wolf note, tailpiece position

[tartarine]

Hello everybody

I had a Kevlar tailgut on one of my cello.

 it was about in the middle of the space of the lower bout.

I put it there thinking that I was doing that  the weight of the tail piece was at its maximum.

but it made the 1/6 proportion (distance bridge-tailpiece )to the string length "wrong"

(too short 100 instead of the 115 required for the "right " proportion)

an other violin maker decided that it should be changed and put the tailpiece at the official distance 115.

now the cello has two more wolves :-)) easy to put it back as it was no problem but

I was wondering if I was right : the weight of the tail piece is at it maximum when in the equal distance bridge saddle which dampens the wolves

why does  the shorter tailgut (saddle-tailpiece distance) produce more wolves

I was wondering why it happened

Any idea ?

thank in advance

 

[Don Noon]

As I always say:  It's complicated.   Much more complicated than getting a "right" dimension or centering the tailpiece.

An instrument will have natural vibration modes, and if they are strong enough (which apparently happens more often in cellos), they can cause wolfing.  The frequencies are generally not exactly the same in every instrument.  The tailpiece, suspended on the strings and tailgut, will have natural modes as well, which vary with tailpiece weight, dimensions, string afterlength, and tailgut free length.

If the modes of the instrument and the tailpiece match exactly, the wolf note of the matching modes can be tamed somewhat.  If the modes are slightly off, it can be a lot worse.  Since all this stuff has all kinds of variables which are different for each instrument and tailpiece, you need to find out what actually works for your combination, and no prescribed settings are necessarily best.

[Marty Kasprzyk]

7 hours ago, Don Noon said:

As I always say:  It's complicated.   Much more complicated than getting a "right" dimension or centering the tailpiece.

An instrument will have natural vibration modes, and if they are strong enough (which apparently happens more often in cellos), they can cause wolfing.  The frequencies are generally not exactly the same in every instrument.  The tailpiece, suspended on the strings and tailgut, will have natural modes as well, which vary with tailpiece weight, dimensions, string afterlength, and tailgut free length.

If the modes of the instrument and the tailpiece match exactly, the wolf note of the matching modes can be tamed somewhat.  If the modes are slightly off, it can be a lot worse.  Since all this stuff has all kinds of variables which are different for each instrument and tailpiece, you need to find out what actually works for your combination, and no prescribed settings are necessarily best.

If you mess around enough with the tailpiece stuff you mentioned we might be able get it to have a resonance mode at the same frequency as a wolf note thereby taming it.

However if you have  more than one wolf note it might be very difficult to get the tailpiece to have other  resonance frequencies that also match those other wolf notes too.  So it seems reasonable to pick the worst wolf note to tame and let the others go.

This could suggest that maybe we should have a separate tailpiece for each string so we could tame up to four wolfnotes instead of just one.

[Peter K-G]

On a violin it's not too difficult to "fix" B1+ wolf