Spitfire instruments, by default, were designed to provide a crescendo attack when playing a sustain (or legato) note. The long articulations build slowly and take roughly a second or so to reach their full dynamic, giving you a swell that's great for beginning chords or melodies.
Sometimes, though, you need a bit of bite to your attack. A traditional method to achieve this with samples has been to overlay spiccato or staccato notes onto the beginnings of longs, but these can give mixed results. Since the introduction of the BML range, the legato and sustain string articulations in Spitfire instruments contain an alternative hard attack that is controlled via note velocity. Take a listen to the comparison between two notes below:
The second of each note contains the hard attack, trigger by playing the sustain with a high velocity (in this instance, all the way up at 127). In the Spitfire BML instrument range (and in future planned updates) these hard attacks are not simply overlaid short notes. They're actual recordings of a much stronger attack. For Sable Volume 1+3 owners, we'll also be adding an extra 'Marcato attack' to the sustain articulation in the upcoming update that provides an emphasised attack for the f dynamics and above. These are also based on separate recordings made especially for volume 3.
BML Mural (and the upcoming Sable 1.2 update) provides two ways to end a Sustain, Flautando, CS or Sul Pont note. The first is a traditional abrupt stop. This is the sound of the players instantly stopping the note with only the decay of the sound being heard in the hall. The second is a soft release. This is a much smoother transition from full-dynamics to silence via a decrescendo.
To select which type of release you want to use, Mural provides a Release slider on the Advanced Configuration panel (click to access it). The slider can be in one of two modes, off or on. When you depress a key with this slider set to off, releases are abrupt and quick. When releasing with it set to on, they're slow and smooth. Here's a comparison of the sound difference between each one:
Soft releases are great for playing chord progressions or 'pad' style phrases. The Release slider is controllable via CC17
in your DAW, though as with all controls this can be customised to your desired CC #.