

The Combinator encourages Reason users to think of their complex patches as single entities rather than as jumbles of disparate modules. Ultimately this doesn’t just improve the workflow; it can help you to think about your music in more coherent ways. But don’t forget: You can still automate the controls of individual modules within a Combi by assigning them to sequencer tracks in the normal way. You can also patch CV signals directly into a module within a Combi from a module outside the Combi, bypassing the Combinator’s rotary inputs. I don’t recommend the latter, as it will prevent the Combi from working as expected the next time it’s loaded. But Reason doesn’t enforce a rigid way of working. The choices are up to you.

Music Examples: Get Your Combo Workin’

Here in one place are the previous MP3 examples of the Combinator in action. If you have Reason 3.0, you can also download and try the Combi patches and Reason songs (388KB Zip file) I used to make them.

Jim Aikin writes about music technology for a variety of publications and websites. His most recent books are Power Tools for Synthesizer Programming and Chords & Harmony.

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