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[QUOTE=ToddStock] The experiment should be same string, same note, and different scale lengths- preferably using a pickup so that the waveform may be recorded and analyzed.

Seems like greater sustain is good for some styles and not at all what others call for. Don't think I'd want massive sustain on a figerstyle blues guitar. [/QUOTE]

That doesn't sound like any fun at all

_________________
Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

My gut says there is a direct linear relationship but my background/research is such that I can neither define the relationship or prove to myself right or not.

Then of course there is how we perceive sound?

This is one area in which I am not satisfied with my understanding

I also think when building, it is a matter of being able to feel these relationships.

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"It's a Tone Faerie thing"
"Da goal is to sharpen ur wit as well as ye Sgian Dubh"
"Sippin Loch Dhu @Black lake" ,Kirby O...

Todd If there is a difference it would not be a large difference.

_________________
"It's a Tone Faerie thing"
"Da goal is to sharpen ur wit as well as ye Sgian Dubh"
"Sippin Loch Dhu @Black lake" ,Kirby O...

Howard I think I will now down a Prozac with cougar pee an listen for tone faerie.

If anyone could help me understand things or feel I have misinterpreted relationships, input would be greatly appreciated.

_________________
"It's a Tone Faerie thing"
"Da goal is to sharpen ur wit as well as ye Sgian Dubh"
"Sippin Loch Dhu @Black lake" ,Kirby O...

I live in Canada and we're only allowed to use metric. Big penalty if caught
doing otherwise. What the heck am I suppose to do. I think Serge has been
cheating.

I really thought this was "common knowledge" but now I've been
rethinking it all day. Of course i should think something like that through
before accepting as fact beforehand....

Anyway, it does seem obvious to me that sustain would increase with
greater tension at least in the beginning of tension application. A string
with almost no tension on it is really not going to do much vibrating.
Right??? But like I said before, I would also think that at some point, a
high amount of tension might actually hinder the vibration/sustain.
Anyway, I'm quite obviously not an engineer or anything, but in my mind
the tension to sustain relationship graphed out would look like some kind
of a bell curve. And I guess that I just assumed that the peak of that was
in the range of normal guitar tunings. Maybe I'm way off though.

Another thought is that a longer string just has more area to vibrate.
Again, I'm no engineer, and I don't even have a college degree, but
suppose you have a 4" long string, I don't think it's going to sustain a
note very long no matter what tension it's at. Am I correct in thinking
this???

Can't someone just tell me the correct answer so I can stop
thinking about it?!?!?

Howard, I'd love to hear your thoughts. You can't just tweak my
"knowledge" and run         

_________________
Mike

"The Dude abides. I don't know about you but I take comfort in that. It's good knowin' he's out there. The Dude. Takin' 'er easy for all us sinners. Shoosh." The Stranger

By the way, maybe I'll try out the experiment. I do have the day off
tomorrow...

_________________
Mike

"The Dude abides. I don't know about you but I take comfort in that. It's good knowin' he's out there. The Dude. Takin' 'er easy for all us sinners. Shoosh." The Stranger

Well, my two cents. I'm more of a player, than a git-box-builder, and, I've never noticed the difference in tone, or playability of string lengths from 24 1/2" to 25 1/2". Only thing I have noticed is, when it's a radically shorter length, higher tunings work better, for instance, open D sounds good at 25" (+or-), and E sounds better on a guitar with a short scale, like 23". Also, I prefer yak piss. Alan.

I have alot of guitars around my house as I collect in addition to play and build guitars. One of the loudest instruments that I have which is surprising for its much shorter scale length is a Panormo from 1828 that has a scale length of 610mm.

I also have a Terz guitar with a 560mm scale and while the fingerboard feels much smaller, it is only a difference of s 22 inch scale length versus a ~24' for the Panormo versus a normal 650mm (~25.59") classical guitar.

Compare that to a 27" or longer baritone guitar or a 34" bass and those feel alot more vibration because of the longer wavelength of the lower frequency.

[QUOTE=Dave White]Maybe that should be "audible sustain". I just did a very quick and dirty experiment with a 0.052" string tuned to E. Plucked and listened and watched the string and counted. Then did the same with the string slackened considerably. The string seemed to continue vibrating for about the same amount of time (sustain?) but I couldn't hear it for as long.
[/QUOTE]
You may be on to something (as opposed to on something). As we've learned in the OLF classroom, sound travels more efficiently through stiffer material. That may explain why the string, when loosened, vibrated as long as it did when it was tightened, but the perceived sound diminished more quickly.

Of course, the string in your experiment retained the same mass between nut and saddle. I'm wondering if the results would be similar when the mass is reduced slightly in a shorter scale.

Sorry I said yak p..., it should have been yak pee.

What originally got me thinking about this was having a friend with a problem that made it painful for her to play guitar. She played classical guitar & played dulcimer also but had given up on playing steel strings. I started thinking about trying to build her a guitar that had the least string tension possible. Using extra Slinky's on a 24.5 scale gave me an overall string tension of 72.5 lbs almost 1/3 less than a 25.5 scale using regular Slinky's. She is not around any longer and I did not get to building the guitar. I did build her a very lightly constructed 22" scale dulcimer mahog/red cedar strung with 8s and a 16 that she really liked.

Some where along this time my enjoyable hobby became a little more serious as in wanting to be able to shape the sound of my instrument.

I do think that changing scale length does have some effect however small it might be. I want to understand it better than I do (what and why) in order visualize things and maybe use it to shape the sound of a instrument by minimizing or amplifying it.

I can't help feeling that a lot can be accomplished using the combination of string gage/scale.

I am a little self conscious about putting my thought out like this hoping to mine the thoughts and experiences of others. I guess I need to figure out a way to run experiments, share results, then discuss implications and validity.

_________________
"It's a Tone Faerie thing"
"Da goal is to sharpen ur wit as well as ye Sgian Dubh"
"Sippin Loch Dhu @Black lake" ,Kirby O...

[QUOTE=K.O.]I am a little self conscious about putting my thought out like this hoping to mine the thoughts and experiences of others. [/QUOTE]
K.,

Your thoughts and questions are perfectly valid. Everyone who wants to make a good instrument eventually comes around to those very questions.

The reduced string tension on a shorter scale does make fretting a bit easier if the string gauge remains the same. There's something else, too, that isn't often mentioned--as the scale length decreases, it makes it easier to fret ACROSS the strings, not just along them. A good example is scale lengths for classical guitars. 650mm has become an accepted standard today, but in the not-so-distant past 660mm (or longer) was often used. Many builders and players agree that the longer scale gives the guitar a richer timbre and a louder sound; so why isn't 660mm the general standard? Most players just can't, or don't want to, execute chords across the fingerboard, because the frets are too far apart. It's only a difference of 10mm, distributed over the whole fretboard, but it's a deal-breaker for most.

Using string gauges smaller than a standard "light" set for acoustic guitars (.012 - .053) is problematic. Instruments can be built light enough to get a very good sound with that gauge, but that's pretty much the limit. Wimpy tone is the reward for anything lighter than "12s". If the guitar is most always going to be amplified, you might get away with it though. If tiny-guage strings are the only way to be able to play for personal enjoyment, then that's what ya gotta do; but it will be at the expense of tone.

Carlton if you mean less volume and projection I was willing to live with that as long as I could build some richness and complexity into it. I also realized that no matter what I did it would not be much of a strummer but as she played finger-style it would not be a huge issue.

So with string tension being down in the realm of classical guitars, I thunk, take my cues from a classical guitar and use fan bracing or a hybrid short legged X-fan type scheme. The only other thing I could think of was to maximize break angle at the saddle even if I had to give it a little bit of neck angle with a tall front low backed bridge. What I was hoping to get was an intimate setting guitar with as much richness as I could build into it. Oh yea mahogany/cedar built as light as possible, carbon fiber in the neck sans truss rod. There is still a part of me that wants to build it
in order to find out if it would be successful or if I would end up with a weak muddy failure.

I did end up with questions in my mind that I still haven't answered to my satisfaction.

the effect of string tension changes on the string to saddle couple and saddle to bridge couple

the point where additional break angle stops being effective and does it change with sting tension.

and of course the ones previous in this thread.

On all these issues I feel I have a good general idea of the behaviours but there is the part of me that says that is not good enough and wants it to be nearer to a crystal clear understanding.

Thank you for taking the time to reply guys.

_________________
"It's a Tone Faerie thing"
"Da goal is to sharpen ur wit as well as ye Sgian Dubh"
"Sippin Loch Dhu @Black lake" ,Kirby O...

[QUOTE=K.O.] Carlton if you mean less volume and projection I was willing to live with that as long as I could build some richness and complexity into it. I also realized that no matter what I did it would not be much of a strummer but as she played finger-style it would not be a huge issue.[/QUOTE]
K.,

Unfortunately, it pretty much all goes away when the string gauges get too light. Especially if played fingerstyle. There seems to be a point of no return in steel-string guitars--you can build 'em light and put on a set of "12s", and have a great sounding guitar. If you build any lighter, the instrument would almost fall apart without any strings on it. Please note that I'm not an expert here, but this is what I've learned by observation over the years.

[QUOTE=K.O.] So with string tension being down in the realm of classical guitars, I thunk, take my cues from a classical guitar and use fan bracing or a hybrid short legged X-fan type scheme..[/QUOTE]
Why not just build a nylon-string quitar with steel-string dimensions (the neck may have to be a bit wider, as I noted above)? You could, in fact, make a great-sounding, easy to play guitar by going that route.


[QUOTE=K.O.]the effect of string tension changes on the string to saddle couple and saddle to bridge couple.[/QUOTE]
The higher the tension, the more force you'll get pressing down on the saddle. That's what gives us the sound we love! Too much force would probably be as detrimental to tone as too little ('cause the guitar would have to be built much too heavy).

[QUOTE=K.O.]the point where additional break angle stops being effective and does it change with sting tension.[/QUOTE]
An optimal angle was mentioned a while ago by, I believe, Alan Carruth, but I'm not sure I remember it correctly, so I don't want to lead you astray.    Maybe an archive search for "break angle" would be effective. I think I'll do that myself.