Fingerboard and Bridge relationships

[Ken McKay]

Did your fingerboard ever love your bridge? Is your bridge plotting adultery? Was this an arranged wedding, a shotgun perhaps?

NO, this is serious! Have a look at the photos. The first shows the fingerboard and bridge and their bow clearance shaped like in the Strobel Useful Measurements book. This basically sucks. The middle strings are way higher off the fingerboard when the "classical bridge shape is used, and still high when shaved down flatter for "jazz". The second Photo is with a beefier fingerboard that is shaped to give more height under the middle strings, yet preserving the bow clearance with a matching bridge.

I call it a parabolic fingerboard and bridge and it works well on a real instrument. The only catch is that the standard fingerboard blanks are a too shallow to achieve this. I had to start from a plank of ebony.

[Matthew Tucker]

I know exactly what you mean ... but I'm wondering how the parabolic FB works for fast string crossings and double stops in TP?

Also - this shape looks OK for double stops on D and G and E and A, but it looks like bowing G or E alone will need either a much higher bridge OR thinner C bouts.

[robobass]

Ken,
I'm behind the parabolic idea, but that drawing seems a bit extreme. I've seen some basses of Karr students which had a strong parabolic shape - similar to your second drawing. I found it uncomfortable because I had to raise and lower my arm so much to make string crossings (not to mention C-bout clearance issues). I see the advantage of reduced hitting of adjacent strings, so I imagine it is attractive to many classical players, but I prefer less overall arch.

Below is a drawing of the end of the FB of my Geiger, which was recently dressed to order for a mix of jazz and arco. It is slightly parabolic. I laid the template I made from the Geiger onto my Pfretzchner, which was dressed only for arco and on a different continent, and found that the curve and height relation (the strings of course a bit higher) were almost identical. I don't know anything about the Stroebel book, but suspect that few modern bass guys are following it to the letter, if that is what it recommends.

I've always tried to cultivate an arco technique which maximizes the sideways movement of the string. I want to keep my action low, but still make a big arco sound. The secondary benefit is that I can play a flatter (larger radius) fingerboard, and thereby reduce the arm movement needed for crossings.

In the end, I think that a parabola is exactly the right idea. How much of one will come down to the preference and playing style of the individual.

[robobass]

Originally Posted by Matthew Tucker

I know exactly what you mean ... but I'm wondering how the parabolic FB works for fast string crossings and double stops in TP?

Also - this shape looks OK for double stops on D and G and E and A, but it looks like bowing G or E alone will need either a much higher bridge OR thinner C bouts.

Matthew posted while I was writing! About the C-bouts I would say that the idea would work on some basses and not others - unless you want to get into changing the overstand and/or neck angle. String crossings will require more movement, but for some the extra work would be a worthy sacrifice for the string clearance gained. I don't think double stops would be affected much, but I do a lot of triple stops in my solo Bach work. Here, the increased clearance would be a disadvantage!

[Matthew Tucker]

Here's a tracing of a fingerboard shaped by Mario Lamarre for Maxime Bibeau. Maximum thickness 33mm. Quite a wide fingerboard, my blanks wouldn't quite do it. I notice that the G side is slightly flatter.

[Ken McKay]

Originally Posted by Matthew Tucker

I know exactly what you mean ... but I'm wondering how the parabolic FB works for fast string crossings and double stops in TP?

Also - this shape looks OK for double stops on D and G and E and A, but it looks like bowing G or E alone will need either a much higher bridge OR thinner C bouts.

Well it varies with personal preference, I think. I have not had any comments that is is a problem though. The whole set up works together and if everything feels good, then the focus goes elsewhere, like the music. So I guess it string crossing in thumb is not a problem and maybe even easier, but I am not sure.

Good point about the bow maybe hitting the edge of the C bout. That has to be worked out on paper before doing this kind of thing.

[Ken McKay]

Robobass,

Good comments! I think we are all on the same page here. Things are going to vary according the the teacher and the player's style.

A bass I am putting an extension on (capos are nice, thanks) today has a bridge and fingerboard that match fairly well but the E, A, and D strings are all about the same height off the board. The radius is tighter than the Strobel template.

Ken Smith says he likes about a 1mm increased clearance for each string.

Matthew, That Lamarre fingerboard is about identical to the parabolic in my drawing.

[Matthew Tucker]

the other thing to take into account is that the C bout is a different width depending on where you want to bow the string. Usually your best clearance is obtained bowing closer to the bridge. But sometimes you want to bow close to the end of the FB, then your clearance isn't as good.

[Ken McKay]

...and if you bow German, your bow is at a different angle than French style with an overhand grip.

[Matthew Tucker]

Hmmm ... I'm beginning to think my idea for a pocket bass-inclinometer has commercial potential!

[Ken McKay]

Only if it does something else too, like cook pancakes or wash your RV.

At the ISB convention in Kalamazoo a few years ago a guy was peddling an invention that you kept in your pocket and it helped the bass resonate better. Pocket Rocket or something like that.

[forester]

[quote=Ken McKay;7801917]Only if it does something else too,

+1

When used in combination with the vibration energized gyroscope

[Badong]

Has anyone ever tried explaining this concept to a luthier? I had the worst experience at Robertson's. Finally, Don made me draw my own template. I'm not a luthier! I just want a fingerboard that matches my bridge. Is it that difficult to understand?

[Ken McKay]

Hi Badong and welcome to the discussions on talkbass.

Don has one of the most respected shops for double bass in the country. I have never seen him around these parts though. But I will let him speak for himself.

A lot of the set up of violin family instruments is based on tradition and goes back generations. But strings and playing styles have changed, especially with regards to the double bass. In truth a parabolic shape really makes sense and is probably the ideal shape not only for bass but for violin up to cello. But tastes vary and traditions dictate many aspects.

Fingerboard ebony is expensive and in order to match the fingerboard to a bridge with a parabolic shape the fingerboard must be thick or lose the side flats on the edge which looks weird.

Did you get what you wanted, how does it play now. What style do you play?

[Badong]

It was close. I ended up selling that bass and I was researching this subject on TB because I will be getting a new fingerboard on my current bass soon.

I feel like my first bass, which was set up by David Gage got it right. It was a round fingerboard with a nice arco bridge arch but the center strings were the same ratio from the fingerboard as the outer strings (about 1mm higher from G to E). The only other one I have seen like this was a Dan Hatches set-up (the reason I sent mine to Albuquerque) but he no longer does set-up work.

All of the reasons you listed for not addressing this problem (cost of ebony, tradition, etc) are unsatisfactory IMHO. If a luthier is going to charge me $1000 for a fingerboard these issues should have been addressed at this point.

I play mainly jazz and classical styles.

[Square Bear]

it seems to me that another consideration is the shape and dimensions of the bass, in terms of protecting your corners from bow whacks.

i recently played on a bass with this general parabolic set-up the way you describe it. did not like it very much, but then again, it may have been different than what you're talking about, it just seemed to have had the same shape. to be specific, what i did not like was that string crossings felt belabored with extra motion, and there was in general a feel of a drastically different shape than i am used to and was not really interested in getting comfortable with. also, the strings were very close together, which was a bit awkward. for what it's worth, this bass was a gary karr model from upton. not for me i guess, but some people may like it.

[Ken McKay]

Badong, I agree, you should get what you want. That is for sure. I hope your new bass works out well for you.

Square Bear,
There might be some similarities to the way Gary Upton shapes his fingerboard geometry for the GC model. I am not sure, never seen it. My string spacing is a little further apart than GC I think, in my drawing. Thanks for chiming in.

[Badong]

Does anyone know where I can find templates for a parabolic fingerboard or should I just start from scratch? How about a resource for neck blanks thick enough to handle it?

[Matthew Tucker]

looks like there are a few templates already in this thread!

[Badong]

Originally Posted by Matthew Tucker

looks like there are a few templates already in this thread!

Ratio is off once printed