Wednesday, April 29, 2020

Pernambuco Wood or Carbon Bows- Which Are Better?


By Andy Fein, Luthier at Fein Violins,
and Ivana Truong


Your bow is half of your sound.

A seemingly surprising statement, but very true.

Most professional and advanced string players have more than one bow. That's why a lot of bow cases have four bow holders! Different bows give different sounds to the same instrument and work better or worse with different styles of music. And then there's the venue. It's a good idea to have a Carbon bow for outdoor and bar gigs!

So which is better- Pernambuco or Carbon?





Here's my general conclusion about the difference between Carbon Fiber and Pernambuco wood bows- no matter what the price and supposed quality of a Carbon bow are, they all seem to have a harsh edge to the sound. They tend to bring out the higher overtones and produce a tinnier sound than Pernambuco bows do. That is, a $2,000 Carbon violin bow sounds harsher than our $400 Pernambuco Violin bow. (For the purposes of our discussion, when we refer to Pernambuco, let's qualify a minimum quality of about our Fein Pernambuco Violin Bow or its viola and cello equivalents.) And truly, I don't hear or feel any difference between a $2,000 Carbon bow and one of our $75 Carbon bows. The $2,000 Carbon bow uses fancier material for the fittings, but you can get a really nice Pernambuco bow with the same fittings for $2,000.

Pernambuco wood undeniably has a warmth that Carbon Fiber lacks, but why is that? Why does wood, and specifically Pernambuco, sound the best?

When you’re shopping for bows, almost all the “wood” bows are made from Pernambuco, a type of hardwood from Brazil. Ever since Tourte began favoring Pernambuco(1), the wood has become a standard for bows given its high density, flexibility, and beautiful red-brown color.


The center, heartwood, is what bowmakers mean when they say Pernambuco. Bows are also sometimes made from the lighter surrounding wood, which bowmakers call Brazilwood. This wood is less desirable than Pernambuco because of its lower density. We have a blog on the difference here.

The problem we're facing is that Pernambuco is on the first stage of the International Endangered Species Treat (CITES) because Pernambuco wood comes from a living tree. And Pernambuco only grows in a small area of the world. Pernambuco’s use for dye manufacture, construction, flooring, and undeniably, bow making, means that less than 7% of Atlantic forest, where the wood comes from, remains today. This has led many bow-makers and conservationists to support the International Pernambuco Conservation Initiative.


For the foreseeable future, it is and will continue to be incredibly difficult to harvest and purchase new pernambuco wood. This means that almost all new Pernambuco bows are actually made from blanks that have been cut 20 or more years ago and stored in the personal collections of different bow-makers or bow wood suppliers.


Bow blanks

https://maestronet.com/forum/index.php?/topic/340758-9-pernambuco-bow-blankswell-sorta-blanks/


As stocks of air-dried Pernambuco wood have dwindled, bowmakers and string players have explored other materials for their bow sticks. No perfect match has been found, but some other types of wood are being considered. For example, Mountain Mahogany, Ironwood, and some species of Brazilian Ipe. Andy has found Tetul wood to be a good alternative to Pernambuco fittings such as tailpieces, but not for bows.

Of course, the search for a Pernambuco alternative has also led to the rise of Carbon Fiber. For the purposes of our discussion, Carbon, Carbon Graphite, and Carbon Fiber (or the British spelling- Carbon Fibre) are all generally the same material when they are made into bow sticks. But, because Pernambuco is a living material, it's very, very hard to duplicate all of its properties with a synthetic material. 

A close-up photo shows a car spoiler made of curved carbon-fiber-reinforced polymer. It looks like a curvy black plastic material with a smooth but visible woven gray/black pattern.
A sheet of carbon fiber

https://www.teachengineering.org/lessons/view/uoh_carbonfiber_lesson01


While the affordability and durability of carbon fiber have made it a popular option for many musicians (also, way easier to travel with!), if you have ever compared a carbon fiber bow to a wood bow, you can tell that wood undeniably has a warmth that carbon fiber lacks. Nobody can say that carbon fiber provides the depth of sound that wood can. Why is that?

What we refer to as “wood” is actually a complicated mixture of different fibers, vessels (cells that transport water), rays (lines of cells perpendicular to growth rings that allow the transportation of sap), and lignins (an organic polymer that provides structural integrity to plants). That was a lot, but stay with me! Basically, wood is structurally and chemically complicated. In fact, there’s still a lot we don’t understand about how trees create wood!

Scientific curiosity aside, How does this relate to Pernambuco and wood bows? To begin with, Pernambuco has a high Young’s Modulus (ability to withstand changes in length) for its high density, which is a desirable quality for a bow. Between different pieces of Pernambuco, wood that is particularly suited for bows is characterized by higher density, more lignins, and fewer rays and vessels. The sound propagation of wood may be linked to the composition of cell walls and which cell types the wood is made out of, which can change depending on species (2).

This makes wood a very different material when compared to carbon fiber. While carbon fiber may be equally or more strong than wood in some measures, its uniformity in structure and chemistry means that while it's reliable, it can’t compare to Pernambuco's sound propagation and unique structural qualities.





Electron micrograph of carbon fiber. You can see that the structure is very uniform.

https://www.researchgate.net/publication/273407520_Interlaminar_Shear_Strength_of_Multi-walled_Carbon_Nanotube_and_Carbon_Fiber_Reinforced_Epoxy_-_Matrix_Hybrid_Composite/figures?lo=1




The 2 top images are from Pernambuco that would be ideal for bow making, you can see the vessels  (which look like holes) are smaller and there are fewer rays (which look like lines moving horizontally) when compared to lower quality Pernambuco

Images from: Pernambuco Wood (Caesalpinia Echinata) Used in the Manufacture of Bows for Stringed Instruments



Of course, there is also the expertise that goes into the selection of materials and the process of making a bow. When scientists looked at 150 sticks of Pernambuco that were categorized A-D in terms of quality for use in bow-making, the highest quality and the lowest quality woods showed significant differences, but Class A and B were similar in most properties. (3) In other words, a lot of how a bow plays and sounds also rely on the experience and knowledge of the person picking the wood.

Besides materials, there is also so much that goes into crafting a bow. A bow that is well made, correctly balanced, and comfortable to play with will probably be better for the musician and their sound than a badly made bow of slightly higher quality material. 

Fein Violin, Viola, and Cello Bows


Now you can go into your next bow buying adventure armed with a little more knowledge on the differences between Carbon Fiber and Pernambuco, and even the differences within Pernambuco wood itself.

Still, at the end of the day, you need to think about what you need personally from a bow. This blog post doesn’t mean that we think everyone should get a Pernambuco bow 100% of the time. In fact, wood bows are pretty delicate and they aren't the best for younger students and musicians who play a lot of outdoor/bar gigs. We feel that both kids and adults should learn about the scarcity of Pernambuco and take it upon themselves to be conservators of this precious natural commodity. Be honest with yourself- If you can't take that responsibility on, use a Carbon or a Carbon/Pernambuco Hybrid bow.

Recently, there have been hybrid bows, which have a Carbon-Fiber core and a Pernambuco wood veneer (Fein Hybrid Bows). We have found these to be pretty durable, a lot warmer sounding when compared to Carbon Fiber bows, and less expensive than a solid wood bow. Within the last year, these Hybrid Carbon/Pernambuco bows have become our most popular bows. with Good reason! They combine good sound, good playing characteristics, and durability. All at a lower price than our Pernambuco bows!

Remember, your bow is half your sound!




At Fein Violins, we have a large selection of Pernambuco and Carbon bows for violin, viola, and cello. Come visit us!


1. https://www.radcliffe.harvard.edu/news/radcliffe-magazine/making-bow

1 comment:

  1. .... Fabulous article ! Thanks Andy, National "Pau Brasil" day here on the 3rd. of May ! Cheers from Itamarac√°....... where extraction of "Pernambuco" started in 1503 !

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