Double Bass tailpieces violin style vs...

[luisraulmunoz]

I wonder what if any consensus there is regarding the main types of tailpieces for bass, those that show the cable in the front (dont know how to refer to them) and the violin style tailpiece with the holes underneath. How does the effect of the tension on the bridge/belly differ between these two types?


I have been having problems with my bass which suffers from excessive tension, and at times can become very hard to play (requires more strenght to initiate notes etc.)
I had a rather cheap tailpiece (doesnt seem like real ebony the wood is dyed black) with the cable showing in the front attached with some rather stiff metal wire.
Now I wanted to change the tailpiece because I always figured that the violin style seems better since the cord is attached in a straight line to the tailipiece without diverting any force downward (i am sure this assumption will generate some debate). Now I am not a physicist or luthier but seems obvious to me that the simpler the structural design the better it tends to function in string instruments.

So I decided to change the tailpiece, bought an inexpensive but nice rosewood tailpiece from Dov schmidt and some of the kevlar tailgut to go with it.
After the change the bass seems to resonate better and the response has become easier, the difference is clear. The how or why, I can speculate but is not as clear but I am sure that the instrument is easier to play and is more open.
aside from the change in tailpiece (the new tailpiece is a bit larger with more mass and density in the wood), tailgut (heavy wire vs. kevlar cord) the only other difference is the fact that the string length from bridge to tailpiece is a bit longer than before though this was not planned, just the tailgut was not as long as the wire it replaced.

So I would love to know any insight that might be offered as to how such a simple change can have such a noticeable positive effect.

Regards,

Luis

 

[Jake deVilliers]

You changed quite a few parameters there, so I'd be very reluctant to attribute a change in sound to just one of them. You changed the tuning of the after-lengths, the flexibility of the tailpiece assembly and by altering the mass you changed the resonant frequency of the tailpiece as well - the location of the tailgut holes hardly even comes into it.

If you want to see what kind of change the holes would make, you'll need to quantify the current setup and then drill holes through the tailpiece and fasten it to the bass that way, with the after-lengths tuned exactly the same. Then you can draw an accurate conclusion. In my experience, the location of the tailgut only changes the angle that the tailpiece rides at, nothing more.

 

[luisraulmunoz]

Thank you for your comment Jake. I agree with you, there were too many parameters to attribute it to just that.
But even though these parameters (in my non professional experience) would affect resonance and openness still its the "perceived" (yet very clear to me as a player) change in ease of response/initiation which I (right or wrong) attribute to a reduction in tension on the top of the instrument.

Still I think that one of the two designs has to be better than the other or at least that they must be dealing with the tensile forces in different ways and to different effects, just because the violin style design seems to deal with the tension in more of a straight line as opposed to the other design (does it have a name?) which by wrapping itself around the top of the tailpiece to be secured suggests to me that it might also create some degree of downward force on the tailpiece which could then be transferred to the bridge as well. Its just my intuition speaking, I havent studied physics in quite a while...so the question on that specific point is one that would merit being isolated on purely theoretical grounds. The way I see it, either my observation can be easily disproved from the point of view of physics or there is something to it...Im hoping to find some perspectives...

Though I must point out that the former tailpiece was really crappy now that I look at it again and that metal cord looks very stiff compared to the kevlar cord...

 

[tstone]

Changing the way the tailgut attaches to the tailpiece does not change the string tension, the break angle of the strings over the bridge, or the downforce on the bridge.

I'm not saying you didn't hear a beneficial effect from the changes you made, but those three factors were not responsible.

 

[luisraulmunoz]

Thank you for your reply. Could you elaborate or provide some reference? I would appreciate it.

I agree about the string tension and the angle over the bridge, but I dont agree about downward pressure on the bridge, now the difference may not be great but I believe it does change because of the way the force is distributed. Im trying to find some reference on the subject but my knowledge of physics is well limited and have little time as I am trying to prepare an audition...I keep on searching for some reference.

However if I observe that the rest of the string instruments seem to have settled on using the hidden tailgut tailpiece type, as far as I know that type of tailpiece has been adopted for almost all modern violin/cellos. Baroque instruments on the contrary use the front showing tailgut tailpiece type as well as low tension strings...

Now my argument is not that one type is better than the other but to determine whether there is any difference in sonority by changing just this one factor. Unfortunately Im reluctant to drill holes in this tailpiece in order to test the theory at this moment but maybe if I get a cheap tailpiece in the future I could experiment then doing an A/B comparison.

 

[tstone]

I agree about the string tension and the angle over the bridge, but I dont agree about downward pressure on the bridge...

The tailpiece is basically what is called a two-force member in Statics (a branch of Physics). In such a member, the two forces must be equal and colinear. So the strings are aimed directly at the break point where the tailgut wires break over the saddle. That's true regardless of how the tailgut wire is terminated on the tailpiece.

Same string tension, same break angle over bridge = same downforce on bridge.