Does guitar shape affect tone ?

[jeremy3220]

Slightly off topic -- the top frequency is lower than the back. You can hear it just by giving the back then top a knock.  Sounds like a difference of a little over a step on my LV-03r.

Here's another great thread from Alan Carruth.
http://www.luthiersforum.com/forum/viewtopic.php?p=187583&sid=a9af51562feaa1aa320b11af17499d78#p187583

[cke]

Sorry to hear that cke. Hope you feel better soon. I didn't realize you were asking how  guitar shape affects tone. Sorry for my sarc. 

No I found it cleaver 

Dang Dude! Hopefully, next week is lots better!

Thanks 

[rockstar_not]

@gitnoob,

you know - sometimes they will run you out of a forum thread if you try to bring too much science into the discussion.  Just sayin'. 

BTW, your descriptions have seemed spot-on to me.

-Scott

[L07 Shooting Star]

@gitnoob,

you know - sometimes they will run you out of a forum thread if you try to bring too much science into the discussion.  Just sayin'. 

BTW, your descriptions have seemed spot-on to me.

-Scott

For what it's worth, I like bringing the science into the discussions.  After all, how else can some of these things be explained?  Old wives tales?  Physics exist for a reason.  Could we put a man on the moon otherwise?  Just sayin'

Kurt

[rockstar_not]

For what it's worth, I like bringing the science into the discussions.  After all, how else can some of these things be explained?  Old wives tales?  Physics exist for a reason.  Could we put a man on the moon otherwise?  Just sayin'

Kurt

Well there are some topics here (multiples of them over multiples of years) that just seem to live on in perpetuity that have no basis in physics of acoustics and vibration as well as physiology of hearing.  To suggest that any of them aren't based in reality can start a flame war.  I won't even call out one of them here because I don't want to start another war.  My post was somewhat tongue-in-cheek but I don't see an emoticon for that.

-Scott

[ducktrapper]

Well there are some topics here (multiples of them over multiples of years) that just seem to live on in perpetuity that have no basis in physics of acoustics and vibration as well as physiology of hearing.  To suggest that any of them aren't based in reality can start a flame war.  I won't even call out one of them here because I don't want to start another war.  My post was somewhat tongue-in-cheek but I don't see an emoticon for that.

-Scott

Oh you mean like why a guitar using very similar designs, woods, builds should cost two or three times more than similar guitars with a different name on the headstock and how come people are so willing to pay?  

[Mr_LV19E]

For every action there is a equal and opposite reaction.

[L07 Shooting Star]

Well there are some topics here (multiples of them over multiples of years) that just seem to live on in perpetuity that have no basis in physics of acoustics and vibration as well as physiology of hearing.  To suggest that any of them aren't based in reality can start a flame war.  I won't even call out one of them here because I don't want to start another war.  My post was somewhat tongue-in-cheek but I don't see an emoticon for that.

-Scott

I indeed intrepeted your post as "tongue in cheek".
I think you and I are actually on the same page.  The point I was trying to make was that I need to see some scientific explanation that makes sense to me before I will believe any of these hairy fairy theories (not based on science) you refer to.  So, in a thread such as this, I appreciate and enjoy the posts that try and demonstrate, with real factual information, the physics going on.  If such a post dispells or contradicts some of these long-held, traditional "factoids", that's fine with me.  If it gets me "flamed" I'm OK with that too.  Helps me make more informed decisions.

Beside, I'm kind of a geek when it comes to this kind of stuff. 

[jeremy3220]

This video may contain unsavory language but is humorously related to the science discussion.
http://www.youtube.com/watch?v=_-agl0pOQfs

[Danny]

It's all about herding cats who are totally ignoring you because they're trying to decide whether to eat the chicken or the egg.

Or herding butterflies.

Physics can define the answer, but the number of parameters would make the equation obscenely complicated, and in the end, the answer would be something like "42".

42... That number is very significant. ie "The completion of sufferings"

Science should be objective, but listening is subjective. Science gives you helmholtz frequencies; listening gives you music.

Earplugs help while shopping at Guitar Center

For a lot of players its easier to simplify the physics by talking about the parts of the guitar that effect the most audible differences. But the subjective nature of playing will always make it hard to know if you are really hearing the guitar you're playing (defined by sound) and not the guitar you think you are playing (defined by emotional attachment to a certain body style, bracing, wood, etc. etc. etc.).

"Well... There you go again." R.R.

Body styles have tendencies toward certain timbres and balances, but a good luthier could adjust for those, to the point where you'd be delighted with any number of different body styles (as long as you were physically comfortable playing them). Shear volume (sound pressure) may be different between body styles, but anyone who's played with a bad drummer knows that volume ain't all its cracked up to be.

Let alone BANJOS

Considering that these discussions always revolve back to experience,  it is good to remember the frequently overlooked scientific baselines that should be talked about: where are people playing these instruments and when?

Empirical evidence is the bottom line here.

You make some good statements and I enjoyed your post, I hope you don't mind my "coloring". 

[jeremy3220]

Science should be objective, but listening is subjective. Science gives you helmholtz frequencies; listening gives you music.

For a lot of players its easier to simplify the physics by talking about the parts of the guitar that effect the most audible differences. But the subjective nature of playing will always make it hard to know if you are really hearing the guitar you're playing (defined by sound) and not the guitar you think you are playing (defined by emotional attachment to a certain body style, bracing, wood, etc. etc. etc.).

The physics has nothing to do with guitar players nor does it require listening. Builders can study and work with the physics of guitar building without worrying about the subjective nature of playing. It's not that what you said isn't true but what you're saying isn't countering the science argument; rather you're only diluting it by trying to show it is part of a bigger system which we cannot grasp.


We can know things,
Jeremy

[gitnoob]

People have studied both the physics of guitars and the psychoacoustics of listening to guitars.

If you're interested, here's a PhD thesis on the subjects:
http://www.hakwright.co.uk/thesis.html

[peterh]

AS A NEWBIE you might like these

  :nana_guitar

I am afraid to say that I am interested in both but then I can find stuff like scale theory interesting too!   Which means its just another blinkin variable and so which shape suits is just up to yerself,  knowing why isn't necessary but can be just interesting!

have another from me 

[cke]

AS A NEWBIE you might like these

  :nana_guitar

I am afraid to say that I am interested in both but then I can find stuff like scale theory interesting too!   Which means its just another blinkin variable and so which shape suits is just up to yerself,  knowing why isn't necessary but can be just interesting!

have another from me 

My my, a wise newbie... Hooda thunkit?   

Actually, I too enjoy both science and art. My suspicion is that all of our instruments were evolved by highly skilled and intuitive artisans, and the science came later to try to explain what they were/are doing. My question at the beginning was to learn more about guitars, having never played a jumbo that wasn't a 12 string, and wondering if there were tonal advantages in addition to their attractiveness for shape/appearance as compared to a dread shape. Luthiers have ways of drawing out from any shape the sound  that they prefer. The shape of the soundboard would seem to have a significant contribution. I am in rapture of the tone my L-09 has, from its bassy bottom to its OM - like top.  Its shape is vaguely Jumbo-esque, and I wondered if the lower bout contributes to the one and the upper bout to the other.  All of your posts have been good food for thought and I appreciate it.

[lmacmil]

For what it's worth, I like bringing the science into the discussions.  After all, how else can some of these things be explained?  Old wives tales?  Physics exist for a reason.  Could we put a man on the moon otherwise?  Just sayin'

Kurt

Haven't been in this forum long but on AGF, science is a dirty word to some.  They know what they hear and no amount of scientific evidence that says a certain change is inaudible will convince them otherwise.  Questioning someone's ability to hear a change is like questioning their manhood, no good can come from it. 

[unclrob]

Though I don't care either way I was wondering if there are any builders out there building based on and using the science available to them to actully build guitars and I'm not talking about CAC or CNC stuff but act true computer science and physic to build.


Also I'm not trying to make trouble,just wondering as I do what I do based on what I've been taught and things I've learned on my own as a repairman.Sometime's I call it reverse enginneering.

[abalone at last]

Maybe something like this............................

http://www.guitarnoize.com/blog/comments/emerald-guitars-9-string-carbon-fibre-fan-fret-acoustic-guitar

[unclrob]

Nah thats not what I'm talking about.Fiber guitars are just a different material and fan frets have been around forever.I asking is there any builder building base on science and physics to construct a guitar.Is there a real math formula designed based on what phsyics dictates ie;dimention,top thickness,side thickness etc?You know real science stuff,real physics,not another trick market pony.

[rockstar_not]

Nah thats not what I'm talking about.Fiber guitars are just a different material and fan frets have been around forever.I asking is there any builder building base on science and physics to construct a guitar.Is there a real math formula designed based on what phsyics dictates ie;dimention,top thickness,side thickness etc?You know real science stuff,real physics,not another trick market pony.

unclrob, we got into this a few months back regarding compensated saddles.  Fan fretted instruments and compensation at the saddle ARE based on real science and physics on transverse wave motion.  If you want to look at the formulas, I can haul them out.  Or you can have a look online.  It's kind of hard to type them in with a text-only editor here.  The wave frequencies are based on length, tension, cross sectional thickness, density, and other factors and fan fretting CAN provide a more accurate tuning for fretting along the length of the string, as do compensated saddles.  Don't tell me that when you re-string an electric guitar with different gauge strings than what were on there before, you don't change the saddle distance from the nut or from the top of the guitar than where they were before.  If you do this, then you are using some of that physics - whether you know the equations or not.

Back several years ago, Garrison guitars from Canada did a great job using engineering know-how and physics to re-think the way that the string vibration translated through the guitar.  Garrisons sounded quite nice, but man were they heavy!  There is no overall single formula for all of this, however.  It's an integration of mode shapes of the top and the equations that govern that, the transverse wave equations of the strings themselves, the equations governing the coupling of those systems, the equations governing the mode shapes of the air as it vibrates inside the guitar, etc.  Connecting all of the equations together in a single mathematical model that works in a predictive fashion is nearly impossible.

-Scott

[unclrob]

In a lot of case's I don't change the intonation because the distance between the nut and the bridge has not changed.I do have to change the slotting.As for the Garrison Guitars I'm not really sure it was done for the purpose stated or for the ease of build and really good marketing.Non the less they didn't get far but thats another story.



:cop:I'm sure that many will think that anything that I will ever post again will have any credability after the above statement and I know I will either be ignored by more people or my posting will never have merit.I understand the science behind the fan frets and it works and is also physics and I also understand that when a builder works the wood to his/hers desired effect that physics is involved even if they're not using a math. formula to get there.I'm also not pooh poohing the science but I do believe that there is much more then science involved.So if I've distroyed my rep here,Sa La Vee.I hope I spelled that right.