Tonal Adjustments in Setup

[David Beard]

Wondering what people listen for to guide tonal adjustments in setup?

 

I know for myself, to a large degree I'm listening to brightness versus darkness in the tone.  And I mostly associate that with a generally more tensioned and strong setup giving harder brighter results, and lower tension tending more toward dark.

 

I know I'm trying to maximize power and response in the tone, while balancing other factors.   I want to strike a balance making brightness or darker warmth available in the tone, and a balance between openness of tone and a more reedy firmness of tone.

 

Presuming good fit of bridge feet and post, I think of tension as the first thing to adjust in the setup.  Following Gerald Botteley's advice from the Courtnall & Johnson book, I move the bridge forward to test lower tension and back to test higher tension, and see which direction gives improvement in the tone and response.

 

I try to work first from a completely standard, but somewhat beefy bridge, and a somewhat beefy and longish post a little bit closer to center line and further back behind the bridge than standard.  From this start, I try to get the tension of the instrument setup as close a possible to right, but slightly over tight, as I work the post closer toward a 'standard' position.

 

I prefer to work with bridge and post just barely thickish.  Once the tension seems close to good, but definitely not too loose, then I try to refine the post position by listening to how it affects the balance of the response in terms of bass versus treble,  and quick brightness versus slower warmth of tone.  This things I mostly test by playing in low and high positions on all strings, and by listening to how the response changes near and far from the bridge, and with different pressures and bow speeds.  

 

I try to work with the bass to treble balance first.  Mostly I adjust this by moving the post closer or further toward the center line.  Since the fit and tension/height are affected by this kind of move, I might need to make a new post to get both the tension and the bass/treble balance working well.   The nearness or distance behind the bridge foot also alters the effective tension, but less so the fit.  So I'm happy if my fiddling around with the post ends with this last dimension.  I feel like this distance most strongly effects the balance between hardness/directness versus openness/indirectness of response.  It seems very similar to moving a microphone nearer or farther from the voice.

 

After this, even though the general bass to treble balance should be good, the balance between individual strings might want some further adjusting.  I try to do this last balancing of strings by trimming away a little in the bridge cutout just below the string that wants to be a little more present and open in tone.   Once the strings seem as well balanced as possible, I consider if the tone wants more openness.  If so, I consider trimming the other cutouts of the bridge further.  But I don't want to lose strength in the bridge, so I'm least inclined to thin the bridge or post. Both these steps can lighten and open the response, but are too easily overdone.  It seems that response can get mushy and slowed, and tone thin if either post or bridge aren't solid enough.  But, response can be dampened and tone veiled if these have too much mass.

 

I prefer to end up with a very standard post and bridge in very standard positions, but results matter more.

 

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I don't think there's much out of the ordinary in what I described above.  But I'm interested in hearing more techniques people use, and the things they listen for.

 

In the part where I'm listening with different pressures and speeds and such, I do one kind of test that I haven't particularly heard discussed elsewhere.  Maybe others do this to?

 

I pay attention to how easily you can play a sul ponticello effect, and how far from the bridge you can be and still get that sound.  As well as how close to the bridge you can draw a clear brilliant tone, and where on the string you can start to get a sul tasto kind of sound.   I like it when all these colors are readily available.  I like to see the sul ponticello available out mid way to the fingerboard.  And a good sul tasto color available starting right around the fingerboard. Post to bridge nearness for example affects this greatly.  Also, I want to see similar colors available for similar contact points across all the strings, as much as possible.    More and more, I find myself using these tests as my main guide as I work through the setup.

 

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I'm hoping people will share both their process, and the special things they listen for to help judge tonal setup.

[actonern]

The problem is, you don't know if you've taken any of the parameters too far till you've gone too far.

 

For me, the result is fitting multiple posts and sometimes bridges if I'm really trying to get the best out of it.

[uncle duke]

Well Dave, if your running 12 to 16 notes all sounding good then your job is done.   Seriously,  this is a subject where I need to listen to others to learn more. 

[DGV]

I find that the weather makes a difference in the sound. I just try to get to a certain point and wait a season or two to see how the thing responds before making another pass at adjusting.

[Addie]

Personally, I think bassiness is related to post tension. E-W movement is for E-A balance. And that adjustment is pretty small.

I don't understand your comment about all strings having the same color. Each string has its own unique color--that's why we play higher positions on the A and D strings, besides fingering. Or do you mean dark-bright balance? I find the D&A brightness comes from the bridge.

[David Beard]

Hi Addie,

I wasn't very clear. I don't mean have the same color, but drawing a ponticello with similar contact point and bow stroke, or drawing a similarly brilliant and solid tone with similar closeness to bridge and stroke.

[Addie]

Ah. That would be part bridge, and part post distance from the bridge.

[Mike Spencer]

Thanks for starting this thread. I think that the tailpiece and string after length have to be taken into the equation too. Also when I make adjustments I think it takes at least overnight to settle in to hear the result, what do other folks experience?

Thanks,

Mike Spencer

[ctanzio]

I don't understand what you mean by "tension". Are you talking about the downward force of the bridge on the violin top? Or stressing the plates by jamming the sound post tightly into the violin?

 

Moving the bridge a few millimeters up towards the scroll or down towards the tailpiece will have a negligible effect on the magnitude of the force the bridge exerts into the top plate. The same hold true (to a somewhat lesser extent) by varying the bridge height. The only practical way to vary the setup load on the violin top plate is by using a different gauge string that requires higher or lower tension to reach tuned pitch.

 

The location of the bridge relative to the sound post will affect the stiffness of the top to resist the vibrations of the bridge while being played, and thus all sorts of things like loudness and timbre. Maybe this is what you are referring to?

[David Beard]

I mean most all the adjustments in a setup either increase or decrease the overall tension of the setup, which to me seems to be one of the overall most audible things, giving movement toward a harder/brighter/solid/fast/bright tone with more tension, and dark/slow/open/warm direction from less tension.  But the best overall power and response for the instrument seems to be a matter of a good 'balance' of tension for the instrument.

 

So, many things add toward a more tensioned/stronger/stiffer setup: higher post or bridge, longer string length/stop length, great string angle over bridge, stiffer/stronger/heavier wood parts(post, bridge. bar), choice of higher tension strings, etc.

 

All those things will contribute in the 'more tension' direction of a setup.  And their opposites give the other direction.

[Addie]

Haven't we been down this road before?  Raising the bridge height does not increase tension: cranking the pegs does. 

[David Beard]

Longer string length requires greater string tension to reach the same pitch.   Raising the bridge slightly nudges in this direction.

 

Increasing the string angle across the bridge increases the downward force from the string system.  Increasing bridge height strongly pushes in this direction.

 

So, a higher bridge does tend toward more tension.   Even though it is possible to raise the bridge and shorten the stop length to compensate, and raise the saddle to compensate.  If you don't make such compensations, the higher height will yield a higher tension system.

[FredN]

Has anybody did enough changes of bridge height that they have some kind of understanding what it does. In setting a fingerboard i aim for ca 160 degrees string angle over the bridge, and once tried 155, an increase in top compression, and the inst sounded a little like it had a mute on it.  The reverse, what is the result of less compression of the top by the bridge.

 

I always think we are missing an interesting parameter in describing an inst, which is the total height of the inst , say on the midline right in front of the bridge.  I would think this has some  affect on the sound of an inst.

[DGV]

I have gone from high bridge to low but not the other way around. As height decreases, power decreases and response improves.

[ctanzio]

I mean most all the adjustments in a setup either increase or decrease the overall tension of the setup...

 

From reading the rest of your responses, I would suggest that you do not have a clear grasp of what the word "tension" means in terms of physical effects.  A lot of the things you mention as changing "tension" have little to do with introducing meaningful tension into the violin.

 

For example, reasonable shifts of the sound post as might be expected during a setup are not going to add or relieve any "tension" introduced into the wood by the strings pressing on the bridge.

 

I demonstrated in some earlier posts that typical variances in bride height/string angle might yield a 4% shift in the forces at the bridge feet as a worst case.

 

String lengths might vary from a low of 324mm to a high of 330mm in a 4/4 violin setup. If you start with an average length at 327mm, then shifting the bridge a few mm either way would require less than a 2% change in the string tension in order to tune the string. And only a fraction of this change finds its way to the bridge feet.

 

Bridge height during setup is dictated by player preference for string to fingerboard clearance. If the violin was typically proportioned to modern standards during its manufacture, then the string angle over the bridge will be within a few degrees of 158. If you have a violin where this is dramatically different, then you do not have a setup issue. Something else is seriously wrong with the violin.

[martin swan]

I would disagree that minor changes in bridge height have a negligible effect! To me this is one of the most important parameters in controlling the sound of an instrument ....

I have a set of de Jacques adjustable bridges that I use for problem instruments - although they are essentially pretty rubbish bridges, they do provide guidance as to what bridge height will be optimal for a violin. And if the best bridge height requires a neck re-set, so be it.

A difference in 1mm height on the E string is clearly audible, and affects the response and tonal colour of the whole violin. After all, what is a violin if not the strings bearing down on the table. Our ears are ludicrously sensitive.

I would also disagree that high bridge = powerful and bright whereas a low bridge = dark. Lessening the tension always enhances the high frequency content.

But maybe David and I mean different things by "bright".

In exaggerated terms, a high bridge and greater down-bearing will give a stiffer response, more volume under the ear, and a concentration of energy in the midrange, often to the detriment of colour and dynamic range.

A low bridge will enhance high frequency content, give a less controlled but more radical response, generally to the detriment of the "core" sound.

My general feeling is that most bridges are higher than they should be, in attempt to get more power out of poor instruments.

 

Soundposts - I never mess much with east-west, I'm in agreement with Addie.

 

But issues of set-up are philosophically quite different for someone who owns one violin and needs to get the best out of it. 

[ctanzio]

I've never heard a tonal difference in playing an open string while lowering the height to get a desired string to fingerboard clearance. And during the initial setup, the string will be moved more than 1mm. 

 

OTOH, if a high tension E string has a rather generous clearance from the fingerboard, I have heard some fingered notes generate "interesting" timbres that disappear when the string is lowered or the string is very tightly clamped to the fingerboard with the finger. 

 

An opposite type of effect seems to occur with the G and D strings. They can have such a large vertical component to the vibration that they rattle off even a fingerboard with proper scoop. There, lifting the string by 1mm may miraculously banish the rattle.   

 

I think of these as playability issues rather than tonal fine tuning. But I've never had to deal with very old violins that may have stability issues with very thin or degraded tables. If the core timbre of a violin was affected by a 1mm change in string height, I would be concerned about its ability to generate an acceptable tone through an entire performance and changing environmental conditions.

[David Beard]

Maybe it's more truly about stop length and angle over the bridge. I tend to associate bridge height with a stronger more tensed setup, but maybe it's really the other things.

Small differences can be very important though. Consider 1mm for the post.

[martin swan]

I've never heard a tonal difference in playing an open string while lowering the height to get a desired string to fingerboard clearance. 

 

 

That doesn't surprise me - in my view, playing open strings tells us nothing of value about how a violin sounds or plays.

Perhaps when the bridge was too high, you didn't play the instrument for long enough to really know how it was performing?

But if you can't hear/feel a difference in the general tone and response of a violin with a bridge height change of 1mm, then I will never be able to persuade you that it's significant!

I would love to live in this parallel universe where the majority of violins have good neck angles, and where bridge height adjustment is purely for the sake of personalizing the action to the player. 

Are you mainly working with modern instruments?

[ctanzio]

A change of 1mm in the sound post location is not the same thing as a change of 1mm in the string length.

 

In the former case, a 1mm shift in the sound post represents a significant change in the distance between the nodal/boundary point (the sound post) and the applied force from the bridge (the treble foot and to a lesser extent the bassbar foot). If the sound post started at say 327mm from a bridge foot, then a 1mm shift is not going to do anything.

 

In the latter case, a shift of 1mm in the length of a string that is already around 327mm is a negligible tonal effect.

 

I have only setup violins made to modern standards. But even old instruments need to obey the laws of physics. One can demonstrate that small changes in bridge height cause very small changes in bridge loading, stiffness and response. That is not to say you won't encounter a violin where such a change causes some significant tonal effect. But if that does it occur, it strongly implies that there is some serious structural issue with the violin. 

[Addie]

That doesn't surprise me - in my view, playing open strings tells us nothing of value about how a violin sounds or plays.

I disagree.  I hold the violin vertically by the neck, sound holes facing away, and bow the open strings.  This tells a lot about the overall balance of the strings when setting the post.  And a post set that brings the most out of all open strings has a lot to do with how a violin sounds and plays.

[DGV]

I disagree.  I hold the violin vertically by the neck, sound holes facing away, and bow the open strings.  This tells a lot about the overall balance of the strings when setting the post.  And a post set that brings the most out of all open strings has a lot to do with how a violin sounds and plays.

 

I have a violin whose open A sounds a bit thinner than the rest.  Any idea on how to fatten it up without affecting the other strings much?  The strings are Dominant A, D, G, and Jargar medium E.

[Peter K-G]

Change to Dominant E and see what happens

[JBertholdo]

Usually E Pirastro gold works well with Dominant

[Addie]

I have a violin whose open A sounds a bit thinner than the rest.  Any idea on how to fatten it up without affecting the other strings much?  The strings are Dominant A, D, G, and Jargar medium E.

David mentioned opening up the heart under the string.  I would move the opening upwards, making less wood between the A string and the heart.  Just a little, mind you.  Also too much "Shell" at the top under the D & A can dull things down.  But try the soundpost first: move it 0.5mm towards the center.  And make sure it fits!