saxophone harmonics
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likesomepassingafternoon@gmail.com - 30 Nov 2008 05:45 GMT When all the keys are closed on a saxophone, the fundamental produces the natural harmonic series. As keys open up, and the fundamental raises in pitch, the overtones get progressively sharper. Why is this? How does this affect our perception of the tone? Thanks for your help.
D.B.
Jens Rodrigo - 30 Nov 2008 23:09 GMT > When all the keys are closed on a saxophone, the fundamental produces > the natural harmonic series. As keys open up, and the fundamental > raises in pitch, the overtones get progressively sharper. Why is this? > How does this affect our perception of the tone? Thanks for your help. Perhaps this can help:
Saxophone Harmonics: http://www.petethomas.co.uk/saxophone-harmonics.html
Saxophone Harmonics: Hearing with the Ears and the Embouchure: http://www.wku.edu/~john.cipolla/saxharmonicsWKU.pdf
Saxophone acoustics: an introduction http://www.phys.unsw.edu.au/jw/saxacoustics.html
JazzLab: Harmonics on tenor sax http://www.youtube.com/watch?v=wAPoAPfsdpc
Saxophone Harmonics http://video.google.com/videoplay?docid=6604414214026077986&hl=en
Cheers Jens
likesomepassingafternoon@gmail.com - 01 Dec 2008 03:42 GMT > likesomepassingaftern...@gmail.com> wrote: > > When all the keys are closed on a saxophone, the fundamental produces > > the natural harmonic series. As keys open up, and the fundamental > > raises in pitch, the overtones get progressively sharper. Why is this? > > How does this affect our perception of the tone? Thanks for your help. Thanks for the links although none of them address my original question. I'll be more specific: I want to know about why some tones have inharmonic partials, including saxophone in some registers, clarinet, and strings under high tension and how this affects our perception of musical tone. Thanks.
D.B.
> Perhaps this can help: > [quoted text clipped - 9 lines] > > Cheers Jens Ethan Winer - 01 Dec 2008 13:38 GMT > I want to know about why some tones have inharmonic partials, including > saxophone in some registers, clarinet, and strings under high tension and > how this affects our perception of musical tone. I know that bells and chimes etc have non-related overtones, but I'll take your word for it that reeds and strings can do that too. With normal tuning, guitar strings have only related overtones, but when the strings are old and stretched, the overtones can be slightly off (a few cents). That is, you pluck a single string and it sounds out of tune even though it's seemingly only one note.
As for pitch perception, I'd think that non-related overtones could possibly make it more difficult to identify the pitch. For example, it can be tricky trying to identify the pitch of bells and chimes because there are multiple string unrelated tones all sounding at once.
--Ethan
Helmut Wabnig - 02 Dec 2008 15:57 GMT >> I want to know about why some tones have inharmonic partials, including >> saxophone in some registers, clarinet, and strings under high tension and [quoted text clipped - 13 lines] > >--Ethan Each string or pipe has inharmonic overtones, not only due to imperfections of the string, but for technical reasons. Example: piano string. Where does it begin and where does it end? How precisely can you define the contact point on the stop? For higher partials the apparent string length is physically shorter than for the fundamental wave. Same applies to pipes and other resonance bodies.
w.
Savant - 03 Dec 2008 13:54 GMT On Nov 30, 9:42 pm, likesomepassingaftern...@gmail.com wrote:
> > > When all the keys are closed on a saxophone, the fundamental produces > > > the natural harmonic series. As keys open up, and the fundamental [quoted text clipped - 24 lines] > > - Show quoted text - I'm not an expert of musical acoustics...but I do have a copy of Olson's "Music, Physics and Engineering." 8-)
According to Olson, the harmonic series for a saxophone is regular. I.e., tones produced at n*f, n being an odd or even integer. A saxophone does appear to be unique in that the amplitude variation of the overtones varies irregularly with the fundamental. However, the overtones are still n*f.
I think what you might be experiencing - and, again, I'm no expert - is the natural sharpness that occurs with overtones relative to equal temperment tuning. Take, for example, the second overtone, which would be 3*f. Musically, this should be an octave and a fifth above the fundamental. However, equal temperment dictates that this musical note should be 2.997*f to be "in tune." Thus, the 3*f overtone that is heard is perceived as being slightly sharp. As n increases, so will the degree to which the overtones sound sharp, with the exception of those that fall on octaves (i.e., 2*f, 4*f, 8*f, etc.).
I believe this relationship would be similar for any musical instrument that produces n*f overtones, whether n is odd, even, or both.
HTH.
Savant
Ethan Winer - 03 Dec 2008 16:30 GMT Savant,
> According to Olson, the harmonic series for a saxophone is regular ... the > overtones are still n*f. Yes, I just did an FFT on a few sax samples, and all the overtones were evenly spaced when viewed on a linear frequency scale. So if there's any deviation in pitch, it's very minor. Or, more likely, as you described related to tempering.
--Ethan
Don Pearce - 03 Dec 2008 17:17 GMT >Savant, > [quoted text clipped - 7 lines] > >--Ethan Download a copy of APTuner.
http://www.aptuner.com/cgi-bin/aptuner/apmain.html
It is intended to be a guitar tuner, but when you enable the graph display you get a moving set of lines of the first five (I think) overtones plus fundamental. It shows how many cents each is out of tune, and how they change as the note decays. Fabulous implementation of an FFT.
d
 Signature Pearce Consulting http://www.pearce.uk.com
Ethan Winer - 04 Dec 2008 14:29 GMT > when you enable the graph display you get a moving set of lines of the > first five (I think) overtones plus fundamental. It shows how many cents > each is out of tune, and how they change as the note decays. Fabulous > implementation of an FFT. Very cool!
--Ethan
Salmon Egg - 03 Dec 2008 18:16 GMT In article <f996950c-5b4e-4ee7-97cb-8cb24b7e5ce3@t3g2000yqa.googlegroups.com>,
> According to Olson, the harmonic series for a saxophone is regular. > I.e., tones produced at n*f, n being an odd or even integer. A > saxophone does appear to be unique in that the amplitude variation of > the overtones varies irregularly with the fundamental. However, the > overtones are still n*f. This is only approximately true, as it would be for all woodwind instruments. It is particularly true for saxophones where the closed end is not as sharply conical as an oboe. The formulas for resonant frequencies appearing in the American Institute of Physics (AIP) Handbook take into account the diameters at both ends of the resonator. Nevertheless, those formulas are also approximations.
Bill
 Signature Private Profit; Public Poop! Avoid collateral windfall!
likesomepassingafternoon@gmail.com - 03 Dec 2008 20:52 GMT >>I think what you might be experiencing - and, again, I'm no expert - >>is the natural sharpness that occurs with overtones relative to equal >>temperment tuning. Hey folks,
Thanks for taking the time to reply! I understand the relationship between pure and equal tempered tuning, and this phenomenon is much different. Saxophone has n*f harmonics only for the lowest three or four fingerings, then the harmonics go wildly sharp.
Lowest fundamental on tenor saxophone: Ab, 2nd partial: Ab, 3rd partial: Eb, 4th partial: Ab, 5th partial: C, 6th partial: Eb etc. This follows the natural harmonic series:
fundamental tone F (half the keys are open) 2nd partial: F, 3rd partial: between C and Db, 4th partial: flat Gb, 5th partial: sharp Bb, 6th partial: Db?
The clarinet only has odd partials, but they go progressively flat, even when all the keys are closed. e.g.
D fundamental, 3rd partial: A, 5th partial: F, 7th partial: Bb, 9th partial: D, 11th partial: F.
Clarinetists can practice bugle calls on a Bb major triad off a D fundamental which boggles my mind.
Any acoustics texts I have read don't discuss this phenomenon at all-- maybe I can record it for you.
Ethan Winer - 04 Dec 2008 14:30 GMT > maybe I can record it for you. Or try the AP Tuner Don linked above.
Savant - 04 Dec 2008 16:33 GMT On Dec 3, 2:52 pm, likesomepassingaftern...@gmail.com wrote:
> >>I think what you might be experiencing - and, again, I'm no expert - > >>is the natural sharpness that occurs with overtones relative to equal [quoted text clipped - 26 lines] > Any acoustics texts I have read don't discuss this phenomenon at all-- > maybe I can record it for you. If you haven't come across it already, here's a JASA (Journal of the Acoustical Society of America) article that may be of interest:
"The saxophone spectrum", A. H. Benade and S. J. Lutgen, JASA, Vol. 83, No. 5, May 1988, pp 1900-1907.
In the article, the following was noted: "...slight imperfections in the air column design may displace (misalign) the resonance frequencies from the strictly harmonic relationships that are characteristic of the complete simple cone." This may help explain what (some of?) you're hearing / observing. (???)
However, FWIW, a visual inspection of the graphs provided in the article appear to point to fairly regular harmonic relationships for the tenor (and alto) saxophone, even up past the 10th harmonic. I.e., it looks as if displacements, if any, shouldn't normally cause sax harmonics to be "wildly" sharp or flat.
But, again, I'm no expert. :)
I look forward to any graphs / data you can provide. Also, I would be curious if you could provide some more detail about your observations of this. E.g., have you observed it with many different players / instruments? In many different settings? Always with increasing sharpness with increasing register? Anything else...???
Thanks,
Savant
Salmon Egg - 03 Dec 2008 06:54 GMT > > When all the keys are closed on a saxophone, the fundamental produces > > the natural harmonic series. As keys open up, and the fundamental [quoted text clipped - 5 lines] > Saxophone Harmonics: > http://www.petethomas.co.uk/saxophone-harmonics.html As in post I mad just before this, I noted that would expect the saxophone to behave more like a flute as the blown and open end diameters approached each other. To my tin ear this is demonstrated by the scale presented in the above link. The timbers at the high end sound like those of a flute to me.
> Saxophone Harmonics: Hearing with the Ears and the Embouchure: > http://www.wku.edu/~john.cipolla/saxharmonicsWKU.pdf Bill
 Signature Private Profit; Public Poop! Avoid collateral windfall!
Salmon Egg - 03 Dec 2008 05:54 GMT In article <3d7a38f1-e93c-46fe-b792-bdae196dc29d@i18g2000prf.googlegroups.com>,
> When all the keys are closed on a saxophone, the fundamental produces > the natural harmonic series. As keys open up, and the fundamental > raises in pitch, the overtones get progressively sharper. Why is this? > How does this affect our perception of the tone? Thanks for your help. > > D.B. The saxophone uses a tapered bore. You can imagine a variable instrument starting with a clarinet that has a uniform bore and varying the taper. At one extreme, it becomes like an oboe with the reed end becoming the apex of a cone.
As a clarinet, only odd harmonics of the fundamental get excited. As an oboe, both odd and even harmonics harmonics are excited. These would be the same as harmonics of a flute of the same length. The fundamental of a clarinet of that length would be half the frequency of a flute's fundamental.
The saxophone falls between the clarinet and the oboe as the taper changes. Thus, two entirely different harmonic patterns form with the saxophone in the middle. The relatively large diameter at the reed end for the saxophone means that you do not get the full effect of a closed cone end. It should not be surprising that the overtones are going to be off-pitch to some extent. How closely a saxophone's resonances follow a flute is determined by the ration of the blown and open end diameters.
If you want to get better numbers, to to the AIP Handbook where the resonant frequencies of tapered open tubes are calculated. Remember that the holes in a saxophene my be pushed a bit to give good tuning.
Bill
 Signature Private Profit; Public Poop! Avoid collateral windfall!
ttonon - 09 Dec 2008 03:09 GMT I think here are a couple important things left out of this discussion. One is the difference between sustained, forced vibration, which reaches steady-state (periodic) motion, and transient motion. With strings, and with transient motion, as in the action of a piano string or a plucked guitar string, the overtones experience significant departure from a harmonic series, due to stiffness and other effects mentioned in this thread. Bells, plates and chimes behave similarly. With strings in forced motion, however, as in a bowed instrument, the stick/slip phenomenon that maintains steady state occurs principally at the frequency of the fundamental, and of course must be periodic. This fact alone requires that all overtones be precisely some integer multiple of the fundamental. If such were not the case, the overtones would very quickly become out of step with the stick/slip process, as well as with the major string motion. Noise would result. A very fine adjustment to this statement, for the real world, is that there can be very small departures from this rule only because the overtones have a very small effect on the stick/slip process. The same is true with reed instruments, which operate in forced motion, and let's take beating reeds as an example (e.g. saxophone). The beating frequency is that of the fundamental, and all overtones must thus be precisely some integer multiple of that frequency, otherwise they would be out of step with the vibration of the reed, and with the periodic vibration of the air column, and here as well, the same refinement applies.
A second comment is that, although theoretical solutions for air column vibration in reed instruments predict, for instance, only odd harmonics in clarinets, in practice, significant contribution to the musical tone is made by even harmonics, and I think this is due to nonlinear effects in coupling the air column vibration with reed vibration. This contribution of course is not as pronounced as with the tapered bores, but it can be observed, as for instance in Benade's, Fundamentals of Musical Acoustics.
Best regards, Tom
likesomepassingaftern...@gmail.com wrote:
> When all the keys are closed on a saxophone, the fundamental produces > the natural harmonic series. As keys open up, and the fundamental > raises in pitch, the overtones get progressively sharper. Why is this? > How does this affect our perception of the tone? Thanks for your help. > > D.B.
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