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What do the words "overtones" and "fundamental" mean to you and how do you use them to describe tone?

Definition #1 - "Overtones" means sparkly upper partials and "fundamental" means smooth note.
Definition #2 - "Overtones" means echoey reverberation and "fundemental" means crisp, focused, up-front note.

By the first set of definitions a typical Collings rosewood OM has lots of overtones and a typical Martin rosewood OM doesn't. By the second set of definitions the Martin has the overtones and the Collings doesn't. By either definition Goodall has the overtones. No wonder this is one thing everybody can "agree" on. Obviously these are very different aspects of tone, and I wonder if there's a clear consensus on what these words mean in the context of acoustic guitar tone. In the world at large, the first set of definitions is accurate.

Are there combinations of these four qualities that go toward defining the terms "vintage" and "modern"?

Matt...Great topic! This should be interesting to hear everyone's comments.

As far as my understanding and usage of the terms I am a #1 believer.

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JJ
Napa, CA
http://www.DonohueGuitars.com

I do not know what you mean by smooth note.

As I understand it -
Fundamental = Base note - if you play the A (440) string, that is the fundamental.
Overtones = notes higher in pitch than the fundamental that naturally ocour.

From Wikipedia -
[QUOTE] An 'overtone' is a partial (a "partial wave" or "constituent frequency") that can be either a harmonic or an inharmonic. A harmonic is an integer multiple of the fundamental frequency. An inharmonic overtone is a non-integer multiple of a fundamental frequency.

An example of harmonic overtones: (absolute harmony)

f   440 Hz fundamental tone first harmonic
2f   880 Hz first overtone second harmonic
3f 1320 Hz second overtone third harmonic
4f 1760 Hz third overtone fourth harmonic

Not all overtones are necessarily harmonics, or exact multiples of the fundamental frequency. Some musical instruments produce overtones that are slightly sharper or flatter than the true harmonics. The sharpness or flatness of their overtones is one of the elements that contributes to their unique sound. This also has the effect of making their waveforms not perfectly periodic. Some instruments, such as tuning forks or flutes produce a clear or near perfect sound because their overtones are in very good approximation of "absolute" harmony with the base frequency.

.[/QUOTE]

_________________
"An adventure is only an inconvenience rightly considered. An inconvenience is an adventure wrongly considered." G. K. Chesterton.

Here's what I meant...

In the extreme a fundamental without overtones is just a perfect sine wave and it sounds very smooth, like the simplest electronic boop tone you can imagine. Overtones give each timbre their texture. By comparison to many other instruments, saxophones and harpsichords have tons of overtones, and that's what makes them sound jangly/sparkly.

As Steve pointed out, an overtone is any frequency above the
fundamental note. If n is an integer in the equation, then it is a
harmonic.

The collection of frequencies give rise to what we call timbre. Guitars will
have a different collection of overtones that make it unique from a piano,
etc...

However, within the realm of a guitar, I tend to think of overtones adding
to the complexity of a guitar's sound. A more complex tone will sound
richer. In my opinion, there is a tradeoff with a super complex tone - you
start to lose tonal clarity. A super rich tone might have great separation
and balance but it loses clarity. Some people love guitars like this -
especially the fingerstyle players. However, I prefer spruce soundoards
because they never seem to lose their clarity.

As far as describing guitar tone, I think the best method is to relate the
tonewood to either mahogany, maple, or rosewood and spruce or cedar.
They are familiar to most people and they sound different enough to
warrant "categories".

Peace Out,
Simon

Matt, I just read your second response. I am not sure if I agree. I have a
tuner that has an option to sound the fundamental - it sounds very
unnatural and harsh to my ears.   I think overtones tend to color a sound
and make them sound more pleasing.

I think the reason saxaphones and trumpets sound jangly is because of
the effect of the metal. Same thing with comparing a nylon guitar to a
steel string.

I think it is very possible that there are other materials out there that
produce a very "complex" wavesign but don't sound jangly - I may be
wrong tho'. In other words, there may be a correlation, but it might not
be a direct correlation.

Interesting topic.

Peace Out,
Simon

A little detail on the tone generated by a tuner. I think more inexpensive tuners would probably generate a square-wave tone digitally, which does sound harsh. Square waves are simple to generate electronically, with a minimum of components. Sine waves, which sound smoother, take more electronics to generate.

I was under the impression that overtones could be present both above and below the fundamental, but I could be wrong.

Seems that smoother-sounding instruments have overtones that are more closely related to the fundamental.

Where's Alan Carruth?

_________________
now known around here as Pat Foster
_________________
http://www.patfosterguitars.com

by physics and definition i think overtones can only be above the fundamental, at least until one begins to take into account the effects of sustain and decay.

I have always considered an overtone any harmonic resonances above the tonic(frequency?).
I have also supposed that harmonic resonances that compliment the sounded note(by western standards 3rds 5ths etc to a lesser degree 4ths and 7ths) make for a complex and richer sounding instrument,
but I feel sometimes factors combine for harmonic resonances that arent necesarily complimentary to the sounded note in cases{2nds #5ths etc}, making an instrument that sounds less pleasant by most accounts.
But Im no expert and I am sure I could be mistaken... its just how Ive always viewed it.
Cheers
Charliewood

Hey guys,
I always think of overtones and fundamental tones in a "wet" and "dry" terminology. There are exceptions of course, I have played some maple guitars that were very bright and almost wet but seemed to have no overtones. I don't like that sound. A sound full of overtones generally to me seems very wet and is usually easier to notice in a little brighter instrument. I like to think of it as being able to hear many possibilites in each chord as to where the chord will go. A drier sound, one that I would think of as more fundamental, is one where you are hearing each note of the chord separately and you can choose to hear it as a chord if you want. I think of this differently than I do balance and note separation, which could easily be talked about in the same terms. The sound I like is overtones and complexity focussed in the mid and lower mid ranges. I made one guitar that had this sound and it is the one I kept. The sound is complex in those lower tones to the point that it is difficult to tune to the harmonics on the lower three strings. I have been trying to replicate this but have had no luck. This is a topic I am very interested in.

_________________
Burton
http://www.legeytinstruments.com
Brookline, MA.

Well, I just got back in from gluing some tail inlays - and the thought hit
me. I wonder if anyone has ever really studied a guitar we describe as
more "fundamental" and one with more overtones - say like a spruce/
mahogany and cedar/rosewood instrument.

It is possible that the richer, more complex sound we think we are
hearing has nothing to do with more overtones but rather a different
arrangment of harmonics that result in the perceived, richer sound. As
Matt mentioned, the brass instruments have a complex wavesign but I
wouldn't really describe their sound as being more complex that a
clarinet or a guitar. In other words, all our talk about overtones might, in
reality, be way off.

I really haven't studied this topic at all - so I'm interested to hear what
those folks who have done so might have to say.

Peace Out,
Simon

In nature, pure fundamental notes do not exist. They always have overtones that follow them.

Instruments that tend to have more fundamental tend to sound "pure" while ones with certain overtones tend to sound more "complex". Both can sound very good and some people prefer one sound over the other.

Generally speaking, Steinway pianos are known to have more "richer" or "complex" tone compared to many European pianos which tend to have more "pure" tone. While many japanese pianos are known to have "bright" tone. They all have lots of fundamentals and lots of overtones. Just the ratio between them are different. 

The ratio between the fundamental and the harmonics/overtones (and the ratios between the harmonics/overtones) determine the sound quality of the instrument.

In general, "pure" sounding instruments do have louder fundamental over the harmonics.

In general, if you increase even order harmonics (2, 4, 6 and etc), it tend to sound more complex, while suppresing it tend to make it more pure. But also even order harmonics tend to give "warm" sound to the instrument as well, so it is not that simple to generalize the whole thing.

Increasing the odd order harmonics tend to make it harsher/percussive. For example, trumpet (or brass) tend to have more 3rd and 5th harmonics than a string insturments. It gives that brassy sound.

To me, when people says the guitar has more overtones, I tend to think that the guitar sounds "richer/complex", "brighter/sparklier". I think Olson SJ tend to have lots of sparkle and bright tone to it.

However, Taylor gutars are also bright sounding, but it lacks all the sparkle that Olson has.  While if you look at Martin OM/OOO, they tend to sound more "bluesy" with less sparkle. I consider the Martin guitars less "overtone" sounding guitars.

However, Martins probably has just as much overtone as the Olson, it is just the that ratio between it 1st, 2nd, 3rd, 4th and 5th, etc ovetones are different than the Olson's ratio, and it gives that signature sounds.

 

matt,
back to the original question and options, i've understood overtones and fundamental in the terms you use in definition #2.

i don't know anything about this stuff compared to the guys that have already posted though. i just think in terms of the guitars i've played and what i'm trying to achieve in a given instrument.

with the few world class guitars i've played, and based on a tiny sample of these instruments, i'd probably place lowden at the fundamental end of the spectrum and breedlove at the overtone end. in the lowdens (i think i've only played three so bear that in mind), i've heard clear sounding notes that stand alone and don't necessarily seem to get everything else ringing in the instrument. dry and direct is how i describe it. and i suspect that this makes lowdens ideal for amplification. not a lot of cross talk and extra noise.

breedloves on the other hand can make a guitar player feel like a piano player because of all the sound that comes of out of those things. not just the notes being played, but all kinds of extras (which i think of as overtones).

again, based on my small sample, i may very well not have lowden or breedlove pegged accurately. but this is the way i tend to think about the overtone/fundamental thing.

anyone else think of it like this?

phil

Here I am! Lots of good responses already, but you know me; can't shut up.

The terminology can be confusing, that's for sure. I'm not altogether certain I've got it all right, even now, but:

Any object that is not as simple as a rock on a string will have more than one way in can vibrate. These are the 'modes' that we talk about. The 'fundamental' is simply the lowest frequency natural mode of vibration of an object: that is, the lowest one it would make when it was allowed to vibrate 'freely'. Anything above that will be an 'overtone'.

Another term for these is 'partials': the fundamental is the 'first partial', the next one up is the 'second partial' and so on.

These don't have to have any sort of frequency relationship to each other whatever, and, in fact, there are not too many things that do normally vibrate in neat, harmonically related ways. There are two things about the way your ears work that help out here:
1) 'Close' is OK, in many cases. Gutiar strings, which provide the signal that the rest of the box chews on, don't really produce a nice clean harmonic series, and they're even worse when you tie them onto a guitar, but they're pretty close, and you get used to it.
2) If there's a lot of really awful stuff in there your ear will just throw it out, and only pay attention to the good parts. Church bells are like that: a lot of the actual power output is 'way out of whack, but your ears pick out the few partials that form something like a harmonic series, and the rest just becomes 'fuzz'.

When there are partials that are in a nice, neat, whole number relationship with each other, we call them 'harmonics'. Organ pipes are good at this.

It's possible to produce both 'objective' and 'subjective' sub-harmonics; tones below the normal fundamental. There's a way of bowing strings, for example, that makes them vibrate at some frequency that is lower then the lowest 'free' mode, but you have to force them to do it. I beleive that Tuvan throat singing is similar. Organ makers have known for a long time that if you sound a 16', an 8', a 4', and a 2' pipe at the same time, people will hear a 32' pitch, an octave lower then the lowest tone that's actually sounding. You've got all of the harmonics of that note, so the ear assumes the note is there. It's called 'English bass', and it's a nice way of making low notes when the ceiling isn't high enough for the long pipes.

There's a lot more to timbre than just the mix of overtones, although that's important. The 'hollow' sound of the bass clarinet is partly a function of the fact that it produces mostly even-order harmonics, for example. However, the 'transients'; the way the notes start and stop, have a big effect too. Some computer programs, like the old 'Cool Wave' that I use, can reverse a wave, so you can pluck a guitar string and play the sound back to front. It sounds odd. Another thing you can do is snip out a section of the sustained tone that doesn't drop off too much in volume, and loop it: you might think you're hearing a saxophone or flute.

I've been playing a lot of late with the mix of signals in the strings, and how changes in the way you build, particularly stuff on the bridge, can effect the different elements of timbre. Some of it has not been at all what I expected, but I hope I can get some more of this stuff sorted out for my talk at the ASIA meeting. Lots to do....

Great topic Matt. And just to throw another variable into the equation – just recently, on another forum I frequent, there was a question asking if anyone could recommend one brand of strings over the rest in terms of offering more overtones. Now, doesn't our sponsor D'Addario have a video ad where one of the interviewed players claims he gets more overtones and harmonics from these strings than others? I'm a big fan of D'Addario precisely for this reason (and because they still produce a “heavy” gauge 14-59) but, coupled with the 4.5 enlarged sound hole on my Larrivee slope shoulder, I hear echoey reverberations and harmonics I didn't even know existed (which makes me wonder if a side sound port would also effect the definition you're seeking to delineate). However, I wouldn't define the SD-50's voice as “sparkly” in the Taylor vocabulary, though it does “sparkle” with authority in a fundamental kind of way.

By the choices you offer in the original post, I would pick the first half of #2 and the second half of #1: Overtone means echoey reverberations and fundamental means smooth note. But then, by any definition, I'm weird.



greg

I have a question and please forgive me if I am off track in my understanding of what we are talking about here.

In an instrument like a sitar, where there are sympathetic strings being excited without being plucked, Are they being excited by a predominate fundamental tone? Playing a note on the upper strings will not excite each sympathetic string, but seemingly only the strings in some sort of "harmony" with the overiding (fundamental?) tone of the note the player plucked. I have always pictured the instrument vibrating at the fundamental tone which excited the sympathetic strings.

After reading Al's post, I am thinking that the sympathetic strings are allowing each partial to express itself (or our ears are finding those partials in a whole slew of high pitched sound?) But also, it makes me think of the guitar as a carrier of these fundamental tones while the instrument is played and how they resonate within the instrument, especially since the body, and each part to a lesser (less ability to move air) degree, can be tuned. It makes me wonder how fruitful it may be to tune each portion of the instrument (bridge, neck, rim assembly etc..) to different whole notes within the tempered system.

I have been following Al's advice and trying to match the top and back before attaching the bridge, which has helped balance the tone, but I have not been paying attention to the exact note that they are both tuned to. Could that note affect the overtones as the fundamental tone of the plucked string finds sympathy within the instrument? I understand how different wood combinations can greatly exaggerate what we all think of as overtone and fundamental, but can even those colorings be finer tuned?

_________________
Burton
http://www.legeytinstruments.com
Brookline, MA.

My question would be?how many of you play and what style?
Thats most of what your looking for in overtones!
Lance

When you pluck a string, you are activating some set of all of the partial frequencies that it can make. An easy example is to think about how you play the octave 'harmonic' of a string, by touching it in the middle to supress all of the odd-order partials that would be moving there. All you hear are the even-order partials and that makes a sound an octave higher than the fundamental of the string. The inverse happens, too: if you pluck the string in the center, then it only vibrates with the odd-order partials, since you're making it move in a place where the even-order partials don't want to be moving (this only strictly applies if the string is on a rigid mounting, and even then there are some complications, but...). So, if you pluck the string one fifth of the way along from the end, you lose every fifth partial, and so on. The string is making all of those sounds at the same time.

Every part of the guitar has resonant pitches that it really likes to vibrate at, but you can also drive things off resonance if you work hard enough at it. The 'main top' resonant mode, which works like a loudspeaker, usually at around 200 Hz, is apparently the most effective producer of sound on the guitar all the way from about 150 Hz up to around 1000. It won't be moving much at the high frequencies, but it's so effective at making sound that it doesn't take much motion.

If there's a sympathetic string attached to some part of the guitar it will vibrate at any of it's own partial frequencies if there's any shakin' goin' on. Naturally, if it's hooked up to some part that doesn't move much it will take it a while to get going, but it will. As it does it is 'sucking' energy of that pitch out of the instrument, and this has effects on the tone. For one thing, if the sympathetic string is coupled effectively to the driving string, it will take a relatively long time for the note to build up to full strength, and a long time for it to die away. Hardanger fiddles, which have sypathetic strings inside the hollow neck that touch the bridge, have a very 'sustained' and legato sound for this reason. you can't play jigs on them very well, but for some kinds of music they're great.

The trick here is that a string's partials are very narrowly defined resonances: you have to hit the pitch exactly in order for the string to get moving, unlike the top, which can be driven over a pretty wide frequency band. This is a function of the 'damping factor': how quickly the thing dissipates energy once it's been set in motion.

Any string can be a sympathetic string, of course. Playing your open low E can set the A string vibrating, since the two strings share some upper partials reasonably closely. The high E will vibrate, too, of course, and maybe other open strings as well.

I used to know a hammered dulcimer maker who claimed that it was probably a good thing you couldn't ever get them perfectly in tune. The strings are split into two segments, tuned in fifths, by a bridge. Getting one end going drives the other, and that drives another string further up, which gets its other side moving, and so forth. He suspected that if you ever tuned one perfectly it would explode from all of the strings vibrating together.