Engineer comments

Robert Delahunt

Showmasterologist
I asked an engineer today at work, whose specialty is vibration analysis, about some guitar related stuff. I found out some interesting info. Just some conclusions I drew:

1) More dense = more inertia for a string or vibrating object to overcome, but more sustain once set in motion. I sat there for a while analyzing the engineering formula for inertia as applied to a vibrating string between two points. More mass means more inertia, so while it may be more resistant to being set into motion initially, once set into motion it will take more for it to be dampened.

2) Ways to get more sustain: hit the string harder (more initial force), pluck it more towards the center of the string (force in the equation is modified by where it impacts the string), and make the two points between which the string is suspended more resistant to being moved (one way: making them more dense, since more mass means, again, harder to set it into motion, but then also harder to dampen the motion).

3) All other things being equal, thicker strings require more tension to tune them to pitch. This could both cause strings to not vibrate as long compared to their thinner cousins, but also mean that they vibrate longer due to mass in the form of inertia. The jury's still out: I'd need to calculate the dampening effect of the string due to tension and then the amount of inerta the string would have, since those two factors will be combating each other.

4) It's nice that electric guitars are electric, but ultimately, this means that the wood will have a small effect on overall tone. True, it will have an effect, but the wood is more of a damper that has other resonant frequencies, so it will color the tone, but sucky wood will have sucky tone. Case in point: maple is more dense than swamp ash, which gives it higher sustain (since it resists motion being transfered to it more, thus sort of reduces the dampening of string motion by the body), but you may not like the overtones it has due to its internal resonant frequencies.

5) More mass means more inertia applies to floating tremolos. For example, an aluminum tremolo block and such will be less dense than nickel or steel, meaning that you will get less sustain, or should, all other things being equal. Callaham's tremolo blocks should, then, be better for sustain. Also, a six-point tremolo block bolt pattern should get less lost sustain to the dampening of other factors, but the jury is still out.

The most I got to was the "how much vibration will you get based on string and force". Bottom line, however: more sustain should come from having end fulcrums (i.e. string nut and bridge) that are more resistant to vibration (i.e. their larger mass / resonant frequency tends to reflect energy back to the string rather than dampen it). Also, the last thing we found together was that if you have strings and a bridge / nut that are the same material, you should get better sustain, all things being equal. If you can afford a nickel steel string nut and saddles that are the same alloy as "pure nickel" strings, you should get nice sustain, all other things being equal.

Lastly, yes, when I told the engineer how pickups were made, he agreed that they could be essentially acting as magnetic dampeners if too powerful, so more sustain should come from weaker magnets and/or magnets farther from the strings, but again, there's no one "magic bullet" for getting huge sustain: too many factors.

I'll start digging into more math monday :D
 
Last edited:
Re: Engineer comments

4) It's nice that electric guitars are electric, but ultimately, this means that the wood will have a small effect on overall tone.

Can I get a double eye roll smiley??? :rolleyes: :rolleyes: :nono:

Once you get this engineering stuff out of you, you can sit down and listen to different electric guitars acoustically and hear the difference between woods and construction hands down. <-------- this also means when your plugged into an amp!
 
Re: Engineer comments

Can I get a double eye roll smiley??? :rolleyes: :rolleyes: :nono:

Once you get this engineering stuff out of you, you can sit down and listen to different electric guitars acoustically and hear the difference between woods and construction hands down. <-------- this also means when your plugged into an amp!

I'm not trying to start problems. However, compared to an acoustic instrument, the wood plays less of a factor in an electric guitar. That's all I'm saying.
 
Re: Engineer comments

yes, and the only thing you need to account for is that each of those parameters is also frequency specific with a different resonance at each frequency
 
Re: Engineer comments

I don't need an engineer to tell me that real men use 11's. LOL

LOL well I'm using 10s on the Showmaster regardless. 9s on my Lite Ash still sound incredible, ironically. But I was going to get into that next time as well: how much tension on the strings applies to how fast you can fret a note, or at least how much pressure you'd have to exert to fret it.
 
Re: Engineer comments

I can speak from experence when I say heavier strings sustain a lot better.

I like the feel of 11s a lot but I don't like that much tension on a thin neck. Fine for my tele though.
 
Re: Engineer comments

Inherently all the Engineering in the world is primarily flawed in that you're unable to take into account that you're dealing with wood which varies from tree to tree.

Science has been trying to figure out why the Stradivarius violins sound the way they do and failing miserably at it.

Additionally each player is different, the angle of the pick, the density of flesh, the way they play. These are all variables which can make any absolutes in Physics be wholly defeated.
 
Re: Engineer comments

-Sustain is overrated :D
-Kids play 9 strings :D
-Good resonant wood make your pickups "hotter" :D
 
Re: Engineer comments

Inherently all the Engineering in the world is primarily flawed in that you're unable to take into account that you're dealing with wood which varies from tree to tree.

Science has been trying to figure out why the Stradivarius violins sound the way they do and failing miserably at it.

Additionally each player is different, the angle of the pick, the density of flesh, the way they play. These are all variables which can make any absolutes in Physics be wholly defeated.

I'm not trying to make this out to be "engineering is the key to the universe". However, if failing miserably is a .1% difference, you're a sad person indeed. Engineering isn't perfect, but .1% isn't enough difference between paper and reality to be worried. Remember, these people are the ones that helped prove the "old guitar player" legends and such to be factual and not hogwash.
 
Re: Engineer comments

Everyone at the Duncan forum knows that weaker magnets give you more sustain. ;)

I also like to point out a few things, obviously a trem has a certain mass and is coupled to both the body and the springs. Some of the vibration is transferred to the springs, decreasing sustain. Hence why a hardtail sustains longer than a trem. Also, you say nut, bridge and string material should be the same. Why does everyone forget that the nut is only the fulcrum on open strings? You must include the frets too.

And to the guys that say "just play it!", you're missing a key point... Some of us nerds LIKE discussing this stuff. :D
 
Re: Engineer comments

Inherently all the Engineering in the world is primarily flawed in that you're unable to take into account that you're dealing with wood which varies from tree to tree.

Science has been trying to figure out why the Stradivarius violins sound the way they do and failing miserably at it.

Additionally each player is different, the angle of the pick, the density of flesh, the way they play. These are all variables which can make any absolutes in Physics be wholly defeated.
What you are missing Skarekrough, is general trends, not specific examples. Generally, maple is denser than alder, so generally it will have a brighter sound. And what you find? That it does. Sure, some examples fall out of the "tolerance" for their species but most are within a range.

But on the other hand, you're right in the sense that our ear can detect minute differences in tone that can be very difficult to pinpoint the exact cause of, since there are so many variables at work.
 
Re: Engineer comments

I have found that on nights when I'm sitting around drinking some beer and jamming that my sustain drops drastically! On nights were I DON't drink, it hangs for days... you can go grab a bite to eat come back and it's still "AAAAHHHHHHH".....

I'm certain this is due to the lack of density in my tummy when I'm full of beer and got a bit of a spare tire sag.... as opposed to the nights I have washboard abs that don't absorb the inertia!
 
Re: Engineer comments

I just want to put a word in favor of my pet theory, and that is sympathetic resonance. My idea is that too stiff and dense of an instrument will actually require the string to stretch to vibrate, thus restricting motion. Whereas a flexible and resonant instrument will enhance string vibration, increasing sustain beyond normal limits.

Now, this is all based on the fact that in my experience, the most 'alive' electric guitars have the longest sustain. I just put together a Warmoth baritone guitar with a Wenge neck and black Korina body for a friend, and it is so alive it feels like it grabs the note after you pick it and swells it. The ADSR almost resembles a Rhodes or something. This compared to a Samick artist series with set neck and hard ash body that's so stiff and dense it seems to almost swallow the notes as I pick them.
 
Re: Engineer comments

It does seem counter-intuitive... but I know what you mean... a tighter and brighter guitar can seem to require more work to make it talk... looser darker axes seem to just mesh and compliment your fingerwork....
 
Back
Top