Photone Sound Design Tutorial

Transcription

1 Photone Sound Design Tutorial An Introduction At first glance, Photone s control elements appear dauntingly complex but this impression is deceiving: Anyone who has listened to all the instrument s presets will be wondering how this astonishing sonic bandwidth can be controlled with a single panel view. The tutorial addresses this question. Some presets will be chosen from the sound banks as examples and their technical structure will be described to help illustrate Photone's functionality and its potential for professional sound designers. Basic knowledge in the field of sound synthesis and in using REAKTOR is required. Widescreen Sounds Preset 2 of Photone's first snapshot bank loads the patch Pad: Josef Müller which is characterised by its high intensity and volume without being penetratingly loud. This is achieved by a subtle harmonic layering of the oscillators in two steps. Please load the preset and play some notes to get an idea of the sound. Then set UniSp (within the Global section) to 0 and pull the MIDI modulation wheel to its maximum in order to fade out the oscillators 2, 3 and 4. The sound that can now be heard is the preset's foundation, a filtered saw waveform with additional vibrato, chorus and delay. The respective parameters within the Filter and Effect sections will not be described in detail here as, in this case, the detuning of the oscillators 2, 3 and 4 is much more interesting. While oscillator 2 is shifted by a third relative to oscillator 1 and the general MIDI pitch, oscillator 3 is set to a fifth above the main pitch, oscillator 4 a fourth below. When fading in those three oscillators (by pulling back the modulation wheel to its normal position) they blend with the first oscillator to form a minor chord. As the oscillators 3 and 4 are also detuned by 2 and 3 cents respectively, the sound is enriched by additional tremulants. Due to this oscillator layering, a complex harmonic and vivid structure is generated when a single note on the keyboard is pressed.

2 In a second step the UniSp control, initially set 0, now multiplies this structure and spreads it over the complete frequency range. As can be seen in the illustration, the patch is polyphonic but all six voices of the instrument are used unisono, meaning that they are all triggered simultaneously by a single MIDI message and share the same pitch. The UniSp control defines by how many semitones the voices are offset to one another: Set to 0 all play the same tone; when it is reset to its original value of 12 the first voice will play one octave below the normal MIDI pitch (as the Tune parameter is also set to -12, transposing the complete instrument down by one octave), the second plays at the normal MIDI pitch according to the spread interval of 12 semitones, the third voice plays another octave higher etc. much like in large orchestra. Or even better, like using additional registers on a mechanical organ the basic minor chord of the four oscillators is spread over six octaves. In combination with the chorus and delay effects the wide cinemascope sound, mentioned at the beginning of this patch's description, is achieved. This technique is widely used: Refer to the presets 3, 24, 30, 43 or 49 and many others for further examples. Digital Retro Preset 16 loads a typical E-Piano patch that displays the characteristic distortion at high velocities. Two special features of Photone are particularly well illustrated with this preset: first, oscillator slot 4 s numerous special waveforms and their respective special parameters and, second, the possibility to extract several sound control values from one MIDI message. As can be seen in the picture, oscillator 4 not only offers the normal waveforms available in all oscillator slots but also lists many additional types. For example, selecting DIGI activates a whole set of sampled waveforms which can be selected using the symmetry slider. 7Saw, on the other hand, activates seven parallel saw-tooth oscillators that, in reference to one another, can be detuned slightly (by using the symmetry control) to produce chorus like sounds. And finally, 6Sine Additive enables six parallel sine

3 oscillators, whose harmonic structure is adjusted using the symmetry slider, to generate organ-like sounds. As demonstrated, the symmetry as well as the FM control are not applied in the usual manner, instead they are specifically used to exploit the possibilities offered by the special oscillator. Details can be found in the manual. This example uses the Wurli mode to simulate the characteristic distortion of a Wurlitzer E-Piano at high velocities. The symmetry slider adjusts the amount of distortion. As the control is modulated by the envelope E1, whose behaviour is highly influenced by a note's velocity, the distortion effect only occurs above a certain MIDI-velocity threshold. It should be pointed out that the interaction between oscillators 1 and 2 provides another important part of the traditional E-Piano sound. Using frequency modulation, the amount of which is again dependent on the MIDI velocity, they generate its characteristic bell sound. However, we will concentrate on the envelopes and the modulation of their parameters. Envelope 3 is, above all, responsible for modulation of the main volume. (Note its effect as a modulation source in the master section.) As illustrated in the diagram, the values defining the envelope's shape are not static, instead its output values are constantly being modulated: on the one hand through MIDI velocity (controlled by the upper slider row) and on the other by MIDI pitch (controlled by the lower slider row). The faders above the gate knob regulate the envelope's amplitude, those above the attack and decay knobs determine the duration of the respective parts of the envelope. Using the decay fader as an example, the basic mechanism is easily explained: If the slider is set a little to the right and a note is struck with high velocity, the decay time increases slightly. If the lower slider is moved a little to the left the decay time will also increase slightly if a low note is played. Although not intentionally generated in this preset s original role model, but rather incidental to the mechanics of the e-piano, these nuances in combination with the other features generate the characteristic sound. Naturally, this method is not exclusive to simulating older instruments. Nearly all the patches within the snapshot banks are sensitive to the velocity of a note, e. g. to modulate the filter's cut-off frequency. The possibilities are vast. Original and Clone Whilst the previous part of this tutorial concerned itself with the simulation of a familiar type of sound, the following part takes this a step further: the emulation of a guitar. It is generally accepted that realistically simulating the sound of a guitar's strings using subtractive or additive synthesis (even with the help of FM) is extremely difficult. Which is why usually the sound generator and not the sound itself is simulated. A comb filter is normally used as it repeats incoming impulses with high frequencies and dampens them only very slowly very similar to a guitar string whose oscillation, after a short initial

4 impulse, decays slowly. Before dealing with the comb filter in detail, it is necessary to simulate how the string is plucked. Load preset 11 and look at the Oscillator section. All four slots are active, as can be seen at the input of multi-filter 1. Oscillator 4 once again uses a special mode: The click setting triggers a very short sample that perfectly simulates the plucking of a guitar string. The oscillators 1 and 3 produce white noise that, like the sine wave of oscillator 2, after the attack is rapidly muted by modulating their volume with envelope E3. This short period of noise, combined with the initial pluck sample of oscillator 4, provides the necessary first impulse required by the comb filter to simulate the oscillating string. This comb filter is controlled by three knobs that adjust pitch, feedback and damping. Without explaining the technical details it can easily be seen in the illustration that the pitch parameter is set to 0: The virtual string oscillates without pitch shift at exactly the frequency that is determined by the MIDI Note On events. As far as the pitch controller is concerned, the vibrato LFO is an important modulation source. By modulating the frequency with the vibrato LFO this musically important feature can also be applied to the virtual string it would be useless to modulate the white noise's pitch within the oscillator section as White noise does not have a pitch. The frequency of the guitar string is only generated within the comb filter. The knobs for feedback and damping control the decay of the virtual string. The higher the feedback value, the longer the string will oscillate after the initial impulse. The damping controller also comes into play within this mechanism: setting a higher value will result in less damping of higher frequencies within the comb filter s feedback loop.

5 Lowering this value results in a duller sound, equivalent to someone placing their finger on the string and preventing it from vibrating freely. Obviously, the sound of this patch is not identical with that of a real guitar, but it is a decent approximation, that serves as a useful starting point for further sound design. Preset 101 in the 2 nd snapshot bank ( yes, metal can sing ) hints at other possibilities that the comb filter has to offer besides physical modelling. Note that the Resochord FX unit activated in this patch is itself largely based on six parallel comb filters. A Synthesizer Is A Synthesizer Is A... Despite all these possibilities to use Photone as a hybrid work-station and simulate completely different sounds, it should not be forgotten that a synthesizer should nevertheless sound like a synthesizer. While the widescreen sound studied in the first part of this tutorial is a good example of a dense, atmospheric pad sound; in this final part of the tutorial another decisive strength of Photone must be emphasised: its ability to generate classical as well as innovative lead and bass sounds. Preset 119 of the first snapshot bank serves as a good example of a bass patch. Anyone who thinks that this unusually dry, punchy and yet very subtle sound cannot have caused the sound designers too much work should take a look at its programming intricacies, for example the multiple frequency modulation of the oscillators or the slight but crucial modulations of the envelope parameters. However, another in no way less complicated sound is to be discussed here, with which possibly one of the most important areas of creative sound design is touched upon: the Filter section. Please load preset 5 of the first snapshot bank. If the sonic world of Jeff Mills was the inspiration for the widescreen sound, here it is doubtlessly the sound of Ed Rush & Optical or Bad Company.

6 As can be seen in the illustration of the filter routing section, both multi-filters are being used in series. The signals of all four oscillators are fed into filter 1 whose output is used as the input for filter 2. In addition to this, the filter bypass slot feeds the signal of the oscillators 1 and 2 around the filters, but their amplitude is modulated by the E1 envelope as can be seen in the bypass amp menu. The filter signal s amplitude modulation is hard-wired and cannot be influenced, however the point at which it joins the signal flow can be: pre or post filter routing. As can be seen in the filter amp menu, in this instance it is post. Focusing now on the filter itself, the modulation of the filter's cut-off frequency is of most interest. As in the e-piano example, an envelope (E2 in this instance) and the MIDI velocity are used as modulation sources but, in addition to this, the MIDI modulation wheel is integrated to provide additional control of the sound's overtone spectrum. As a final modulation source, the tracking module is activated by depressing the SCL button. Depending on the MIDI note pressed the cut-off of the filter is altered. As opposed to the helpful, but conventional key tracking used for the Envelope section in the E-Piano example, in this instance the four control elements offer a more individual manipulation. An advanced algorithm is used to control this very important part of sound design. The pitch range is split into four areas, and a separate key tracking mechanism is assigned to each of them. The slider on the far left is responsible for the lowest notes, in this case lowering the cut-off by the largest amount, producing a dull, growling sound in the low registers. For slightly higher notes, controlled by the fader 2 nd from the left, the cut-off reduction is a little less. The fader on the far right takes care of the highest notes; here the cut-off is in fact slightly increased, resulting in bright and shiny sounds in the high registers. Tones in the mid-range are managed by the fader 2 nd from the right, and are dampened by almost as much as the lowest notes; applying a special, individual touch to this sound and its behaviour when played with the keyboard. Finally, the large number of different filter types, whose possibilities we cannot even begin to describe here, should be noted. Besides the band-reject filter used in this example there are low-pass, band-pass and high-pass filters, comb filters, phaser, peak and notch filters. In particular the low-pass filters exceed the capacities of other instruments. Beside the clean variants there are also modes that do not stop at the mathematical sterility of digital filters but add technical innovation to bring the sound to life. This very brief description for a very complex component of Photone deservedly finds its place right at the end of the tutorial. Nowhere near all of Photone s potential has been explained or even mentioned. But hopefully your curiosity has been aroused. Innovative sound designers and well-known musicians have delved into the possibilities of this instrument and created a wealth of different sounds, all of which are saved in the snapshot banks. And so, as this tutorial has done with just a few of the sounds, all the other high-quality patches are waiting to be analysed and understood.