When one says “xyz” harmonica has a bright tone and that one has a darker tone what do we mean?
Is one tuned a slightly greater number of hertz over the normal and the other a few hertz lower?
That is a very good question! In fact, among those who have not studied this, there is much speculation about what exactly is the meaning of the terms “brighter” and “darker” (sometimes also called “warmer”) tone. One thing is certain: it has nothing to do with the basic tuning frequency of a reed (which would result in differences of pitch, e.g. higher or lower pitch).
When the harmonica is played, the sound that is produced is not the actual vibration of the reed itself! It is the vibration of the column of air that the moving reed produces. This column of air is actually quite complex, consisting of the shape of the channel in the comb that the reed occupies, as well as the shape of the player’s mouth, throat and even the length and diameter of their trachea, and finally the cupping or position of the player’s hands around the harmonica. These result in the vibration’s frequency being composed of many different frequncies above and below that of the “main” frequency that we hear and identify as a C or D or whatever.
Contrary to popular belief, the comb’s material (wood, plastic, metal or composites of one sort or another) does not influence the tone that a neutral or blind listener (meaning: a listener who does not know anything about the composition of the comb or the make of the harmonica) will hear. Some rather elaborate experiments have shown this to be the case.
So the terms “brighter” or “darker” or “warmer” actually are subjective feelings that the listener reports when hearing the complex air column vibrations and its composition of lots of frequencies above and below the “main” frequency. When the lower frequencies are more dominant compared to the higher ones, most people tend to say that the tone is “darker” or “warmer” than when the higher frequencies are more dominant than the lower ones (“brighter” sound).
So … sorry that you asked? I hope not!
Thanks for that explanation!
I would have thought it to be the other way around…I would have thought that “warm” meant the the lower frequencies were dominant and that the “bright” tone would have have more dominant higher frequencies…
Are you sure you didn’t turn those two definitions around by accident?
Of course that’s just me… I’ve been wrong so many times that I’m getting used to it……
Thanks man, that helps a lot…still a lot to think about, but clearer.
From Ayr Scotland
Thanks @blues_harp_cat !! I did indeed accidentally turn them around !! I’ve corrected the text so that it is now correct !
Whew NOW it does make sense. Thanks guys
I did some more reading and see that timbre may be the term I’m looking for. It seems to be more concise to the question that I originally posed…?
Yes, @expat48 , timbre is indeed the term – but I wanted to keep my reply as simple as possible
Before I retired much of my research concerned the perception of complex acoustic signals (including spoken words) and how they are represented in the central nervous system. I had several physicists who were working in my lab and they were specialists in the physics of sound. They were always throwing around terms that I had perhaps heard – but I really did not know their exact meaning; and timbre was one of them!
I know my father’s expression. He played, among other things, Saxophone and the various types such as alto, tenor, soprano and baritone saxophones the term was used.
Regards from Astrid
Before I retired I was in the medical field, but now I’m able to delve into anything that appeals…astronomy, rockets, music etc etc.
Thanks for all your feedback man.
On my guitar is a tone knob. On 10( fully open) it’s bright. In 0n 10 it’s much less bright. It’s the same note. I’d be interested to see the pattern on an oscilloscope. Someone said on the harmonica it has different frequencies but that can’t be it because it would be a different note. I suspect that the sound of a note is very complex and not a simple sine curve. Different tines gave the same general shape and vibrations per second but have many different peaks and valleys within that curve.
Your first sentence (quoted above) is wrong. On different instruments you get different combinations of harmonics with different amplitudes, although each type of instrument is playing the same note. The result is a very complex wave from each instrument.
In your second sentence (quoted above) you correctly recognize this complexity. It is this resulting complex waveform that makes it possible for us to recognize the sound as coming from, for example, a trumpet or a saxophone or a harmonica even when we cannot see which instrument is being played.
Studying the physics of sound will help you understand this.
Nice discussion in this thread, really enjoying it and a lot to think about. Thanks guys.
I can see there is a serious link here between physics and human biology. Aren’t we amazing creatures.
Slim you are truly a no nonsense deep thinker.
My understanding is the comb material effects overall pitch. Aside from certain keys starting higher. F, E, D, C, B, A, G are high to low. I do have a low E and a low F. Eb older is higher pitch in that mix. But when I looked into having a custom made one, cherry had a darker tone than maple, and new ones some have bamboo and the resin ones, got a couple east stop, they seem bright.
But over all I think you can just control that with experience. Though I did collect some cherry wood and plan on making a comb for this opera old timey harmonica. I kept the plates.
As I stated above, comb material does not influence pitch (the identifiable note), but the comb itself (even microdifferences in reed chamber length, width & shape) does influence the complex combination of frequencies (harmonics) that is generated. This, in turn, is perceived by the listener as the same tone (note/pitch) but having a different “tone color” (resulting in descriptions such as sounding “lighter” or “darker”, etc).
Cherry is warmer, Maple is hardwood, bright and clear and Birch is also a bright wood, bamboo seems to be also. However I will make a cherry one and find out. Cherry is softer, but the bush cherry I have is very hard.
The reed length and material decides pitch and note, the chamber size also. My daughter played clarinet back in the 80’s, the first a cheap resin one, then I met a guy with a wooden clarinet. They played the same, but one was harsh one was mellow,
The only “honest” way to settle the question about the tonal influence of comb material is to perform a “double blind” test, ideally also using a machine to blow and draw the notes in order to eliminate all possible differences in playing technique (tongue position, throat muscle involvement, air flow speed and pressure, hand cupping, etc.).
Of course there are other components that also must be kept identical: the reeds and reed plates, the cover plates and the exact same dimensions of the different combs (chamber width, length, 3-D shape,etc).
Any other sort of test will most likely result in you hearing exactly that which you “expect” to hear (test bias).
Meh, I’ve been playing over 60 years, perhaps my ears are better or worse than yours, also I know tonewoods, like an sg of mahogany is darker than say red alder, also les paul has maple top and mahogany base to maintain brightness. Woods affecting tone has been known for centuries. now the harp is a tiny little comb, so the influence may be negligible, but I don’t really care.
So, I could care less, how blind everyone is. But when I make my cherry comb, I’ll drop a line on here.