When it comes to his instrument, the musician is able to detect very quickly if there is a problem affecting sound or playing comfort. He will instinctively talk to his luthier about it, because he knows - it's part of his culture - that something can be done.
In contrast, the musician's relationship with his bow has an irrational element that persuades him that
everything is the result of his own technique alone. With no known alternative, he has adapted to these problems, without really
without really realizing that he's spending a lot of energy for nothing to compensate for a problem
... which in many cases comes simply from his bow.

I really enjoy taking the time to discuss when musicians bring their
bows to the workshop. I regularly observe that even some of the most prestigious bows are still played "as is" despite changes, however slight, that have occurred over time affecting the camber or straightness of the stick, causing discomfort in the playing.

However, there are clear signs that a bow needs adjustment.

- a lateral weakness in the middle of the stick, which you try to compensate for by tightening the bow more
the bow, making playing at the tip uncomfortable.
- the bow is a little too nervous and doesn't stay on the string.
- the bow has become too soft and difficult to jump, or it is difficult to find the right playing tension.
- The bow is too heavy or too light.

Once again, the musician, having no known alternative, has adapted to this discomfort and the
compensates without realizing it .

When I see a bow presenting a problem of this kind, I discuss it with the musician and his first reaction is:
"Now that you mention it, that's actually exactly what I've been feeling for years!
But how do you know? And is it possible to do anything about it?

In most cases, the answer is obviously YES.

It's possible by intervening mainly on the camber and/or straightness of the stick, on the balance of the bow and on the quality and thickness of the bit.

Unfortunately, all too often the adjustments and settings proposed by the profession are not convincing, or even counter-productive.
Bow adjustment is a very demanding operation, requiring real know-how.
As far as I'm concerned,there's an obligation to achieve results from the moment I agree to adjust a bow.

The musician taking part in a bow adjustment has the unique opportunity to feel and validate every change made to the bow.
A tuning is an opportunity to :
- explore and understand the relationship between the technical characteristics of the bow and the sensations of playing, by comparing impressions and intimate convictions with precise measurements and explanations.
- develop a vocabulary for expressing these needs.
- make the link between playing sensations and the technical characteristics of the bow being played.
- be able to define needs in terms of comfort, playing qualities and sound.
- gain valuable new information about your bow.

If all this sounds interesting to you, or if you've already experimented with an unconvincing set-up, don't be left with a bad experience,
come and knock on the right door.

In our daily work, we come across technical obstacles that are not necessarily due to our own limitations.
The fine-tuning work I did with Jean Grunberger enabled me to feel more acutely what could come from me or my bow. Adjusting the balance, the weight, the tension, a curvature at a given point on the bow is sometimes crucial to solving a problem of spiccato, sonority, detachment or projection.
Once this work was done, the musical gesture became simpler and more obvious, making my day-to-day work much easier.

Thanks to Jean, I've discovered that it's possible to tune a bow like you tune a violin!
By fine-tuning several very delicate parameters, he manages to meet the musician's exact expectations.

Working with Jean was a truly beautiful and positive experience.
He was a magician at work and could do anything I asked until we got the result I wanted with my bow.
It was a pleasure to meet Jean and his wife Claudia, who together opened up a world to me with their knowledge and art of the bow. I heartily suggest that any musician who has problems with his bow should go and see them.

As a cellist, I was familiar with the terms camber, weight, balance point, nervousness and flexibility of the bow, without understanding their mechanical meanings.
The most striking thing for me was what is known as deflection, in other words, the flexibility of the stick. I mistakenly associated powerful sound and precise attack with a rigid stick that was highly resistant to pressure.