The Gibson ES-335 has f-holes. These guitars were famously used by BB King, his own named Lucille.
When Gibson made a signature model he asked to remove the f-holes to reduce feedback:
> The most noticeable differences between the Lucille and the Gibson ES-355TD-SV on which it is based are the "Lucille" script on the headstock, the maple neck, and the lack of F-holes on the top. King requested that, to reduce feedback, there be no F-holes.
Some do, but the bodies of guitars (with the exception of archtops) are built differently from violins. Namely, the top and bottom of a violin are carved (the thickness ranges between 3 and 8mm), whereas the guitar has a mostly uniform thin (0.5 - 1mm) sheet of hardwood with support bars.
One of the big reasons for the different style of top is that a bowed violin string produces much stronger vibrations than a plucked guitar string, so the body of a guitar must amplify the sound much more than the body of a violin.
Archtop guitars with carved tops usually do. Flat-top acoustic guitars have a complex bracing system that would get in the way of F-holes (nylon string guitars are usually fan-braced, and steel string guitars, with more tension, are X-braced).
Seems a touch to aesthetically pleasing to be truly optimal, given they have a partial fitness function in terms of radiated power I wonder what a GA would come up with.
There's your chance to out-run Stradivarius. The thing you're going to have to deal with next is how your improvement weighs in against playing an instrument for a few hundred years. You might be able to work this out by comparing a brand new regular violin with your improved model in a series of double blind tests for preference and then do the same thing every couple of years afterwards to see if there is a diverging trend.
One possible problem here is that the appreciation for classical music is not exactly on the rise and really high quality violins have limited applicability elsewhere. It's a matter of time before there will be more quality violins than violinists (and most of them will live in China where there is a fairly large continent of classical performers, and their numbers are actually on the rise).
The only comment there makes a very good point, the c shape has a 'tab' of wood and if that runs along the grain of the top then it can easily break off, the f shape does not have that property. So maybe what started out as a mechanical improvement actually turned out to work better because the vibrations are divided more evenly to the sides of the hole.
In addition, the corners at the top and bottom of the C are stress risers, encouraging the propagation of cracks from those points. There's nowhere for a crack to start on an f-hole. I'm sure the old luthiers were not only experimenting with tone quality, but also with repair issues.
That's one of the characteristics of evolution of any sort... things don't really happen for this reason or that reason, they happen because of all the reasons all together sort of jostling around and interacting with each other and the solutions and the problems created by those solutions and so on. Even when on occasion one particular change can be pinned to a particular reason, that's the exception rather than the rule and it still is a participant in the jostling.
(This is elaboration on the point, not disagreement.)
Somewhat off-topic, but this is basically the idea behind "exaptation." Something develops through evolution for one reason, but is found to be superior for a different reason. For example, it is widely believed that feathers evolved purely for warmth, however their structure enabled certain animals to fly.
I saw on TV last night a throw-away line from a teacher in a drama [1] about "survival of the fittest", and how only the strongest genes survive. I just cringed.
I realize that this is how people conventionally think about it, and on the surface it's only subtly different from the real explanation, but the result is that it makes you think about the evolutionary process in a fundamentally incorrect way.
I think this is a big part of why people fail to understand how emergent systems pop up all over the place. It leads to the mistaken idea that, for example, being able to design a new economy is just an engineering problem, and we can just paste together what seems to work with our own bright ideas, and get something functional out the other end.
Isn't the subtle difference only hanging on the 'survival' word? The best suited genes for the situation get expressed. The fact that other genes are lurking around waiting for their opportunity, doesn't deny the point of the dialog.
Well, that too, but the most important thing is the cost to carry a particular adaptation/mutation. If it's low enough, then it won't get thrown out by the pressure of natural selection. If it's beneficial, then it'll get selected for (so it'll spread in the population). That's one way how seemingly uninteresting adaptations have spread, they got lucky and coincided with a useful mutation.
So evolution is an optimization process. On a constantly changing landscape.
Also that the fitness function applies to the system as a whole. So a trait that's just amazing at something, but carries a large cost, may not be able to survive. I guess that's kinda what you said, just phrased differently.
And this is getting away from the central point, but there's also much debate (at least at the level I'm reading; maybe it's solved by now for those in the field) about how traits can support a community at the expense of the individual - like with old humans losing the ability to procreate.
Ok I've always wondered if maybe our old-age feebleness was adaptive! It means the old folks sit around the fire with the young folks, and teach. Once social groups began, that could really boost a community at the cost of a declining agility in old age.
Feebleness in old age is simply run down machinery, otherwise there would be no old age, we'd feel the same all our lives long until we died of some kind of accident or ritual murder of those that outlived their welcome.
True. Yet other mammals have different clocks; other creatures seem to have no clock at all. So our clock is set by genetics. Why at this rate? That's the idea I was getting at.
No. When you say "the best suited" or "the strongest", that implies that the most optimal state has been reached by evolution, and that isn't the case at all.
The only thing evolution does is favor one adaptation over another. At that point in time, a particular mutation/adaptation may work out better (though frequently due to pure chance), so it survives and gains inertia. Inertia is a very powerful thing; it's why we have a lot of big companies that don't seem to do that well, laws that don't make much sense, etc. Once something is in place, it's hard to change it. The same thing is true of evolution. It does not always result in the most optimal configuration, or even frequently.
There's plenty of examples of things in the human anatomy which are actually terrible "design" choices, but when viewed through the lens of evolution, make sense. A famous example is some nerve (I forget the name now) that takes a ridiculous and non-sensical route, but when you look at the history of how we evolved, it makes sense that it got stuck there because of what came before. It's like that with a lot of human technology too; train tracks, for instance, weren't spaced at their current spacing (gauge) because it was the optimal design choice (esp. not now with modern trains and cargo sizes), they did it because technologies and tooling and infrastructure that came before made it easier to use that gauge than to switch to something different. If we could change things, it'd make more sense to increase the standard gauge on most railways, but there's too much inertia and it'd cost too much.
Well can we simulate a violin? If so, it seems we could run an optimization algorithm (genetic algorithm, simulated annealing, etc.) to see if the evolution could be continued. Analogous to machine evolved antenna designs (where NEC is the simulator).
It's interesting that pre-electronic instrument design was pretty much all about increasing loudness.
I play double bass, and in Chuck Traeger's book on bass repair, he is pretty blunt: "You get paid to be heard." Loudness is definitely a quality factor with a direct influence on price.
Instruments with a sweet tone quality, but lacking in volume, are a tough sell, and will often be modified to bring out more sound. With the exception of a few museum pieces, the Strads have all been modified over the years to make them louder, with longer necks and shorter ribs.
I suspect the cello edged out the viola da gamba because of volume.
Oh, I have to promote my friend Noah's human powered electronic instrument, the "Electric Eel". It's no so easy to have sufficient loudness with even with electronics:
It uses re-purposed printer carriage with stepper motor to generate electricity. With very low latency, the pulse of power boots a synthesizer and powers the audio amp.
+1 for a Chuck Traeger reference on HN. I'm also a double bassist. Agreed about instrument modifications. It's common in the bass world for a big-sounding instrument to be described as a "cannon". That doesn't speak much for having a singing tone! Maybe in the world of violins and cellos that's more important, though.
'Just one minor gripe: period instruments -- Strads/Amatis -- that have been upmod'ed, have only been modified with regard to the pitch/angle of the neck. The fingerboard is longer to facilitate the more demanding repertoire, but the neck is certainly the same length. The ribs are not shortened nor elongated in modernizing a period instrument.
Intriguingly, it hasn't been a continuous upgrade, like computers, etc. There was at least one major stratum in this evolution when patronage for music shifted from the church to the court. With larger audiences required to financially support the music, instruments went through a major shift of amplification to use more metal parts, etc.
I also like your idea of continuing to optimize the designs. Some people are also trying different materials like carbon fiber! One issue with the simulations is that people don't comprehend the structure of wood perfectly. It's only recently that researchers have realized the importance to the sound of the wood being a non-continuous material and actually comprised of long, irregularly-shaped grains. Most of the papers I've seen are analyzing instruments and trying to figure out what the salient features are of the design.
One more caveat is that it still has to be easily buildable. The current design is excruciatingly difficult and slow.
So one thing this illuminates for me is how much instrument design is like biology :)
I studied cello performance at my university and delved into the world of instrument design when searching for my current cello with its low-five-digit price tag. It is a pretty cool blend of art and science.
Folks on HN might like to check out the work of Joseph Curtin, a MacArthur grant recipient from my hometown. He publishes acoustic research and makes world-class instruments (i.e. mid-to-high five-digit prices). http://josephcurtinstudios.com/
The holes in acoustic string instruments are not there to "allow sound to escape". Sound radiates in all directions from the surface of the instrument, although the frequency balance may change from point to point. Consider drums, for example. A drum may be completely sealed, yet still work and still make sound.
The purpose of soundholes is tuning the resonant frequency of the acoustic chamber. Google Helmholtz resonators for the theory and math if you like. The area and depth of the port alters the resonant frequency, which is largely a function of volume.
Acoustic guitars usually have large, circular holes. When recording acoustic guitars, you should never point the microphone at the soundhole! You'll get a dull, woofy, severely unbalanced sound. There are many mic techniques to deal with the frequency issues, but the most common is a microphone along the neck, aimed backward at the neck/body joint. That wouldn't work if the sound just escaped from the soundhole, as the article implies.
I don't think it's entirely wrong, at least for violin-family instruments.
If I put my hand near the f-holes on my cello while I play, I can feel a shocking amount of airflow in and out of the body.
The sound emitted by the holes is indeed unbalanced because that's dominated by the resonant frequency of the instrument, but that's a large part of what gives the instrument such acoustic power.
...
Additionally, it does make sense that the sound is more efficiently emitted by narrow holes with lots of edge area: it's like the skin effect in electrical conductors at high frequencies, where most of the current flows near the surface of wires, rather than in the bulk.
The air is flowing because it's a tuned resonator, not because it's making sound. That's how the tuning port works. Sound does come out of the hole, but only incidentally. Its value is tuning the chamber, not releasing the sound. The sound would be radiated regardless, conservation of energy and all that.
I think the F shape has a lot more to do with limiting mechanical stress points for cracking. A round hole with the same area as the f-holes would weaken the top and create changes in how the soundboard vibrates. It's different on a flat-top acoustic guitar, where bracing rather than carving governs the strength of the top, and bracing also limits the valid locations for soundholes.
Energy is conserved, but you may end up with heat instead of sound. Also, sound near an object behaves differently. As you stand further back you get constructive and destructive interference between different parts.
Beyond that we operate on a logarithmic scale when it comes to sound, what sounds slightly louder to us can be heard over much larger areas.
My unscientific opinion as a guitarist is that thermal loss isn't a dominant factor. Most of the energy put into the instrument is converted to sound.
Admittedly, guitars are different from violins here, but... with a guitar, there's a pretty fixed amount of energy transmitted when a string is plucked. This energy may radiate quickly or slowly. In other words, there's a tradeoff of attack and sustain. An exaggerated case it the banjo. A banjo is loud, but has little sustain. An unplugged Les Paul electric makes little acoustic sound, but sustains for many seconds. Within the narrower world of acoustic guitars, small-bodied guitars tend to be apparently louder, but not as rich as large-bodied guitars, due to this attack/sustain tradeoff.
From experience, an acoustic guitar is about as powerful volume-wise as 1/2 to 1 watt electric guitar amp with a moderately efficient speaker. And there just isn't a whole lot of energy transmitted from a guitar pick to a string. Whatever the efficiency is, there aren't wide variations in acoustic guitar volume that can't be explained by the attack/sustain tradeoff.
Bowed instruments get around the attack/sustain tradeoff by having continuous energy input, so the attack strength can be sustained for the duration of a note.
My cello is particularly resonant, and in hindsight (is this confirmation bias talking?) has very little sustain on pizzicato (plucking) compared to my cheap, less-resonant student cello.
Energy conservation doesn't come into play, because unlike on a plucked instrument, the bow is there continually supplying vibration. If more of it gets emitted, then more of the bow's energy goes into vibration instead of friction.
On the other hand, with a guitar, the more efficient a radiator it is, the louder it is but the less it sustains, because each pluck imparts a fixed amount of energy to the instrument.
When I was learning violin, I used to mess around with my violin to understand how it worked (it was a very cheap one). One of the things I noticed was the covering the holes with paper changed a lot the tone of the instrument but very little the power of it.
Also, my violin teacher had a couple of superb (and very expensive) old violin. And there was a lot of variation in the shape of the f from instrument to instrument. Different f-holes give different "character" to the sound but the impact on the power was really limited.
One of the things I noticed was the covering the holes with paper changed a lot the tone of that instrument but very little the power of it.
That's why violin mutes, which allow a violinist to practice quietly, attach to the bridge...to reduce the transfer of vibration to the chamber via the sound post and bass bar...
If you'd like to experience (hear) the subtle variations between two violins that are, proportionally, almost identical--that is, they're "tuned resonators", listen to this exchange between Ali Bain and Nicola Benedetti, two very talented violinists, discussing their instruments...
> A drum may be completely sealed, yet still work and still make sound
although I am not sure about the rest of your comment, this is not true, for the most part. Most drums will have some hole in them (usually either somewhere on the side or the entir bottom) to let air go in and aout of it as the drum heads resonate. of course they would still make sound with out these holes, it changes the sound quite drastically :)
Yep - I was exaggerating to make a point a bit. Although there are folk drums that are totally sealed (African talking drums, for example), the drum kit toms and snare that most people think of as "drums" are vented. It's not really the same as a tuned resonator like a violin, though. The vent is just there to ease pressure and keep the heads from choking on the attack.
Still, it gets across the idea that sound doesn't come out of the hole, but rather radiates from the entire instrument.
I don't think that's quite right. Half of the vibrating surface area of a hollow stringed instrument is on the outside, and half is on the inside. If you close up the soundhole, you'll lose quite a bit of volume just for that reason.
I was reading a long series of articles by a maker of fine violins, and he pointed out that what we are looking at is not a pair of holes, but the two edges of a single resonating area on an instrument which has been decoupled from the instrument on two sides.
I found that a very helpful when understanding the design of these instruments.
There's one more factor to consider: The f-hole determines the shape of the belly itself, and the division of the belly into smaller sections by the bridge, soundpost, and bassbar, is thought to contribute to the tone of the instrument.
No major piece of a violin serves just one purpose, and all of the pieces interact. What a glorious mess.
Aren't f-holes a common style choice for electric hollow-bodies in general? Maybe they're all just copying Gibson's example as well, but I can't remember the last time I saw one that had any other shaped sound holes.
62 comments
[ 2.7 ms ] story [ 138 ms ] threadWhen Gibson made a signature model he asked to remove the f-holes to reduce feedback:
> The most noticeable differences between the Lucille and the Gibson ES-355TD-SV on which it is based are the "Lucille" script on the headstock, the maple neck, and the lack of F-holes on the top. King requested that, to reduce feedback, there be no F-holes.
https://en.wikipedia.org/wiki/Lucille_%28guitar%29
There's a very good song by him talking about Lucille:
https://www.youtube.com/watch?v=-Y8QxOjuYHg
One of the big reasons for the different style of top is that a bowed violin string produces much stronger vibrations than a plucked guitar string, so the body of a guitar must amplify the sound much more than the body of a violin.
One possible problem here is that the appreciation for classical music is not exactly on the rise and really high quality violins have limited applicability elsewhere. It's a matter of time before there will be more quality violins than violinists (and most of them will live in China where there is a fairly large continent of classical performers, and their numbers are actually on the rise).
(This is elaboration on the point, not disagreement.)
I realize that this is how people conventionally think about it, and on the surface it's only subtly different from the real explanation, but the result is that it makes you think about the evolutionary process in a fundamentally incorrect way.
I think this is a big part of why people fail to understand how emergent systems pop up all over the place. It leads to the mistaken idea that, for example, being able to design a new economy is just an engineering problem, and we can just paste together what seems to work with our own bright ideas, and get something functional out the other end.
[1] Freaks and Geeks
So evolution is an optimization process. On a constantly changing landscape.
And this is getting away from the central point, but there's also much debate (at least at the level I'm reading; maybe it's solved by now for those in the field) about how traits can support a community at the expense of the individual - like with old humans losing the ability to procreate.
https://en.wikipedia.org/wiki/Kin_selection
tl;dr: those in the community have almost the same genes as you, so helping them is almost as beneficial as helping yourself.
The only thing evolution does is favor one adaptation over another. At that point in time, a particular mutation/adaptation may work out better (though frequently due to pure chance), so it survives and gains inertia. Inertia is a very powerful thing; it's why we have a lot of big companies that don't seem to do that well, laws that don't make much sense, etc. Once something is in place, it's hard to change it. The same thing is true of evolution. It does not always result in the most optimal configuration, or even frequently.
There's plenty of examples of things in the human anatomy which are actually terrible "design" choices, but when viewed through the lens of evolution, make sense. A famous example is some nerve (I forget the name now) that takes a ridiculous and non-sensical route, but when you look at the history of how we evolved, it makes sense that it got stuck there because of what came before. It's like that with a lot of human technology too; train tracks, for instance, weren't spaced at their current spacing (gauge) because it was the optimal design choice (esp. not now with modern trains and cargo sizes), they did it because technologies and tooling and infrastructure that came before made it easier to use that gauge than to switch to something different. If we could change things, it'd make more sense to increase the standard gauge on most railways, but there's too much inertia and it'd cost too much.
It's interesting that pre-electronic instrument design was pretty much all about increasing loudness.
Instruments with a sweet tone quality, but lacking in volume, are a tough sell, and will often be modified to bring out more sound. With the exception of a few museum pieces, the Strads have all been modified over the years to make them louder, with longer necks and shorter ribs.
I suspect the cello edged out the viola da gamba because of volume.
https://www.youtube.com/watch?v=I8MUgwiZULw
It uses re-purposed printer carriage with stepper motor to generate electricity. With very low latency, the pulse of power boots a synthesizer and powers the audio amp.
> increasing loudness.
Intriguingly, it hasn't been a continuous upgrade, like computers, etc. There was at least one major stratum in this evolution when patronage for music shifted from the church to the court. With larger audiences required to financially support the music, instruments went through a major shift of amplification to use more metal parts, etc.
I also like your idea of continuing to optimize the designs. Some people are also trying different materials like carbon fiber! One issue with the simulations is that people don't comprehend the structure of wood perfectly. It's only recently that researchers have realized the importance to the sound of the wood being a non-continuous material and actually comprised of long, irregularly-shaped grains. Most of the papers I've seen are analyzing instruments and trying to figure out what the salient features are of the design.
One more caveat is that it still has to be easily buildable. The current design is excruciatingly difficult and slow.
So one thing this illuminates for me is how much instrument design is like biology :)
Folks on HN might like to check out the work of Joseph Curtin, a MacArthur grant recipient from my hometown. He publishes acoustic research and makes world-class instruments (i.e. mid-to-high five-digit prices). http://josephcurtinstudios.com/
The holes in acoustic string instruments are not there to "allow sound to escape". Sound radiates in all directions from the surface of the instrument, although the frequency balance may change from point to point. Consider drums, for example. A drum may be completely sealed, yet still work and still make sound.
The purpose of soundholes is tuning the resonant frequency of the acoustic chamber. Google Helmholtz resonators for the theory and math if you like. The area and depth of the port alters the resonant frequency, which is largely a function of volume.
Acoustic guitars usually have large, circular holes. When recording acoustic guitars, you should never point the microphone at the soundhole! You'll get a dull, woofy, severely unbalanced sound. There are many mic techniques to deal with the frequency issues, but the most common is a microphone along the neck, aimed backward at the neck/body joint. That wouldn't work if the sound just escaped from the soundhole, as the article implies.
If I put my hand near the f-holes on my cello while I play, I can feel a shocking amount of airflow in and out of the body.
The sound emitted by the holes is indeed unbalanced because that's dominated by the resonant frequency of the instrument, but that's a large part of what gives the instrument such acoustic power.
...
Additionally, it does make sense that the sound is more efficiently emitted by narrow holes with lots of edge area: it's like the skin effect in electrical conductors at high frequencies, where most of the current flows near the surface of wires, rather than in the bulk.
I think the F shape has a lot more to do with limiting mechanical stress points for cracking. A round hole with the same area as the f-holes would weaken the top and create changes in how the soundboard vibrates. It's different on a flat-top acoustic guitar, where bracing rather than carving governs the strength of the top, and bracing also limits the valid locations for soundholes.
Beyond that we operate on a logarithmic scale when it comes to sound, what sounds slightly louder to us can be heard over much larger areas.
Admittedly, guitars are different from violins here, but... with a guitar, there's a pretty fixed amount of energy transmitted when a string is plucked. This energy may radiate quickly or slowly. In other words, there's a tradeoff of attack and sustain. An exaggerated case it the banjo. A banjo is loud, but has little sustain. An unplugged Les Paul electric makes little acoustic sound, but sustains for many seconds. Within the narrower world of acoustic guitars, small-bodied guitars tend to be apparently louder, but not as rich as large-bodied guitars, due to this attack/sustain tradeoff.
80 decibels, ~= 0.001 watts of energy. https://en.wikipedia.org/wiki/Sound_energy_density_level
PS: And yes most home speakers ~1% efficient. https://en.wikipedia.org/wiki/Loudspeaker#Efficiency_vs._sen... At scale they can get into the 20% range, but even that suggests guitars are probably not that efficient overall.
My cello is particularly resonant, and in hindsight (is this confirmation bias talking?) has very little sustain on pizzicato (plucking) compared to my cheap, less-resonant student cello.
On the other hand, with a guitar, the more efficient a radiator it is, the louder it is but the less it sustains, because each pluck imparts a fixed amount of energy to the instrument.
Also, my violin teacher had a couple of superb (and very expensive) old violin. And there was a lot of variation in the shape of the f from instrument to instrument. Different f-holes give different "character" to the sound but the impact on the power was really limited.
That's why violin mutes, which allow a violinist to practice quietly, attach to the bridge...to reduce the transfer of vibration to the chamber via the sound post and bass bar...
F-holes are simply one element of the whole violin, a part that contributes to an elegantly refined proportionality...
https://www.youtube.com/watch?v=zgDNSDadqos
although I am not sure about the rest of your comment, this is not true, for the most part. Most drums will have some hole in them (usually either somewhere on the side or the entir bottom) to let air go in and aout of it as the drum heads resonate. of course they would still make sound with out these holes, it changes the sound quite drastically :)
Still, it gets across the idea that sound doesn't come out of the hole, but rather radiates from the entire instrument.
I found that a very helpful when understanding the design of these instruments.
I'm fun at parties.
No major piece of a violin serves just one purpose, and all of the pieces interact. What a glorious mess.
Precisely...