Tailpiece string spacing

[Marty Kasprzyk]

Do the string spacings on the tailpiece have any affect on the instrument's sound or playability characteristics?

Should the spacings be the same on the bridge and tailpiece?

[David Burgess]

1 hour ago, Marty Kasprzyk said:

Do the string spacings on the tailpiece have any affect on the instrument's sound or playability characteristics?

I think so. A quick experiment is to switch the A and D string positions at the tailpiece, and see what happens. This would change the side-to-side mobility of the bridge, which I think is important for both sound and playability.

[Melvin Goldsmith]

Yes!..I've gone back to fat thick solid gut here to hold it all fixed like Heifetz had it

 

[David Beard]

Not sure I understand. Description?

[FiddleDoug]

As an addition to that- If there is a straight vibration path from the bridge, through the string, and right towards the end pin, is it better than having a path that "bends", with the vibration having a "kink", when it changes direction from string towards the end pin?

[Marty Kasprzyk]

5 hours ago, David Beard said:

Not sure I understand. Description?

A viola player friend wants to experiment with using different tailpieces.  The string spacings on his bridge are about 13mm and he was asking if the tailpiece string spacing should also be 13mm.  

He noticed that the string spacings for tailpieces varied with some being much smaller and he was wondering if there was any effect on his viola's sound with everything else (length, weight, tailcord, wood etc.) about the tailpiece  being the same.

 

[Don Noon]

14 hours ago, David Burgess said:

I think so. A quick experiment is to switch the A and D string positions at the tailpiece, and see what happens. This would change the side-to-side mobility of the bridge, which I think is important for both sound and playability.

14 hours ago, Melvin Goldsmith said:

Yes!..I've gone back to fat thick solid gut here to hold it all fixed like Heifetz had it

These are two different modes of tailpiece vibration, with two different frequencies and effects.

The string spacing affects the lateral mode of the top end of the tailpiece (the end toward the bridge).  In violins, this mode is usually just below the playing range.  If the afterlengths are parallel from the bridge to the tailpiece, the stiffness is at a minimum; any angle between the strings will increase the stiffness, and increase the frequency up into the playing range, where the effect is undesirable.  In violas, this mode is more likely in the playing range anyway... now you have to play around with these variables to see where the mode does the least harm.

The tailgut is another spring, which affects the vertical and lateral mode of the bottom end of the tailpiece.  This mode is always in the playing range, and I prefer to keep the free gut length short (with a thick gut) to keep the mode as high and as damped as possible.  Even with this, the tailgut is usually not stiff enough to affect the frequency of the top of the tailpiece.

 

[David Burgess]

Now, I think we're talking about at least three different things. My example, involving crossing the strings between the bridge and the tailpiece was meant to illustrate creating a "cross-stay" situation between the two parts, linking the mass of the tailpiece more strongly with the transverse motion of the bridge, and reducing the bridge motion. Something similar can be accomplished by increasing the mass the tailpiece, or reducing the afterlength so the tailpiece is closer to the bridge.

Of course, few of the various possible tailpiece configurations, considering their multiple effects, produce results that are entirely independent from each other, so one is usually working with multiple variables, and it can get pretty mind-numbing.

[David Beard]

It's Melvin's response I don't understand.

[Frank Nichols]

1 hour ago, Don Noon said:

These are two different modes of tailpiece vibration, with two different frequencies and effects.

The string spacing affects the lateral mode of the top end of the tailpiece (the end toward the bridge).  In violins, this mode is usually just below the playing range.  If the afterlengths are parallel from the bridge to the tailpiece, the stiffness is at a minimum; any angle between the strings will increase the stiffness, and increase the frequency up into the playing range, where the effect is undesirable.  In violas, this mode is more likely in the playing range anyway... now you have to play around with these variables to see where the mode does the least harm.

The tailgut is another spring, which affects the vertical and lateral mode of the bottom end of the tailpiece.  This mode is always in the playing range, and I prefer to keep the free gut length short (with a thick gut) to keep the mode as high and as damped as possible.  Even with this, the tailgut is usually not stiff enough to affect the frequency of the top of the tailpiece.

 

I think my head just exploded - thank you! I assume this all applies to Cello's also.

 

[WorksAsIntended]

58 minutes ago, David Beard said:

It's Melvin's response I don't understand.

I think he refered to the tailgut. 

[Don Noon]

1 hour ago, David Burgess said:

Now, I think we're talking about at least three different things. My example, involving crossing the strings between the bridge and the tailpiece was meant to illustrate creating a "cross-stay" situation between the two parts, linking the mass of the tailpiece more strongly with the transverse motion of the bridge, and reducing the bridge motion. Something similar can be accomplished by increasing the mass the tailpiece, or reducing the afterlength so the tailpiece is closer to the bridge.

What I think of in terms of springs, masses, modes, and frequencies, you apparently think of with a different mental model.  But we're describing the same thing, basically.  I don't think the stiffness between the tailpiece and bridge is high enough (with semi-normal afterlength arrangement) to significantly affect the modes and movement of the bridge, but does affect tailpiece modes.  Crossing the afterlengths may be different; that becomes extremely stiff, and I haven't tried that.

[TimDasler]

2 hours ago, Frank Nichols said:

I think my head just exploded - thank you! I assume this all applies to Cello's also.

 

Take a look at some setups on fine cellos and you'll see that after lengths are longer. While short tailgut seems to be favored for violins, viola and cello will have more space between saddle and tailpiece. 

[David Burgess]

2 hours ago, TimDasler said:

Take a look at some setups on fine cellos and you'll see that after lengths are longer. While short tailgut seems to be favored for violins, viola and cello will have more space between saddle and tailpiece. 

Some of those cello-type setups can work pretty well for violins too. With violins, we tend to be more entrenched in a "correct" set of dimensions, than we are with violas and cellos.

More than one time, I've put a lot of time and effort into getting a fiddle to sound its best. And then the owner took it to someone else, who told them that many things were way off, and "corrected" those things, with a very bad outcome. Maybe they "fixed" a soundpost which wasn't exactly vertical, or fixed a "wrong afterlength",  or the soundpost distance behind the bridge. Then I had to go through the same process all over again, to get it back to the owner's satisfaction.

(Well, maybe not exactly the same process, depends a lot on how careful and extensive my notes were from the original process.)

[TimDasler]

On 9/2/2017 at 3:37 PM, David Burgess said:

Some of those cello-type setups can work pretty well for violins too. With violins, we tend to be more entrenched in a "correct" set of dimensions, than we are with violas and cellos.

More than one time, I've put a lot of time and effort into getting a fiddle to sound its best. And then the owner took it to someone else, who told them that many things were way off, and "corrected" those things, with a very bad outcome. Maybe they "fixed" a soundpost which wasn't exactly vertical, or fixed a "wrong afterlength",  or the soundpost distance behind the bridge. Then I had to go through the same process all over again, to get it back to the owner's satisfaction.

(Well, maybe not exactly the same process, depends a lot on how careful and extensive my notes were from the original process.)

Yeah, in terms of the narrower range of acceptable dimensions for violins, I chalk that up to a larger sample size over time (more violins and more violinists) and the fact that it is the only instrument in the family that isn't constrained by the size of the player. 

Since some instruments seem to like an atypical adjustment, though, I always measure everything whenever I do an assessment. I keep those adjustment notes whether or not I change anything, and if something goes awry later I can get things back where they were more easily. No matter how far from "correct" it is I note exact location so I can get back there if need be. If a post is well fit to an odd position I will sometimes cut a new one rather than modify the existing one just in case someone came to that unusual location by trial and error. Helps to know if it has been to a good shop before me.

[WorksAsIntended]

10 hours ago, TimDasler said:

Yeah, in terms of the narrower range of acceptable dimensions for violins, I chalk that up to a larger sample size over time (more violins and more violinists) and the fact that it is the only instrument in the family that isn't constrained by the size of the player. 

Since some instruments seem to like an atypical adjustment, though, I always measure everything whenever I do an assessment. I keep those adjustment notes whether or not I change anything, and if something goes awry later I can get things back where they were more easily. No matter how far from "correct" it is I note exact location so I can get back there if need be. If a post is well fit to an odd position I will sometimes cut a new one rather than modify the existing one just in case someone came to that unusual location by trial and error. Helps to know if it has been to a good shop before me.

I do appreciate this. I had my Gütter with great setup at a luthier that changed the soundpost position to "normal" and adjusted the post. Never sounded the same later on...