Guide to Electronic Music Techniques (Part 3)
Performance Controls: Part 3
At the risk of seeming somewhat obtuse, I'd like to start by considering some performance control techniques that don't rely on any performance controls; figure that one out!
Well, there are ways in which you can control certain parameters purely by the way in which you play the keyboard. The most immediate example of this is the use of the delay vibrato feature, which is fitted to several popular synthesisers. By holding a note, the delay circuitry will eventually start to introduce the LFO modulation in a manner similar to that of a violinist who will often apply a degree of vibrato to a sustained note. By playing the keyboard in a less legato manner (i.e. not holding on to any of the notes) then the vibrato has no time to 'appear'. This is an elementary method of controlling a parameter by means of playing style.
A more advanced method of using your playing style to determine a facet of the sound uses the envelope generator. Figure 1 indicates what is going on. If we have the controls set as shown, it is possible to completely change the envelope of the note depending on how we play it. The attack time is set very short, as is the decay; the sustain level is zero, and the release time is set long. If we release the note during the Decay part of the envelope, the generator assumes the value set by the Release control and thus we have introduced a long release time. So, by playing in a staccato manner, the envelope adopts the long release characteristic, whereas by holding down the note, the envelope is cut off after the decay part. Furthermore, if you can gauge the point of release on the decay slope, you can control the level from which the note will attenuate and hence vary its apparent amplitude. This trick will work for both the VCF and VCA envelopes.
Another way of controlling the amplitude of a note using your playing style utilises a slow attack section. This effect is more straightforward, and essentially sets the maximum amplitude of the note from the point during the attack time you release the key. This can be seen quite clearly in Figure 2. It is possible to make a pseudo-combination of these two different effects, for even greater control/flexibility.
Now, let's get onto improving our pitchbending and modulation technique. Probably the most common problem with using the pitchbender is that players tend to over use it, both in terms of frequency and amount. If you bend every other note, the effect becomes monotonous and looses its impact. Similarly, if you persist in bending notes a fifth (say) the effect becomes dissipated and starts to sound more like portamento. To get the best out of a pitchbender you should remember that it is an expressive device - don't dilute the expression. If you are using the synthesiser in a rock environment, it is a good idea to listen to a few guitar solos in order to get the feel of expression in this kind of music. You will notice that because of the inherent design of the guitar it isn't possible to bend a note very far, and that most guitarists stick to a 'bend' of one or two semi-tones. This is the best type of bend to practise on your synthesiser.
Keyboard players may spend hours each day getting to grips with scales etc. (you mean you don't either?), but very little time is spent improving pitchbend technique. The secret is to be able to bend exactly the amount you want to, and to be able to do it smoothly and confidently. Synthesiser controls obviously vary from machine to machine, so you have to 'know' your instrument. A useful exercise is to play a note C (say) then bend up to C sharp then play a B so your synth should still be sounding a perfect C. Similarly you can play a C, bend up to D, then play a B flat and see if you are back to C. This can be repeated for various keys and intervals until you can be sure that you can bend exactly the right interval. You will 'feel' the bend both by the amount you have to move the controller and by listening to the change in pitch.
There are various other little exercises for improving your competence with any form of pitchbender - I'm sure you can devise your own. Using the modulation wheel/lever/joystick, or whatever is more a matter of when not how. This, I'm afraid is up to you - it cannot really be taught. However, it is a good idea to listen to other instruments and see how they naturally add vibrato or tremolo, and to bear it in mind when simulating them.
I hope that I have brought home the importance of the synthesiser performance controls. A synthesiser without these devices is like a ship without a sail - it'll float, but won't go anywhere. A synthesiser isn't a musical instrument (to my mind) unless there is a method of injecting some kind of emotion into the pieces being played - with these controls, far from the synthesisers being a clinical, mechanical machine, it becomes one of the most expressive and sensitive of all musical instruments.
Feature by Dave Crombie
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