Ask Augustin 45 - Dynamic range 

It's been forever since the last Ask Augustin! This is actually an episode that I filmed 5-6 weeks ago, about dynamic range, but that I finally had time to cut together.
Dynamic range is what makes classical music exciting - there is a general trend in many other genres to compress dynamics, so everything is as loud as possible all the time. But in classical music, the contrasts are everything!
It's easiest to play at medium volume, but the really soft and really loud dynamics are trickier and require quite a lot of practice. Dynamics are created entirely by the bow, and it's essential to understand the parameters that control dynamics (as well as sound colors): the relationship between bow pressure, bow speed and contact point (how close to the bridge or to the fingerboard you play), as well as how angled the bow is.
It's important to remember that dynamics are perceived relative to the space you're playing in and to who else is playing at the same time, so this context ultimately decides how soft or loud a pianissimo or a fortissimo should be played in any given setting. Even if you prepare your dynamics a certain way in practice, and it sounds ideal in a space you know, when you arrive in a concert hall or play with a chamber group or a piano or an orchestra, you might need to play softer or louder than you prepared and thus have to change how you use your bow a lot! Many of these adjustments have to be done on the spot, but with experience it becomes easier to get a sense of a hall quickly, based on the resonance that comes back to you. You can always ask a friend to listen in the hall, or go listen yourself while the orchestra is rehearsing a different piece.
If you record anything, always disable any option that sets the audio volume automatically - whether it's a camera, or software like Zoom - because it will make your soft and loud sounds the same volume and thus make you sound worse. This is essential if you send audition tapes - with volume compression it might sound as though you ignored all the dynamic markings in the score and many nuances will be lost!