To answer this question, we brought in our Principal Bassist Max Kasper, who’s also a bow maker:
Short Answer: Very!
Long Answer: No two bows are exactly alike. Even those made by the same maker, and from the same woods, will be a bit different. It might help to understand this if you think of bows and instruments as works of art as well as functional things.
Baroque bows are most often made from snakewood. Modern bows are usually pernambuco. Snakewood is very stiff and much denser than pernambuco, which makes for a different sound. The design of Baroque bows is also quite different – they are shorter, lighter, and have less curve. They are also very differently balanced. Each bow will have a balance and flexibility that is all its own, which also contributes to its sound.
Each player will be looking for a bow that suits their instrument and style of playing. A friend of mine once joked that “When we buy a new bow or instrument, we never get a different sound, we just get a more expensive version of what we’re used to!”
The differences between bows are sometimes very slight, and perhaps only noticeable to the professional person who is playing the bow, but they are there nonetheless. An audience member 50 metres away may not really hear a difference between two similar bows, but the players will notice, and it will affect how we play!