Tuesday, August 16, 2011

CAMBER: THE HEART OF A BOW

As far as the way a bow performs and sounds there three things that represent the bow maker’s intentions and what he or she strives to achieve for a player and their instrument. They are the choice of wood, the graduations of the stick and the camber or curve of that stick. Two of those things are immutable. Certainly the choice of wood is fixed and it is highly unlikely the graduations will be changed although it would be possible to plane down a stick further.

But the camber or curve of the stick is put in place with heat and sensitive bending. If the stick is heated up again it is easy to change this curve. This puts every bow at risk if it falls into the hands of a repair person with a lack of respect for the maker’s intent and the belief they can ‘improve’ it according to their own theory of bow design. This type of individual is rarely capable of actually making bows, much less making them to an exacting player’s requirements. In addition an original camber is an even curve from one end of the stick to the other. To truly re-camber a bow would entail many hours of painstakingly correcting the curve every inch of the way while assuring that it stays straight; a very difficult task. So the repair person typically heats that bow up in a couple of spots and adds camber there resulting in ‘hard’ spots in the curve. In a few minutes the original maker’s concept for this bow is changed forever. To put it in perspective, in over 30 years of making and working with bows, I have never found it necessary to change another maker’s camber.

During the course of the 19th century in Paris where most of the bow’s evolution occurred, the way a bow was cambered evolved significantly and the way the stick was tapered or graduated evolved in a parallel course that complimented the changes in camber. Starting with Tourte the stick tapered quite evenly from frog to head and the camber was moderate especially towards the tip, which gave the stick flexibility there. This concept evolved slightly as the Peccatte school in the mid 19th century made the stick somewhat finer at the tip and added some camber to compensate. In the later half of the century Voirin’s ideas became more and more influential. Voirin believed that the bow should be as light as possible without losing stiffness and to achieve this he completely redesigned the bow. Voirin’s new bow had a lower frog and head, which put the hair under more tension. The stick started very fine at the frog and swelled out to maximum diameter just past the grip and maintained this large diameter past the middle. Then it tapered rapidly until it was exceptionally fine behind the head. To compensate for these graduations, the stick was relatively straight from the frog to the middle and then took a strong curve, which kept increasing up to the head. The Voirin bow when tightened stayed relatively stiff towards the head with a pronounced hook in the curve even when under tension. Voirin’s concept was adopted by Lamy, Sartory and the other makers working into the 20th century. These bows were exceptional off the string, with a bounce point relatively close to the frog, and suited the taste of the times admirably. At this time the idea that the perfect camber manifested plenty of curve at the tip was fixed.

Although the Voirin school of bow making enjoyed a great success, many of the finest players continued to use early 19th century sticks as they do up to this day. Bows by Tourte, Eury, Peccatte and their contemporaries continued to be highly valued because of their phenomenal sound potential and nuance. For this reason makers in the renaissance of bow making that began with Bernard Ouchard’s students in the early 80’s have usually chosen the earlier 19th century style. Nonetheless there persists a bias in favor of a decent amount of camber behind the head and relatively few makers actually use Tourte’s relatively flat camber despite its potential. But one thing is certain, the graduations and the camber of the best bow makers are always matched so the bow performs properly.

Not long ago a client of mine, the concertmaster of a major orchestra brought his bow back for a check. He had been breaking some hair. One look sufficed to see that the bow had been recambered, and recambered poorly. He told me that a bow repairer who worked for a well-known shop had convinced him the bow would be improved greatly if he could ‘adjust’ the camber. This consisted of adding some ‘Sartory’ style camber to the stick behind the head and in the meantime the bow was warped to the side. I was very thankful to have had an opportunity to restore the camber and my client was relieved to have his original bow back. This stick, a remarkable piece of wood and graduated in the spirit of the early 19th century was completely unmatched to Sartory’s type of camber. It is very important that players be aware of the risks involved in having adjustments made. There are very few bow restorers with the sophistication and understanding to make these adjustments. If the maker is still living the conscientious and knowledgeable restorer will recommend sending the bow back to the maker.

Bow are made of living material that is sensitive to humidity and other factors. Bows will occasionally warp somewhat in time, turning to the left or right or losing a bit of camber. A little loss of straightness is not necessarily a problem if the player is accustomed to the bow and it is also far better to have less camber than too much camber. If a bow feels good in the hand a player is not obliged to have corrections made. In general violin bows that turn slightly to the right and cello bows that turn slightly to the left actually compensate for the sideways force that occurs when the bow hair is inclined to the side. But if something must be done to correct the camber it is of great importance that the player entrust this correction to an expert. In the case of an early bow it is important the restorer be familiar with the cambering practices of the maker whether it be Peccatte or Sartory. Before making any corrections the restorer should trace a record of the existing camber so it can be recreated if need be.

A bow can be of use for 200 years or more and the owner of a fine bow is the guardian of that bow for future generations who may use it. The majority of damage to bows occurs during re-hair when all the delicate parts are exposed. But it is difficult to locate the best people to work on one’s bow. Even major shops have difficulty securing the best people because bow makers tend to be independent and establish their own shops. Many of the best restorers like David Orlin of Ann Arbor work in the peace of a smaller town and have all their work delivered by Fedex. Locating a member of the American Federation of Violin and Bow-makers is a good start for there are rigorous requirements for membership. However this is not a guarantee and some experts like Isaac Salchow or Christopher Dickson are not members. Players should definitely be open to sending their bow away if there is a lack of competent work in their area. The value of their investment is at stake not to mention an essential tool. There are also times when a player’s situation evolves and the bow that has been their standby is no longer quite appropriate. A player’s new violin may require a somewhat different stick or a different playing environment may change things. The client I mentioned earlier found that he was playing more aggressively after his appointment as concertmaster. It is important to understand that a bow is what it is and no adjustments to camber will make it something else. Violins can be adjusted quite significantly with different bridges, sound posts, strings and so on but it is far better to consider another bow than to think about changing an existing one.