What is timbre and can we measure it?

[IPunchCholla]

Without "coupling" you don't hear anything. The most desired requirement in room coupling would be that whatever coupling there is doesn't degrade a signal's timbral signature to the point of where the timbre is unrecognizable or ambiguous. If we could think of timbre like (vowel) formants, identifying its significant components might then become more tractable.. (Familiarity with the "singer's formant" might help, here.)



I would recast the above as "room coupling is an unavoidable (potentially minor) part of how the sonic spectrum is formed." (N.b., room might be unbounded - outdoors; also notice ADRS's absence.) Going on, room coupling only becomes an issue when the inherent resonances interfere with crucial formants. My media room is a good example. Prior to installing clouds over the LP, speech was difficult to understand, owing to cancelations - a product of LP, speaker position, and room geometry. To make this problem description "timbral," one need only parameterize the positions and room geometry. That is, a room has timbre, but its effect (on reproduction) is mostly felt where potentially interfering (or disruptive) resonances intersect with source (speaker) and/or receiver (listener) positions. With a spinorama (or similar) derived timbral model, timbre becomes 3d and it gains specificity. This would mesh well with a general model of timbre that recognized the importance of dispersion (directivity) to timbre.

Like I said earlier, timbre is a lot more complicated than it appears, and simple metrics probably won't crack its nut.

Wait. Are you discounting ADSR from timbre entirely?

 

[IPunchCholla]

Without "coupling" you don't hear anything. The most desired requirement in room coupling would be that whatever coupling there is doesn't degrade a signal's timbral signature to the point of where the timbre is unrecognizable or ambiguous. If we could think of timbre like (vowel) formants, identifying its significant components might then become more tractable.. (Familiarity with the "singer's formant" might help, here.)



I would recast the above as "room coupling is an unavoidable (potentially minor) part of how the sonic spectrum is formed." (N.b., room might be unbounded - outdoors; also notice ADRS's absence.) Going on, room coupling only becomes an issue when the inherent resonances interfere with crucial formants. My media room is a good example. Prior to installing clouds over the LP, speech was difficult to understand, owing to cancelations - a product of LP, speaker position, and room geometry. To make this problem description "timbral," one need only parameterize the positions and room geometry. That is, a room has timbre, but its effect (on reproduction) is mostly felt where potentially interfering (or disruptive) resonances intersect with source (speaker) and/or receiver (listener) positions. With a spinorama (or similar) derived timbral model, timbre becomes 3d and it gains specificity. This would mesh well with a general model of timbre that recognized the importance of dispersion (directivity) to timbre.

Like I said earlier, timbre is a lot more complicated than it appears, and simple metrics probably won't crack its nut.

If a French horn is played in an anechoic chamber, does it not have timbre?

 

[Titurel]

Wait. Are you discounting ADSR from timbre entirely?

Have been pretty consistently from the beginning, calling it a closely related phenomena but neither a subset or superset of timbre. Some have raised mild objections for me pointing out the obvious, that gas tank and waffle cone were quite separate from gasoline and ice cream. (Metaphoriphobia?)

 

[Titurel]

If a French horn is played in an anechoic chamber, does it not have timbre?

Sure it does. Just not much of a resonant signature, and where do you propose we hang the mike? I think a better question would be, "does a French Horn played in a vacuum chamber have a timbre?" My answer would be, "No, I don't believe it would, nor would I volunteer to test the hypothesis."

 

[RayDunzl]

"does a French Horn played in a vacuum chamber have a timbre?"

Assumng the room is a 100 cubic meters and the vacuum pump is turned off:

According to AI, which I use to perform strange calculations beyond my payscale, only 0.18 average lungfull of air (creating 0.1 pascals of pressure) would need to be introduced by the player playing the horn for sound to begin to be transmitted.

So, there's that, as a partial answer.

If there is a sound coming from a musical instrument it would have a timbre.

 

[Titurel]

Assumng the room is a 100 cubic meters and the vacuum pump is turned off:

According to AI, which I use to perform strange calculations beyond my payscale, only 0.18 average lungfull of air (creating 0.1 pascals of pressure) would need to be introduced by the player playing the horn for sound to begin to be transmitted.

So, there's that, as a partial answer.

If there is a sound coming from a musical instrument it would have a timbre.

Clearly I should have included a smiley in my post.

 

[Axo1989]

Without "coupling" you don't hear anything. The most desired requirement in room coupling would be that whatever coupling there is doesn't degrade a signal's timbral signature to the point of where the timbre is unrecognizable or ambiguous. If we could think of timbre like (vowel) formants, identifying its significant components might then become more tractable.. (Familiarity with the "singer's formant" might help, here.)

So, you are thinking of timbre as formant which is usually defined as a broad peak, or local maximum in the spectrum. Thus disregarding/excluding the envelope. Makes sense (in terms of your argument/definition).

Have been pretty consistently from the beginning, calling it a closely related phenomena but neither a subset or superset of timbre. Some have raised mild objections for me pointing out the obvious, that gas tank and waffle cone were quite separate from gasoline and ice cream. (Metaphoriphobia?)

I've pointed out previously though that the ADSR time envelope isn't a container really, it just looks a bit like one on the spectrogram. It's really just an artefact of the complex onset and decay of the sound event. We infer an envelope where sound is absent on the xy axes. And it's useful to describe time-domain characteristics of the event in overall terms.

That said, I've seen timbre defined as you do, absent the time envelope. But in that case, why not just call it spectrum?

 

[Axo1989]

I don’t see how that’s the case. That seems like an unnecessary slippery slope argument.

Timbre is the phenomenon by which we can distinguish different sounds, through features like different harmonics, and overtone combinations, attack, and decay, resonance, etc.

“Timbre” is often used in describing musical instruments yes. But it’s a set of real world phenomena that is hardly confined to instruments.

If I have a drumstick and I tap my wooden kitchen table, and then I tap a metal pan, we will be able to differentiate between those sounds. Why? It will be due to largely to the difference in Timbre - differences in harmonics and overtone combinations, attack, and decay, resonance,

It’s the same phenomenon, so why would we use a different word for it?

Likewise, if you compare the sound of a single violin playing a note versus a mass of violins playing the same note (even at the same volume ) how will you tell them apart?

If it’s not by the same qualities known under the term Timbre?

Yes, I don't understand the anxiety behind the slippery slope. Timbre is the complex character of a sound event, of course it can be broken down into its multiple aspects or components. How could it be otherwise?

It’s almost like saying that we shouldn’t use the same term “red” to describe both a car painted red and a flower that is red. Because that would be somehow confusing.

You're on to something here. Cars are macho. Flowers not so much. Heaven forbid we talk about flowers then.

 

[Axo1989]

Where the hell is this going to end????????????????

Another theme song then:

 

[Titurel]

So, you are thinking of timbre as formant which is usually defined as a broad peak, or local maximum in the spectrum. Thus disregarding/excluding the envelope. Makes sense (in terms of your argument/definition).

It also made sense to me because our auditory systems seem to have evolved to process sound in those terms.

(BTW, I appreciate the direction you've taken with this discussion.)

I've pointed out previously though that the ADSR time envelope isn't a container really, it just looks a bit like one on the spectrogram. It's really just an artefact of the complex onset and decay of the sound event. We infer an envelope where sound is absent on the xy axes. And it's useful to describe time-domain characteristics of the event in overall terms.

Sure, define (or denote) time in its appropriate unit, ditto for intensity, rise time, whatever. But without some 'deliverable' they are constraints constraining nothing. BTW, i wasn't even thinking about what an envelope looked like in a spectrogram, even though I've seen plenty of them, going back as far as 1975.

There are clear, simple, compact schemes for denoting the individual elements of ADSR and none (really) for the rest of it, that ineffable thing I would call timbre.

That said, I've seen timbre defined as you do, absent the time envelope. But in that case, why not just call it spectrum?

Why not spectrum? A couple millennia of tradition and a connection to the wider world of art outside audio engineering. Besides, spectrum does not suggest or imply structure, whereas timbre (or formant) does. Spectrum is a constraint or range, which is possibly why some are moved to roll it in with things that are obviously constraints. Timbre in (formal) audio engineering is IMO an inapt borrow or a term best used only in casual discussion.

 

[Titurel]

Are we going to include every descriptive term in audio under the aegis of "timbre"?

Frequency response doesn't equal timbre, but it's a component of it.
Resonance doesn't equal timbre, but it's a component of it.
Harmonic distortion doesn't equal timbre, but it's a component of it.
Intermodulation distortion doesn't equal timbre, but it's a component of it.
Phase distortion doesn't equal timbre, but it's a component of it.
Beat frequencies don't equal timbre, but they're a component of it.

I agree wholeheartedly.

Where the hell is this going to end????????????????

It will probably end soon after people stop asking questions.
As to where? Good question.
Consensus would be nice, but highly unlikely.

 

[Galliardist]

I don’t see how that’s the case. That seems like an unnecessary slippery slope argument.

Timbre is the phenomenon by which we can distinguish different sounds, through features like different harmonics, and overtone combinations, attack, and decay, resonance, etc.

“Timbre” is often used in describing musical instruments yes. But it’s a set of real world phenomena that is hardly confined to instruments.

If I have a drumstick and I tap my wooden kitchen table, and then I tap a metal pan, we will be able to differentiate between those sounds. Why? It will be due to largely to the difference in Timbre - differences in harmonics and overtone combinations, attack, and decay, resonance,

It’s the same phenomenon, so why would we use a different word for it?

Likewise, if you compare the sound of a single violin playing a note versus a mass of violins playing the same note (even at the same volume ) how will you tell them apart?

If it’s not by the same qualities known under the term Timbre?

It’s almost like saying that we shouldn’t use the same term “red” to describe both a car painted red and a flower that is red. Because that would be somehow confusing.
Why not? You can understand they are different things and yet identify the phenomenon of “ red colour” also applies to each.

I don’t see how it’s confusing at all If you simply identify what you were talking about.
On one hand, I’m talking about the timber of a single violin note and on the other hand I’m clear about talking about the timber of massed strings.

The various definitions of timbre that I can find fall into three groups - music, general, and other scientific definitions.

The whole thing is, as you may expect, a mess. I've become less certain what is actually meant by timbre as I go along.

Standard texts on music give some quite strict definitions of timbre as the property of an (one) instrument, Then a hundred pages later, orchestras, music of different periods, and so on are described in terms of timbre, in clear violation of the author's own definition. The Oxford Concise Dictionary of Music does a similar thing. If you read articles you find that a group of instruments can have timbre, yet the definition of timbre itself says it is the sound quality of 1 (and the copy we have uses the number) instrument. (Some editions apparently shorten the word instrument to inst. as well).

So, I chose to hang onto the idea of timbre as the quality that allows you to recognise the source of a sound, and the quality of sound. Then timbre is assigned to a "complex event" in other definitions. At this point, unless we are going to hang onto a specific science - acoustics, or phonetics (timbre has a different definition set there as well) - we may as well give up on the definition. I'm clearly using a different definition to others here, while some people are switching definitions to make points.

We can always talk about tone quality (another part of definitions in music), or simply the "sound", since we are clearly concerned beyond just recognisability of the sound when it comes to high fidelity, as your post on loudspeaker choice indicates. Timbre in itself is a poor term to us in this context. Could you rewrite your posts in this thread without using the word timbre and make as much sense? - I'd say yes. I think that proposal probably applies to the majority of posts in this thread.

So we can't simply define timbre, and different working definitions arbitrarily allow or deny the answer to your questions. In informal discussion of music, I think we could say yes to both points, but that doesn't help us with measuring the quality specifically in reproduction.

It seems that timbre is just too confusing a word to use formally and give an answer in the sense that @DesertHawk wants, to be able to measure it.

I continue to propose that standard measurements should cover "timbre" as it is a property of sources that have been recorded, but there may be subjective considerations involved as always.

 

[Titurel]

I continue to propose that standard measurements should cover "timbre" as it is a property of sources that have been recorded, but there may be subjective considerations involved as always.

I think we may have reached a Potter Stewart moment for timbre. Regarding hard core pornography, Supreme Court Associate Justice Stewart wrote that it "was hard to define, but I know it when I see it."

 

[kemmler3D]

That said, I've seen timbre defined as you do, absent the time envelope. But in that case, why not just call it spectrum?

There's an envelope that's inherent to the instrument to an extent (harpsichord can never have a soft attack) but there's also an envelope that depends on how you play a given note, which to an extent I'd say you could separate from timbre. For example, if you hold a note longer that doesn't necessarily impact timbre meaningfully, but is a major factor in the envelope of the note.

So, I chose to hang onto the idea of timbre as the quality that allows you to recognise the source of a sound, and the quality of sound.

This is close to the definition I carry around in my head. "Timbre is what makes instruments sound unique." This naturally comprises many physical components, each of which can be measured, but as a gestalt / subjective experience, timbre cannot be reduced to single factors or measured per se.

I guess this also opens a lot of debate around the margins of what contributes to timbre...

I still don't think it opens a debate on whether speakers or rooms or whatever have timbre, simply because those things aren't instruments.

They sound unique, and they are even involved in music listening and performance, but that doesn't mean they have timbre any more than sports cars do - which are also valued for their unique sounds.

 

[Axo1989]

Likewise, if you compare the sound of a single violin playing a note versus a mass of violins playing the same note (even at the same volume ) how will you tell them apart?

Standard texts on music give some quite strict definitions of timbre as the property of an (one) instrument, Then a hundred pages later, orchestras, music of different periods, and so on are described in terms of timbre, in clear violation of the author's own definition. The Oxford Concise Dictionary of Music does a similar thing. If you read articles you find that a group of instruments can have timbre, yet the definition of timbre itself says it is the sound quality of 1 (and the copy we have uses the number) instrument. (Some editions apparently shorten the word instrument to inst. as well).

Apropos of this part, my thesaurus goes straight to the orchestra:

timbre
noun
the Czech orchestra have just the right timbre for Smetana. tone, sound, sound quality, voice, voice quality, colour, tone colour, tonality, resonance, ring.

Not definitive obviously, but typical of the variation in informal definitions. Personally I still favour the 'complex character of a sound event' angle, per Schouten or several of the papers discovered via @Timcognito's query. And applicable most anywhere from instrument to ear. But I'm interested in acoustics, and sound in general, experimental music and so on, and I don't play an instrument (acoustic instruments are an historical curiosity with odd cultural persistence after all). Others will obviously choose definitions that align with their own experience, focus and interests.

Could you rewrite your posts in this thread without using the word timbre and make as much sense? - I'd say yes. I think that proposal probably applies to the majority of posts in this thread.

Interesting thought. But why wouldn't selected synonyms work? That's what they're there for.

 

[Axo1989]

It also made sense to me because our auditory systems seem to have evolved to process sound in those terms.

But there's no way you can argue that our auditory system eschews envelope or onset of a sound. It's a key part of recognition.

Sure, define (or denote) time in its appropriate unit, ditto for intensity, rise time, whatever. But without some 'deliverable' they are constraints constraining nothing. BTW, i wasn't even thinking about what an envelope looked like in a spectrogram, even though I've seen plenty of them, going back as far as 1975.

Yes, there are obvious gaps in your thinking on this aspect.

There are clear, simple, compact schemes for denoting the individual elements of ADSR and none (really) for the rest of it, that ineffable thing I would call timbre.

Why not spectrum? A couple millennia of tradition and a connection to the wider world of art outside audio engineering. Besides, spectrum does not suggest or imply structure, whereas timbre (or formant) does. Spectrum is a constraint or range, which is possibly why some are moved to roll it in with things that are obviously constraints. Timbre in (formal) audio engineering is IMO an inapt borrow or a term best used only in casual discussion.

I don't follow this proposition of spectrum as 'constraint'? Or absent 'structure'. By spectrum I'm also thinking of the graph posted by @MAB. Which shows us a time-slice of the timbre of sound from that instrument, under two conditions. That's what you posit as timbre in toto, yes? Or did I miss something ...

 

[Galliardist]

Apropos of this part, my thesaurus goes straight to the orchestra:



Not definitive obviously, but typical of the variation in informal definitions. Personally I still favour the 'complex character of a sound event' angle, per Schouten or several of the papers discovered via @Timcognito's query. And applicable most anywhere from instrument to ear. But I'm interested in acoustics, and sound in general, experimental music and so on, and I don't play an instrument (acoustic instruments are an historical curiosity with odd cultural persistence after all). Others will obviously choose definitions that align with their own experience, focus and interests.



Interesting thought. But why wouldn't selected synonyms work? That's what they're there for.

I never thought to check a thesaurus, and I turned to music dictionaries in the first instance because that was what fitted the discussion best when I got here. As a player of a historical curiosity, but also from other discussions of the subject, I prefer to think of timbre as a property of the object making the initial sound, which allows modifications of that sound to be considered separately. This fits nicely with both "historical curiosity" music and with music/sound reproduction, since we are often discussing modifications to the sound of instruments and voices through the recording and playback process.

It seems though that timbre has been an "available word", one where someone comes along and picks it for whatever thing to do with sound quality that they are trying to describe. it was when I found the phrase "timbre of the classical period" that I gave up.

 

[Titurel]

But there's no way you can argue that our auditory system eschews envelope or onset of a sound. It's a key part of recognition.

Perhaps I should have been clearer. I was suggesting (strongly) that our auditory systems evolved to recognize formants, specifically vowel formants, that attribute of phonation that allows a child's or woman's vowels to be recognized as the same vowels spoken by a mature man, even though the pitch of the two utterances be an octave or more apart. I could give a more complete explanation, but I fear that would get us too far off topic Unambiguously analyzing envelope is child's play by comparison.

Yes, there are obvious gaps in your thinking on this aspect.

Again, I may not have been clear enough. Seeing an envelope in a spectrogram was not "interesting" or useful re the topic, then or now. What I saw and what continues to interest me are formants, band of energy which by virtue of their presence and spacing denote vowels (and perhaps timbre?) quite independent of pitch. (Autotune, funky as it is, works by virtue of this phenomenon.)

I don't follow this proposition of spectrum as 'constraint'? Or absent 'structure'. By spectrum I'm also thinking of the graph posted by @MAB. Which shows us a time-slice of the timbre of that instrument, under two conditions. That's what you posit as timbre in toto, yes? Or did I miss something ...

Spectrum, as in the range of something, e.g., the visible (or audible) spectrum and, by extension the placement of "features" within that gamut (gamma ut, per Guido D'Arezzo). Since there are features both above and below a particular spectrum, it is de facto a constraint.

 

[CedarX]

This thread is a chaos!

Most valuable post for me:

Timber:

See Merriam-Webster: https://www.merriam-webster.com/grammar/the-strange-case-of-timber-and-timbre

So, ‘timbre’ as “the quality of a sound made by a particular voice or musical instrument” only exists in English since the 1800s.
And prior to that………?????
Voices or musical instruments had no ‘timbre’? After all, the word did not even exist…

Problem A: What is ‘timbre’—the word !!!

 

[MattHooper]

This thread is a chaos!

Most valuable post for me:

View attachment 421961

See Merriam-Webster: https://www.merriam-webster.com/grammar/the-strange-case-of-timber-and-timbre

So, ‘timbre’ as “the quality of a sound made by a particular voice or musical instrument” only exists in English since the 1800s.
And prior to that………?????
Voices or musical instruments had no ‘timbre’? After all, the word did not even exist…

Problem A: What is ‘timbre’—the word !!!

Ironically, this post has confused me more than any other post on the thread.