VSL Breakpoint Angles, Radiuses, and Excess String Lengths

Strumelia
Strumelia
@strumelia
3 weeks ago
1,767 posts

Folks, please stay on Nate's thread topic and don't take over the thread to introduce other subjects. I have removed a few off topic posts.
Does anyone have more to add to actually answer Nate's questions?  If you have other things to discuss then please start a new thread specific to that subject in the appropriate location. And please be clear and specific about your discussion subject if you start a new thread. Thanks.




--
Site Owner

Those irritated by grain of sand best avoid beach.
-Strumelia proverb c.1990

updated by @strumelia: 05/10/20 02:45:42PM
Strumelia
Strumelia
@strumelia
3 weeks ago
1,767 posts

Question posed by the original poster:

NateBuildsToys:

This might end up being a controversial topic, since I cant seem to find a lot of agreement on it elsewhere, but I'd like to know what y'all know and have observed about how much the headstock angle, length of the headstock, radius of the nut, and bridge breakpoint angle, radius of the bridge, and excess of string between the bridge and tailpins affect tone, volume, and sustain...

...In the attached image the black objects represent 'bridges' the red lines represent 'strings'. The first diagram shows a 'bridge' with very minimal contact, which I believe puts tremendous amounts of extra stress on the bridge and the string. The second shows better contact but still a sharp angle at the breakpoint, which i believe can cause intonation issues and buzzing since the string might not actually be able to bend all the way to match the angle of the bridge without over-applying string tension, and therefore the breakpoint may be further back on the bridge than intended. The third diagram is what I currently do more or less, which is round off the side of the bridge and nut that is outside the VSL so that the string has a lot of contact and no sharp angles. I have never paid attention to the length of string outside the VSL, I have always assumed that if you have adequate downward force on the bridge and nut, that anything past them is irrelevant. A lot to think about but I'm sure plenty of you have thought about these things before! I'd love some more perspective




--
Site Owner

Those irritated by grain of sand best avoid beach.
-Strumelia proverb c.1990
Robin Thompson
Robin Thompson
@robin-thompson
3 weeks ago
1,035 posts

Matt Berg wrote, in partI may seem pedantic when referring to parts of an instrument, but really, I would like to our instrument take its rightful place as an American treasure.

@matt-berg I share your desire to see our instrument take its rightful place.  And I don't see your approach as pedantic at all.  




--
Robin T
one of the Moderators here :)
Keep a song in your heart!
Matt Berg
Matt Berg
@matt-berg
3 weeks ago
56 posts

Most of us know the story of how Jean Ritchie and the 20th Century revival saved the dulcimer from the dustbin of history.

When starting to build dulcimers, I joined a different online group to share ideas.  Using the word dulcimer was like kryptonite, no responses, no comments.  I get the same reaction bringing my dulcimer to many jams,..., "oh, now we are limited", "can you play our songs".  I have also noted the lack of young people at our festivals.

Soon, we will need a 21st Century Jean Ritchie to save our instrument.

Much of this is self inflicted.  Only a few musicians play music from the last 25 years.  And many dulcimer builders insist on using terms that make them sound like they do not understand acoustic instruments.

I may seem pedantic when referring to parts of an instrument, but really, I would like to our instrument take its rightful place as an American treasure.

Sam
Sam
@sam
3 weeks ago
171 posts

I'm seeing some fingerboards stop slightly south of the last fret and a saddle or bridge like that of a violin actually afixed to the body of the dulcimer. Matter of fact, I have come to believe that only imagination limits the styles and or structure of our beloved instruments ... and that's ok. If we accrue knowledge of the instrument and it's many variations, we will pick up sufficient terminology to understand what most folks are talking about. If we don't understand, I've yet to see a builder or musician that would not take a moment to explain. 




--
The Dulcimer. If you want to preserve it, jam it!
John Gribble
John Gribble
@john-gribble
3 weeks ago
94 posts

I guess I'll have to install some braces to my banjo head so I can properly call that little wooden thingie the strings sit on a bridge. Here I've been wrong for almost 60 years! And my violin, too! Oh, drat! giggle

IRENE
IRENE
@irene
3 weeks ago
154 posts

I LOVED THIS DISCUSSION.....makes my mother's day happy.  Skip, Now I have a new name for that whatjajigger at the top and that thingamajig....great name for the bridge.  yep, I look at sites that have "walkabout dulicmers".   very beautiful instruments, but they are not dulcimers.   BUT then we could end up talking story ALL NIGHT about what is and what is not a dulcimer or dulcimore.......modern or traditional....Southern or Western....or just throw an apple at ya.  Thanks for all your comments and I learn a whole lot from ya all.   aloha, irene

Skip
Skip
@skip
3 weeks ago
251 posts

I guess y'all are discussin' that percission  string support thingamajig. You know, the one on one other end from the string tightener doohickys. Back here in the hills, we call 'em the back string lifter and the one by the string tighteners is the front string lifter.  poke   

Don't suppose it really matters much what they're called as long as both folks doin' the discussin' are talkin' about the same part. gringrin

Dusty Turtle
Dusty Turtle
@dusty-turtle
3 weeks ago
1,255 posts

I think there are two points of confusion here.  One is that dulcimers and guitars have traditionally had different construction. Whereas guitars clearly have both a bridge and a saddle, dulcimers sometimes have a saddle inserted directly in (or on, if it is floating) the extension of the fingerboard, and sometimes there is a single wooden piece (which may or may not be braced) with a broad bottom and a much narrower top, functioning as both a bridge and a saddle.  And recently many dulcimer luthiers have indeed been opting for guitar-type construction with a clear bridge and saddle.  Because of this variation, many people, myself included, almost never use the term "saddle" and just refer to the bridge regardless of whether we are referring to the part attached to the soundboard or the part with grooves through which the strings lay.  But I've been corrected by more than a few professional luthiers when I've used the term "bridge" instead of the more precise "saddle." 

As long as they understand what VSL I want and how far apart I want the strings, they can call it bubble gum and I don't care.sun




--
Dusty T., Northern California
Site Moderator

As a musician, you have to keep one foot back in the past and one foot forward into the future.
-- Dizzy Gillespie

updated by @dusty-turtle: 05/09/20 06:34:41PM
Ken Hulme
Ken Hulme
@ken-hulme
3 weeks ago
1,736 posts

OK.  I'm wrong.  40+ years of being a dulcimer person and not carrying about other instruments. 

Still doesn't change the fact that the dulcimer world calls the thing with notches the Bridge, and the distance between the nut and bridge the VSL not the 'scale'. 

Dulcimers are NOT guitars and should be discussed in dulcimer terms not guitar or lute or piano terms.

Matt Berg
Matt Berg
@matt-berg
3 weeks ago
56 posts

Wikipedia is an excellent starting point for researching a subject.  However, this quote is taken directly from the Wikipedia page on Wikipedia:

 

Wikipedia does not consider itself to be a reliable source   . Many academics distrust Wikipedia   [23]    but may see it as a valuable jumping off point for research, with many of the reliable sources used in its articles generally seen as legitimate sources for more in-depth information and use in assigned papers. For this reason some academics suggest ‘Verifiability by respected sources’ as an indicator for assessing the quality of Wikipedia articles at the higher education level.   [24]

 

And just for the record, in its early days I submitted two short articles to Wikipedia that were published and I regularly donate to Wikipedia.

Corvus
Corvus
@corvus
3 weeks ago
8 posts

Matt is totally correct with his definition of the 2 words bridge and saddle. Close to all dulcimers have a saddle. A saddle is a separate bearing surface and it is inserted into  a bridge (on mandolins, guitars etc). Hardly any dulcimers have a bridge, so the saddle is instead inserted into a groove on top of the dulcimers fret board just behind the strum hollow, or sometimes it just rests on the top and is moveable for intonation purposes. A tiny minority of dulcimers have a bridge that runs at a 90 degree angle to the fretboard; this bridge is usually glued directly onto to the soundboard, and a saddle is inserted into the top of the bridge.  Either way, the strings are positioned on top of the saddle. They are the facts and virtually 99.99999% of luthiers worldwide are aware of the correct definitions.

The vibrations go from the strings directly into the saddle, then into the bridge below or in the case of dulcimers into the fret board below, they are then transmitted into the soundboard, sides and back.


updated by @corvus: 05/09/20 11:54:43AM
Ken Hulme
Ken Hulme
@ken-hulme
3 weeks ago
1,736 posts

I have a minor quibble with Matt Berg's definition of Bridge and Saddle.  From the Wikipedia Bridge (Instrument) discussion:
bridge  is a device that supports the  strings  on a  stringed musical instrument  and transmits the  vibration  of those strings to another structural component of the instrument—typically a  soundboard , such as the top of a guitar or violin—which transfers the  sound to the surrounding air....  Bridges may consist of a single piece of material, most commonly wood for violins and acoustic guitars, that fits between the strings and the resonant surface. Alternatively, a bridge may consist of multiple parts. One common form is a bridge with a separate bearing surface, called a  saddle    
So, the Bridge is a vertical bit which holds the string up.  Dulcimers only have a Bridge.  Guitars and such have a vertical piece called a Bridge and a baseplate called a Saddle.  

Anchor location matters.  Remember that dulcimers do not produce their sound the way guitars do.  On guitars the top is so important to the creation of sound that it is called the soundboard.  On the dulcimer, the top is a minor aspect of sound creation because it is so small an area, and it is blocked from transmitting vibration by the massive longitudinal brace we call the fretboard.  As mentioned, most dulcimers anchor the strings away from the soundboard/top.  Most guitars anchor the strings on the Saddle which is attached to the soundboard.  Strings anchored on the soundboard must supply some vibration directly to the top.  Strings anchored off the top can only transmit vibration to the top via the bridge

 

Matt Berg
Matt Berg
@matt-berg
3 weeks ago
56 posts

Mounting on the soundboard produces more over and undertones.  Mounting across the soundboard produces fewer.  If you are ever in a session with a Gallier, you can hear a clear difference.

Skip
Skip
@skip
3 weeks ago
251 posts

Here's a few confusion factors just for fun;

Consider that pressing a string on a fret creates a new VSL, so fretting at the 7th [or other] fret leaves an unplucked portion of the starting VSL. Sympathetic/mechanical vibration could cause buzzing or unwanted [harmonic] overtones on the unplucked portion. 

The ends of the string on each side of the designated/primary VSL form a sub-VSL and can be considered to produce a harmonic of the primary VSL.

The radii of the stop points are not being specified [just assumed] in association with the string properties, .020" R vs 2' R, one pretty sharp, one almost flat on an 1/8" bridge for example.

Etc. Etc. [Theory vs practicality vs experience vs opinion vs???]

Without precise conditions and measurements?????

What I hear [not very good] or do vs what someone else hears or does ends up being pretty subjective. My $95 kit sounded just as good to me as a classmates $500 custom MD.

Most all of it seems to work just fine.

pokesmile

NateBuildsToys
NateBuildsToys
@natebuildstoys
3 weeks ago
19 posts
Yes, a zero fret seems to me to be an easy way to ensure a nice radius to your nut.

Interesting I have always just used the term bridge i guess because the book i learned from (which is not a credible book) says it.

I would say though that where the strings are anchored should only matter if you assume that the portion of string length outside the VSL matters, which seems like it may not be the case. I would wonder mechanistically how it is that where the string is mounted affects anything and what it may affect?
Matt Berg
Matt Berg
@matt-berg
3 weeks ago
56 posts

And speaking of controversial, if you are comparing dulcimers to guitars, it helps to use proper luthier terms.  Technically, very few dulcimers have a "bridge".  A bridge bridges the internal bracing.  As most dulcimers either lack internal bracing or lack anything that spans them, most dulcimers do not have a true bridge. What dulcimer builder call a bridge, every other luthier calls a saddle.  However, as to part of your question.

Most guitars have the strings anchored to the soundboard.  Some dulcimers, Gallier in particular, anchor their strings in the same way.  The vast majority of dulcimers anchor their strings to the edge of the soundbox.  Comparing the string angle on a instrument with the strings anchored to the soundboard to one with the strings anchored to the soundbox is an apple to oranges comparison that will get you nowhere.

Jazz guitars anchor their strings to the edge of the sound box.  I read an article in American Lutherie in which the author tried various string angles to see which was best.  The author decided that a more shallow string angle led to a louder more jangly sound.  As the angle sharpened, the sound became clearer.  Beyond 15 degrees, the angle noticeably reduced the volume.  The author concluded that 15 degrees was the optimal angle.

As noted above guitars are not dulcimers and dulcimers are not guitars.  I build my instruments with the 15 degree angle at the saddle (bridge).  I like the sound, but sound is musician's choice.

For the headstock, I also use the 15 degree angle.  I have no particular reason for doing so other than it works for me.

And just for full disclosure, my dulcimers do use internal bracing, a true bridge and a floating fretboard.  So take anything I say with a grain of salt.  The attached picture is of a build I intend to finish this weekend.

IMG_20200508_080638.jpg

Ken Hulme
Ken Hulme
@ken-hulme
3 weeks ago
1,736 posts

IIRC lutes have such steep angled heads because the strings are gut, not metal, and that supposedly aids in keeping the string in tune.  

The string break angle that I learned from my building mentor was 14 degrees.  Where these numbers come from is a mystery.  

Your observations on rounded vs angled string breaks, particularly at the nut end are very interesting and validate the Zero Fret with a string guide as perhaps a better way to create the VSL. 

NateBuildsToys
NateBuildsToys
@natebuildstoys
3 weeks ago
19 posts

This might end up being a controversial topic, since I cant seem to find a lot of agreement on it elsewhere, but I'd like to know what y'all know and have observed about how much the headstock angle, length of the headstock, radius of the nut, and bridge breakpoint angle, radius of the bridge, and excess of string between the bridge and tailpins affect tone, volume, and sustain.

My research has indicated to me that people just dont agree for the most part on these questions. The highly credible @Ken-Hulme said in a forum post *"Position of bridge relative to the string pins or break over the end (how much string is aft of the bridge) affects sustain"* Lutes have an extremely sharp headstock angle, apparently due to the desire to ensure that the strings have a rigid boundary to their VSL. Brian May's Red Special has such a subtle headstock angle it almost appears that the string is not bent over the nut at all. One local luthier has personally told me that a 10 degree headstock angle is necessary to ensure that the string is held in place and anything past that is just builders preference. Gibson has some guitars with infamously sharp headstock angles, which their website claims improves tone. My friend Allen took a board and stretched several strings across it at different angles, and told me that a 6 degree angle was the lowest he could avoid buzzing at. (interestingly I looked at my acoustic guitars and noticed both of them have a <10 degree angle that they stretch over the bridge at) He is much stronger than me at physics, so I'm inclined to believe his explanation that you need enough downward force on the VSL boundary to be greater than any upward force from the string's vibration, and any additional force past that is redundant. Makes sense to me since that's the case with fretting; you only need just enough pressure to keep the string in contact with the fret, adding more pressure past that does not give extra sustain, tone, or volume, so why would the bridge and nut be different?

One key difference that has come up in my own experiments is that in the past I often cut my nut and bridge at a straight angle (whereas frets are obviously rounded on their tops) and noticed buzzes, and abnormally quiet sound. It was explained to me that I should not expect a steel string to bend at an angle, rather at a radius.  When I went back and cut new bridges with a radius past the break point the difference was night and day in terms of increased volume and resolving buzzing issues. In the attached image the black objects represent 'bridges' the red lines represent 'strings'. The first diagram shows a 'bridge' with very minimal contact, which I believe puts tremendous amounts of extra stress on the bridge and the string. The second shows better contact but still a sharp angle at the breakpoint, which i believe can cause intonation issues and buzzing since the string might not actually be able to bend all the way to match the angle of the bridge without over-applying string tension, and therefore the breakpoint may be further back on the bridge than intended. The third diagram is what I currently do more or less, which is round off the side of the bridge and nut that is outside the VSL so that the string has a lot of contact and no sharp angles. I have never paid attention to the length of string outside the VSL, I have always assumed that if you have adequate downward force on the bridge and nut, that anything past them is irrelevant. A lot to think about but I'm sure plenty of you have thought about these things before! I'd love some more perspective

Tensions.png
Tensions.png  •  24KB


updated by @natebuildstoys: 05/10/20 02:34:31PM