Rather bright or dark? Here is a question that is asked when you try mouthpieces in a music store or when you create yours with Syos. But what does that exaclty means? Maxime, our psychoacoustics expert, is going to give you some explanations.
What makes it bright ?
What really differenciates the sound of a sax player from the sound of another sax player? What words can we use to describe those differencies? This was our biggest question when we created Syos. We did long researches on the internet, we asked on the saxophone forums, we did surveys on Facebook, but we also had deep talks with a lot of sax players as well as hundreds of sax mouthpieces tests.
A dimension came always in the first place: the brightness of the sound.
Brightness is the first criteria that allows to say that two sounds with same height, same length and same volume are sounding alike or not. Two sounds which have the same brightness will be much closer from each other than two sounds which have very different brightnesses.
How to define brightness?
The point here is delicate: how to define a sensation? If I asked you "How would you define brightness?" I bet it would be hard for you to answer with a simple and precise sentence. But no worries! During my PhD studies at the IRCAM, it is precisely what I've been working on.
My answer here is that this is not an easy task to describe a hearing sensation. It is like, for example, to define what is red: the simplest answer would be to give a definition with an example, giving examples of objects that would be red and examples that would be another color. This definition depends from our senses and then from our perception of colors. We call it perceptual definition . However, there might be among you, readers, a scientist who will object that we can also give a physical definition, precising the wave lenght associated to the color.
For brightness, this is exactly the same: sax players would be able to tell David Sanborn has a very bright sound, meanwhile acousticians would talk about sound spectrum and high frequencies.
Then, which definition should we choose?
The two types of definition are valid but they do not say the same thing. From one side, the perceptual definition matches much more with reality as it direclty comes from the person who is hearing the sound. Nevertheless, it is a very subjective definition: a person could say a sound is bright as another one could say it is not bright at all.
This is the case for ambiguous tones, like John Coltrane's. A study done with more than a hundred sax players shows that 34% of them hear it "Dark" while 66% hear it "Bright" (read the complete study : The mystery of John Coltrane's sound)
|Perceptual definition||Physcial definition|
Closer from reality
Vary according to individuals
Yet the physical definition is unbiased : to any sound, or rahter to any sound signal, one can associate a measured value of the brightness. On the other hand, this value does not have a signification on its own: to be pertinent, it has, somehow, to match with what people perceive.
Brightness perceptual definition
In order to illustrate the variability of perception among people, we did a small experience: we selected recordings of different sax players, and for each of them we chose a 5 to 10 secs extract. We created a quizz where participants were asked to give a note to the extracts on a scale from 1 to 10, about power, brightness and width. We were more interested in brightness. The participants did not know the name of the sax player, they only had the recording to judge. You can find the complete quizz and make the experiment by cliking this link describing the saxophone tone. More than a hundred sax players answered the quizz, let's observe the results:
On this graph, the recordings used for the quizz are classified from the one which got the lowest brightness average note (the winner is Paul Desmond) to the one which got the highest (our champion Michael Brecker). The black line represents the notation average disparity : the biggest it is, the more controversy about the tone. Here, the average disparity stays relatively steady even if Kenny Garrett and Sonny Rollins seem to create a slighlty more important disagreement.
We did here a kind of brightness scale with the sonor extracts, like an oenologist could do it with wines, or like one could do it with perfumes. Other more complex experiments allow to study brightness, for example the Stephen Mc Adams' Timbre Space (which is mentionned in this article: how to describe a sound) . One of his studied dimension is brightness.
Physical definition of brightness
Several acoustics and psychoacoustics studies (if you don't know what those words mean, you should definitley read this article : Warm, bright, focused, dark? Psychoacoustics brings some light!) have been done about the physical characterization of brightness which has been then generally associated with "the quantity of high frequencies we hear in a tone".
There is even a psychoacoustic indicator, the acuity, which represents the sounds brightness. One way to calculate it consist in watching the spectrum's gravity center . It is the balance between the quantity of low and high frequencies in the sound. This measure is mostly used for industrial applications, and one should verify how to use it in order to describe the brightness of the saxophone tone.
How the saxophone mouthpiece can change the brightness?
The mouthpiece is the interface between the musician and the instrument, yet it is an essential piece in the creation of the sound. Let's keep in mind, the musician first produces the sound with his will, technique, embouchure (by the way, for the sax players, here are 3 exercices to practice your own sound: long tones, overtones and 5ths/8ves), but the mouthpiece's geometry will boost certain characteristics more than others. Thus on some mouthpieces it will be easier to get bright sounds than on some others. The baffle and the chamber are two parametres especially important to play with the brightness of a mouthpiece.
To be read :