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This has been on my mind for some time.

Brass players discuss the strength of partials extensively. But I've never been sure when they were really hearing it, or when they were fooling themselves.

We know that the brain has an almost infinite capacity to fool itself, e.g. to see patterns that aren't there.

When piano tuners are listening for partials, are you sure you are really hearing them? Or sometimes might you be imaging them?

Yes, I hear them too. But I even doubt myself!

What do you think they sound like? What do you think they should sound like?

The way I understand it, partials change the timbre of the note. With no partials, it would sound like a tuning fork, or maybe a flute.

One of the things that brass players listen for is (when playing together) the "sum tones" that should (theoretically?) be heard when certain intervals are played.

One way to get an idea of what particular partials sound like for a particular note: Download the demo version of Pianoteq. There is an equalizer (called the "Spectrum Profile") that allows you to adjust the intensity of various partials (numbered 1 through 8).

Of course, it's a simulation of a piano, but it may provide something of an idea of the role a specific partial plays in the tone of a given note.

Yes, I am absolutely sure I am really hearing them. What is there to imagine? The upper partials are indeed there at all times along with the fundamental - sometimes in very annoying ways, and other times in absolutely beautiful ways.

If you want to experience (and believe) this for yourself, all you need to do is experiment on a grand piano by touching the strings lightly along various segments of the length of string with one finger while you strike the corresponding key with the other hand to create partials that are much more audible. In fact, by segmenting (dividing) the string at various positions along its length, you can emphasize certain partials over others, while simultaneously emphasizing the upper partials themselves much more than the 1st partial, or the fundamental pitch.

If it's someone else's piano you should first get permission to touch the strings, and you may want to avoid touching the copper-wound bass strings or your fingers may create tarnish marks that are impossible to remove. Be sure to thoroughly wash and dry your hands before touching any strings, and don't press down hard. I often do tap/pluck on bass strings and treble strings with fingers and soft objects but I get permission first when its not my piano and I make sure my hands are squeaky clean.

I believe that all I hear is there. The problem is that I don't hear all the sounding partials.

Some days ago, I was returning home with my son, 13 years old, and when we get into the house my son told me:

- You forgot to turn off the TV!
-How do you know?
-Because I hear it
-What are you hearing?
-Teeeeeeeeeeeeeee......!

I couldn't hear nothing. I went to the TV room, the decoder was off and the TV was on, so there was no audio and no image!

So the sound was to high in frequence for me to hear it. But not enough for my son, who told me "it's gone", when I turned off the TV.

Hi. Tim. Judging by the ammount I use them in the course of tuning, I must have a great imagination if, after all these years they turn out to be not real. Many people seem not to hear them and suggest that it's in my imagination when I teach tuning principles, even musicians. For my own experience, the interaction between partials when I tune a major third always sound to be coming from lower in the harmonic spectrum than theory tells me to listen. Any other tuners experience them this way?

Beautifully put! They're there. The bigger problem for me is trying to hear them and having them not come through clearly or at all on those poorly-scaled spinets.

It is possible I have a fundamental (pun) misunderstanding of what piano tuners hear.

Yes, brass instrument tones contain a fundamental (usually, not always) and a series of overtones.

The ear assembles them into a perceived fundamental pitch with a perceived timbre. When I hear a Bb on a trombone, I think Bb, and I perceived it as bright or dark depending on the content of the overtones. I know intellectually what the series of overtones is, but I don't normally listen for them, because the sense of timbre gives me the information I need.

Some brass players listen specifically for various overtones (we call them partials) within that note. With effort you can isolate them. But there's always been some controversy over how much that effort may cause you to imagine them. This isn't a simple ear test, but involves some brain processing, and given the state of the average trombone player's brain we can anticipate some error potential. <g>

Beats are something else. Of course we hear beats and use them to tune, and of course we are aware those beats may be the product of overtones rather than the fundamental.

From following this forum, I had come to the conclusion that piano tuners actually listen for specific partials above the note they're banging on, not just the beats produced by them. Now I'm not so sure I understood correctly.

This happened at our church with an older (now retired) organist.

He told the tuner not to bother with the top 4 notes, they didn't work anymore. The tuner said yes they do, please play them so I can adjust the pipes.

They called me over, I brought my children. All of us could hear them. The organist could not.

What were these 4 notes? C8 is under 4,300 hz.

I have heard that our hearing threshold lowers with age. But I can hear tones well above C8.

The frequency range of human hearing is 20-20,000 hz. that is E0 to F#13.

Musicians fool themselves a lot. The musical world is full of hearsay, and musicians like myths.

Musical theory has gone through many transformations and it's not rare to see people being told things that were proved to be false many decades (if not centuries) ago.

Now, partials are real. Since you asked in this forum, yes, piano tuners work with them all the time. The interference between specific partials guide you when turning pins. You might not be paying attention to partials per se, but to beats. But you can actually listen to partials if you pay attention to single notes (just don't expect to be able to do what Sauveur said.

I think it was Joseph Sauveur who said he could hear (at least?) the first 128 partials in the harmonic series if he paid attention (yeah right, not possible at all... and yet he complained about musicians living in a world of fairy tales).

Ask a string player to show you what "harmonics" are. Search this forum for "ghosting" (slowly depress a key in a piano without making that note sound, and then play a ff stacc. note one octave above, then try an octave + a fifth, etc. you should also try intervals not in the harmonic series).

Gadzar is right about high frequencies and how our hearing changes with time, that is very real.

I am 27.75 years old and I can still hear that tv sound he mentioned. I can still hear the very high pitched ring tones used by teenagers so their teachers won't be able to know when their cell phones are ringing. That won't last forever

Hearing threshold

Now, about things that are not actually there...

About the tones mentioned by david_a: combination tones

The missing fundamentals are also a very important phenomenon: missing fundamental

Combination tones and missing fundamentals aren't actually there, but we can hear them. There are many more interesting unreal but real things in psychoacoustics: auditory illusions

You are right: "the brain has an almost infinite capacity to fool itself, e.g. to see patterns that aren't there." I'd not say that is a bad thing, we need some way to "organize" the data we get. Perception is a fascinating thing.

While on this subject I am curious about what was already mentioned about higher firquencies: I have never taken measurements but do you think that on a piano - partials exist that have a frequence above our audiable range of hearing? Most likely.
Next question: Do you think that we respond to them - when tuning or listening? More than likely.
How so? With our ears or with our brain's ability to fill in where our ears fail?
Your thoughts?

The horizontal deflection frequency of an American (NTSC) tv is 15750 Hz. Our ability to hear high frequencies deteriorates as we age and there are several free online hearing tests avilable to see how well you do. The better tests like this...

http://www.phys.unsw.edu.au/jw/hearing.html

let you relate the threshhold amounts to dB levels. I can still hear the tv sound at 48 y/o but my threshold has dropped by a few thousand hrtz over the years.
Personally, I would like to know if people with tinnitus who experience self induced high pitched whistling sounds can actually hear beats from their relationship to external coincidental partials of say a piano string. If this is true than its quite possible that we are hearing beats, but they are not fully caused by the piano and its coincident partials.

I've made the test, I have no headphones so I used two external speakers and then the results are not very significative.

But one thing is sure: I don't hear the 16 kHz tone, even at 0 dB.

I hear fine from 12kHz down to 30 Hz.

Here it is confirmed, I can't hear the TV, but I can still tune pianos without hearing aids! 12kHz is higher than the 5th partial of C7.

I know a singer, who presumably suffers tinnitus. That singer claims to use this "inner voice" as a guide to hit a specific note. Apparently, the tinnitus is close to that specific note (it is apparently slightly sharp, so the singer "aims" below that "sound").

This is hearsay, of course, and I don't know of this directly from the singer, but from some students and friends of that person.

To make this account even less reliable: we are talking about a singer! It's not like they like drama and stories, or to make stuff up to spice things a bit.

Getting back to the question first asked, mostly I listen for beating, which is the sum and difference of partials, including the fundamental. But I also listen with a “sense of pitch” which is a very subjective thing.

I remember a few years ago listening to the 4th of July concert in Washington D.C. on PBS. They had Barry Manilow and Arethra Frankiln each perform (to their own recordings, I presume…) Barry did not stretch his octaves much, if at all, and seemed to really sing in ET. Arethra stretched to the limit and sang the notes at whatever pitch suited her. They probably would not have sounded like themselves otherwise.

The closer I tune to the ends of the piano, the more I favor my “sense of pitch”. I suppose I really am tuning with partials in this case, and not just listening to beats. Lately, I have been using twelfths in the top octave by playing the lower note first and then tuning the upper to where it sounds on pitch. I am guessing that my brain locks in on the third partial of the lower note as there is a very narrow window where the note sounds right. But when trying to do the same thing with octaves, the window is much larger. I am guessing that my brain is picking up the additional audible partial matches that octaves have that twelfths do not.

But with wound notes I can definitely pick out individual partials, especially when some are more strident.

Hey, I resemble that remark!