We’ve seen in the previous chapter how to create a synth of a particular color.
How about taste and smell?
This part is less precise compared to color, as it relies on a single basic feature of the soundwave whence these synesthetic features originate: the wave phase. In short, a positive phase corresponds to a sweet/acid/fresh taste and to a sweet/spicy/flowery smell, a negative phase corresponds to a salty/sour/bitter taste and a fresh smell. In the picture below, you can see an example of positive phase (the blue wave) and negative phase (the red wave).
Live acoustic sounds have a positive phase, so they taste sweet and smell spicy/flowery. Sound recording through a microphone inverts the wave, just like a simple camera lens inverts the image when we take a photograph.
So, in order to invert the phase of a live acoustic sound all we need to do is record it. If we need, say, a sweet taste for a recorded acoustic sound we can invert again polarity once recorded. This is especially useful for vocals, as a recorded sound will create a mental image of what’s performed, and an upside-down vocal track will create the mental image of a person singing upside down, which is obviously not desirable when it comes to transferring a pleasing or consistent image to the brain. Keep in mind certain systems, such as most standard soundcards working on recent versions of Microsoft Windows, invert again the recording, so you get a straight recording the first time. Most Android smartphones will record an inverted sound. In order to verify whether your recording system inverts polarity, you can play a test wave with a very recognizable phase, such as a loud square synth at a low frequency, and analyze the recording to determine whether the phase corresponds to the original electronic phase.
For instance, if you create a sound selecting a square wave on the first oscillator and turning down to zero the volume on the other two (see picture above), play a long C3 note and save a sound file, you will come up with a sound wave looking like the one in the picture below.
If you play this sound and record it again with a microphone placed in front of the speaker, you should be able to tell, analyzing the resulting waveform in the Edison sound editing tool that comes with FL Studio, whether the phase looks like the original electronic sound or it got rather inverted by the recording device.
Pure electronic sounds, such as the sound of an oscillator, have a negative phase, so they taste salty and smell fresh. In order to make them taste sweet, we must invert polarity.
The quality of the sweet taste, whether cherry-sweet or custard-sweet or chocolate-sweet depends on several sound features, such as color, texture, pitch, depending on kind and quality of the sound and on sound dynamics. I.e., a certain kind of compression, such as a maximization preset combined with a mid-low knee, will create a “glossy”, “smooth” and semi-compressible surface resembling that of certain fruits. Giving the synth a purple color could, for instance, convey the idea of a fresh plum. Smell is mostly localized in the low frequencies, below 250Hz, taste is localized in the mid-high frequencies. So if you want a sweet taste and a fresh smell for an electronic kick, you must invert the frequencies above 250Hz. But it depends a lot on all the other factors affecting the sound. Once again, this is not a precision science, and this is the part where artistry kicks in to replace pure theory and strictly technical considerations.