What is the relationship between velocity, dynamics, and expression in the Spitfire Libraries?

I just watched Paul Thompson's excellent YouTube tutorial on velocities, published in Aug 2021. However, most non-piano Spitfire libraries seem to use dynamics and expression instead. What is the relationship?


  • The role of velocity and dynamics will vary depending on what instrument and what articulation you are using. Expression (CC11) is basically a 'volume' control.

    Let's use a staccato violin as our first example. Velocity will determine the dynamic layer (how aggressively the note is played/struck). Lower velocity gives a gentler attack, which will also naturally produce a little less volume. The higher velocity gives a stronger attack, naturally producing more volume.

    Now, let's use legato violin as our next example. Dynamics (CC1) will determine which dynamic layer is being played. At first, it can just seem like another 'volume' control, but it really does more than that. There are distinct personalities of different dynamic layers that can't be achieved by volume adjustments alone. Velocity will affect how the legato notes transition to the next note, whether portamento, slur, detache, etc.

    I do hope this helps. Experiment with all of these parameters, and have fun!