Subtractor Basics by Strobe, 12 April 2003,
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About the Subtractor Synthesizer
As you might know, the Subtractor is a member of the analog(type) polyphonic synths, using subtractive synthesis. Some details, if you don't mind:
Basically, subtractive synthesis goes through a certain circulation within the different modulation- parameters.
First, the Oscillators (VCO) create certain basic waves using subwaveforms which are layered over each other. Thus, you alter the basic character of your sound by switching through the different waveforms, provided in Subtractor (please refer to the manual for further description of each of those). But you will for sure know the basic types of waves, as there are sine, sawtooth, square, pulse and triangle.
Second, the freshly generated wave wanders into the filter- section (VCF), where according to the chosen values certain frequencies of the wave are damped/cut off by limiting oscillation.
This also provides for the basic shape of your sound-baby ;).
The third step is to amplify the resulting wave oscillations as done in the VCA (or the Amp section of Subtractor). As the simple use of an amp would result in some loss of time-dynamic, we can be grateful to use envelope curves.
As you can see in the picture, there are four parts responsible when triggering a sound: Attack, Decay, Sustain, and Release. They all are sequentially setting in, a key is pressed.
Attack controls how fast a signal goes from zero to maximum level.
Decay determines the amount of time it takes for a signal to reach the Sustain level.
Sustain is important for the level which is held until a note ends (key is hold)
Release, finally, is responsible for what happens after a note ends: how fast the envelope fades to zero, to be precise, how long a note keeps on sounding after the key was released.
So far, speaking about technical aspects of shaping the body of your sound. As next approach you can modulate this body, to get it rougher or clearer or whatever. Speaking of part four ,(see pic 1 for details) there you can control how the filter build up and last, using the filter envelope; same thing with the modulation envelope. each of the according ADSR regulates in what way the specific destinations are triggered.
Finally, there is the LFO section (five), as described here. The waveforms gene-rated by LFOs are not to be heard but to modulate the sound sent off by the Oscillators. Doing so, the use low frequences to oscillate - therefore the name. At Subtractor's LFO1 you can choose the lowfreq's shape to be generated and in LFO2 kinda independend forms are produced. By editing the rate- and amount value, you can create tones slowly swinging up and down, or by increasing these two values get some rough and distorted sounds, depending on your filter-settings.
[for futher technical details please check the reason-manual]
What the Subtractor is 'good' in
I tend to use the subtractor as source for 'normal sounds', as there are basses, string- or bell-like melodic elements. The Malstroem is my first choice when FX are concerned. That's how i view it, and keep it while doing tracks.
The Subtractor provides such filigranous settings which, if set properly (needs a lot of patience imo), create great sweeps, as well as pounding basslines, whereas i worship the Malstroem for being so suitable in doing alienated effect- work in a fair amount of time (due to its power, the combined granular-and wavetable-synthesises). But I guess anybody has to find his/her favourite for certain tasks.
(My) System of sound-shaping with Subtractor
Well, basically your route of changing all the nice little knobs and buttons in Subtractor should not differ too greatly from the sequence described and illustrated above (pic 1). I will try to describe my aproach on Subtractor to you:
I start off, choosing a suitable waveform of the provided spectrum, depending on what kind of sound i want to create. Switching on the second OSC, prepared with a waveform suiting, and more emphasising the first, let the sound build up more intense/voluminous, especially if the two OSCs play at different octaves.
If i want to 'rough-up' the resulting soundstructure i change the phase-off of each of the OSCs as well as increasing modulation of OSC1's frequency by OSC2. This often let the tone loose cleaness if this was intended. Afterwards I continue with cutting the signal's body by using the frequency-filter.
I keep freq- and res-levels quite low, if aiming for damp/smoother sounds, increasing freq if wanting to sharpen them. You might try to use resonance to produce more acid-like types, for it controls freq's characteristic or range, as well as its quality.
Then it is time to limit the body of our baby: use tha attack-value to determine how smooth the sound starts playing. For the beginning it is enough to change the release-level to get some noticeable difference. Increase it to get longer sounds and strings.
To use the filter as well to alter the tone's build-up, I edit the filter-envelope, resulting in a damp start and a sharp ending, for example. Now the point for me has come to decide about the amount of random or rhytmical movement within my signal. this i do by changing LFO1 and LFO2.
A cool way is to combine alterations starting immediately (LFO1) joined by some vibration or such coming up slightly delayed in LFO2. The choice is, of course, yours.
Bear in mind that with Reason 2.0 it is possible to synchronize the first low frequency oscillator along with the track's bpm. This is a slight roug-draft how one could approach in 'designing' sounds.
Worxample - Creating a smooth bass
For our little example, i've chosen waveform 10, playing the 2nd octave on the first OSC and as support nr. 9 on OSC2 (also at 2nd octave). Leaving LoPass12, for the Filter-Freq I set 30, the Resonance at 18 (leaving away Filter 2 this time).
To shape its body thoroughly I increase the Amp's Attack value to 44, both Decay and Sustain to maximum level and Release at about 61. what we should have got up to now is a nice, smooth bass, no? as simple as that ;) no we want to make it a bit more interesting...
First we build in a slight but noticeable 'slip' within our bass-tone by sliding the Filter-Envelope Attack-controller to 63 and lowering the Decay-value to 30, leaving the Amount unchanged. You'll hear the difference, just turn up the volume.
Then we go on and ad some 'vibration': switch to Amp within the LFO2 section, turning the Rate- and Amount-value about half way up (64 or so). See? Or gentle efforts resulted in some sound which would suit some downbeat-track, or such. By further working over some more of the parameters you quickly can supply this first try with dirtier characteristics, and then of course just ad some effect- devices like Reverb to enhance its distinctiveness.
So far, so good - thank you for paying attention ;) i hope this short summary of facts about this powerful device provided by Propellerhead's Reason is somewhat usale to you. If so, be sure to let me know for I'd like to just go ahead with some Malstroem stuff.
[please excuse grammatical or spelling mistakes, you might come across. I'm not a native english speaker/writer.]
reasonally yours ;D strobe