Bass Bar-verticle or not

[fiddlesurgeon]

What were you taught about this?

 

flat-top bass bar0003.jpg

The plateau spans the length of the f holes where it stays a more or less uniform 12mm height.

It is preferred over the conventional design by the maker that gave me a start in making. I'll

just say you'd be in good company.

[Fiddler45]

So what does the plateau bar do differently for the tone?

[curious1]

I want to avoid any copyright infringements, so I scanned only the bass bar part. It is attached. What were you taught about this?

 

flat-top bass bar0003.jpg

 

Anyone else use this?

I have made bars like this and bars in which the "corners" are blended in as well other types of bars. I believe it puts the most strength where the top bends the most. Which is not in the middle of the plate but approximately at the bridge.

[Davide Sora]

I want to avoid any copyright infringements, so I scanned only the bass bar part. It is attached. What were you taught about this?

 

flat-top bass bar0003.jpg

 

Anyone else use this?

 

I do, but I don't think it change a lot compared to other possible shapes.

I like the added flexibility in the upper bout area and the strongest point under the bridge.

Works very well, at least on my violin.

 

Davide

 

[Peter White]

Ok so here's more about bass bars.  I like the photo above but I have always beveled the top of the bar, the highest point is along the length of the f holes and usually comes out even with the edges of the plate if you put a straight edge across the bar. In other words about 12 mm  more or less.  Further I was taught to measure the width of the upper and lower bouts, divide in half and then by 7.  This means that the upper part of the bar is about 12 mm from the center line and the bottom part of the bass bar is 14 mm from the center line, more or less.  I no longer taper the bar but make it a consistent 5.5 to 6 mm thick the entire length of the plate.  Anybody have objections? How much weight does a typical bar add to your top plate in the white? Peter

[Fiddler45]

So what does the plateau bar do differently for the tone?

?

[Don Noon]

So what does the plateau bar do differently for the tone?

 

?

 

Nothing, apparently.

 

How much weight does a typical bar add to your top plate in the white? Peter

 

I'd say (for me) 4 grams is about average.  I have ranged from 3.5 to 5, with the heavier ones used on fiddles that I thought were too thin, and the light ones on experiments in light weight.  Curtin's article showed Cremonese bars (probably actually replacements) ranging from 4 to 4.5 grams.

[Davide Sora]

So what does the plateau bar do differently for the tone?

 

Very hard to appreciate a difference, too many variables in play for a reliable testing.

For me it is simply a more logical distribution of mass and stiffness.

I have the feeling that enhances the depth of the low register (G string in particular) but honestly I'm not sure that can be attributed to the bassbar shape.......

 

Davide

[Davide Sora]

Ok so here's more about bass bars.  I like the photo above but I have always beveled the top of the bar, the highest point is along the length of the f holes and usually comes out even with the edges of the plate if you put a straight edge across the bar. In other words about 12 mm  more or less. 

 

I do not follow this rule, high archings requires lower bars and low archings higer ones, so I think it is misleading

 

Further I was taught to measure the width of the upper and lower bouts, divide in half and then by 7.  This means that the upper part of the bar is about 12 mm from the center line and the bottom part of the bass bar is 14 mm from the center line, more or less.

 

This is for set  the tilt only and not to determine the position of the bassbar, that is set by the bridge.

 

  I no longer taper the bar but make it a consistent 5.5 to 6 mm thick the entire length of the plate.

 

I glue the bassbar this way and put some taper afterwards, because I like full thickness bar ends.

 

  Anybody have objections? How much weight does a typical bar add to your top plate in the white? Peter

 

Regarding bassbar weight I'm with Don Noon, about 4 gr average ranging from 3,5 to 5 gr

 

Davide

[Peter K-G]

I tune the top's M5 back to it's original frequency (no bassbar and without f-holes) by adjusting the bass bar. they end up 10-11 mm high, measured towards the middle.

 

 

 

[curious1]

This is about typical for me.

[Melvin Goldsmith]

Imagine  lines across the widest parts of the upper and lower bouts of the front. I try to have my bar at near 90 degrees to the belly where it passes in these places. I also put the highest part ahead of the bridge....pic below is all I could find in a copy of 23mm high Belly Goffriller viola. (The high arch makes it an example to be taken in context)

[curious1]

This is about typical for me.

image.jpg

Basically like Joe Curtin's article in The Strad a few years ago. The heights of the bar follow a linear regression.

[Peter K-G]

This is about typical for me.

image.jpg

 

 

Imagine  lines across the widest parts of the upper and lower bouts of the front. I try to have my bar at near 90 degrees to the belly where it passes in these places. I also put the highest part ahead of the bridge....pic below is all I could find in a copy of 23mm high Belly Goffriller viola. (The high arch makes it an example to be taken in context)

 

How dens wood do you use for those bass bars? they look heavy, over 5 g? Mine is typically ~0,45 g/cm3 and high ringing (speed of sound) around 3-4 g.

[curious1]

How dens wood do you use for those bass bars? they look heavy, over 5 g? Mine is typically ~0,45 g/cm3 and high ringing (speed of sound) around 3-4 g.

That bar is .38g/cm3 (low for me) and 5800m/sec (avg for me). 12mm tall and 3gms.

[Craig Tucker]

This is about typical for me.

image.jpg

 

Curious 1,

 

Nice bar.

Mine look much like this now-a-days.

[JohnCockburn]

That bar is .38g/cm3 (low for me) and 5800m/sec (avg for me). 12mm tall and 3gms.

Hi C1.

It looks quite a bit higher than 12 mm in the photo. Which side is this measured from?

Also, would it be possible to outline the "curtin method" for those of us who don't have the article?

Cheers

John

[curious1]

Hi C1.

It looks quite a bit higher than 12 mm in the photo. Which side is this measured from?

Also, would it be possible to outline the "curtin method" for those of us who don't have the article?

Cheers

John

12mm measured from the inside of the bar. I remeasured just to be sure. Curtin's method is based on a triangle. I think Carl does a similar thing but with the high point in the middle. I'll write later with a better description.

[Peter K-G]

Curious 1,

 

Nice bar.

Mine look much like this now-a-days.

 

It very elegant yes, I use to make them like that, but now I do them like this:

 

[Melvin Goldsmith]

How dens wood do you use for those bass bars? they look heavy, over 5 g? Mine is typically ~0,45 g/cm3 and high ringing (speed of sound) around 3-4 g.

Hi Peter,It's a good question.

My bar is from a front bought from Pahler dated 1969. The density is 0.42. The bar itself is not actually heavy. I use a much thinner basic profile than I see on your nice photos on post 35 in this thread. I'll add a picture to illustrate. I am aiming for lightness and stiffness in the bar generally so I try to shape the proportions in favor of height rather than width. I'll generally use higher density wood for the bar even if the belly is low density...but It's worked for me with low density bars also. 

 

EDIT

The caption to the drawing should read      ' bar profile at highest point'

[Peter K-G]

So the weight is pretty much the same (3-4 gms) with both design. The main reason why I have change the bass bar style is to spread the load/movement  over a longer area:

 

http://www.zuger.se/Improving_the_dynamic.html

 

(and it's easier to tune )

[nathan slobodkin]

Hi Peter,It's a good question.

My bar is from a front bought from Pahler dated 1969. The density is 0.42. The bar itself is not actually heavy. I use a much thinner basic profile than I see on your nice photos on post 35 in this thread. I'll add a picture to illustrate. I am aiming for lightness and stiffness in the bar generally so I try to shape the proportions in favor of height rather than width. I'll generally use higher density wood for the bar even if the belly is low density...but It's worked for me with low density bars also. 

 

EDIT

The caption to the drawing should read      ' bar profile at highest point'

Melvin 

May I ask what led you to favoring lighter bars over heavier? My intuition is that a lighter bar will favor response while a heavier bar will increase the depth of the bass. I'm being partly influenced by the comments concerning the Verzi double bar system which enjoyed a brief popularity in the 1920s and supposedly gave a deeper tone to the violins it was installed on. In any case I started shaping my cello bars without tapering  in order to add weight in the center and I think it gives a boomier bass which players seem to like. I generally like darker sound on violins also but am not sure I can hear any difference from different bar shapes. I haven't actually tried different bars on the same instrument but since I make only a few models and stick with the same wood for a number of instruments I usually can get an idea of what effect my experiments have.  

[Melvin Goldsmith]

Melvin 

May I ask what led you to favoring lighter bars over heavier? My intuition is that a lighter bar will favor response while a heavier bar will increase the depth of the bass. I'm being partly influenced by the comments concerning the Verzi double bar system which enjoyed a brief popularity in the 1920s and supposedly gave a deeper tone to the violins it was installed on. In any case I started shaping my cello bars without tapering  in order to add weight in the center and I think it gives a boomier bass which players seem to like. I generally like darker sound on violins also but am not sure I can hear any difference from different bar shapes. I haven't actually tried different bars on the same instrument but since I make only a few models and stick with the same wood for a number of instruments I usually can get an idea of what effect my experiments have.  

Hi Nathan,

That's food for thought because from what you say it would seem we are seek a similar bass sound although I also ideally seek fast response as I guess you do too. Whilst I seek to make a bar light I still want it strong and mine are on the deeper side. I'll try a heavier bar next time the chance arises and see what happens. 

I can share one experience of violins with bars that were very heavy in the center....Many years back I finished some fiddles off for a friend who'd had them made in the white in Italy. The bars were unusually deep and heavy in the middle ( about 16mm high and I was asked to leave them as they were) Most of the fiddles had problems like incorrectly shaped necks /boards,badly placed F holes ill fitting seams etc but they all sounded annoyingly good. The bass was variable between OK and great but the E string always divine!

I have tried different bars on the same instrument a few times but I'm not sure that I reached conclusions so far other than kidding myself but I am very interested in your findings and I don't doubt them at all. Respect and thanks for sharing,

M

[Michael_Molnar]

Given that the height of the bass bar controls the ring mode E5, I imagine that going beyond the standard 12 mm peak height will produce a very high frequency response favoring the E string. The issue is to keep the weight down so as not to kill the total power output and muffle the lower frequencies. This is not a simple matter for sure.

 

Happy New Year Melvin

 

Mike

[actonern]

Is everyone measuring bar height from the same side?  Closest to the plate edge side, or closest to the centre of the fiddle side?