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1. Using velocity as a modulation source

1 Aside from its obvious connection to volume, the other primary use of MIDI velocity data is as a modulation source in synths and samplers, and more often than not, the target of choice is the cutoff frequency of said instrument’s filter. Pretty much every soft synth and sampler lets you to make this most basic of assignments – here, we’re using Synapse Audio’s Dune 2. 2 The MIDI part triggering the synth jumps between velocity values, but our Dune 2 patch is set up in the Velocity page of its Settings panel so that it always outputs notes at full volume, regardless of velocity. We could also dial in filter modulation in the same panel, but most synths would require this to be done in a modulation matrix of some sort, so we’ll do that instead… 3 Making the relevant assignment in Dune 2’s Modulation Matrix is straightforward: we select Velocity as the source in the left-hand column and Filter Cutoff as the target in the right, then raise the Amount in the middle. The higher the Amount goes, the more profoundly the velocity level of each note influences the movement of the filter cutoff. 4 There are plenty of other ways in which velocity can be used to make radical changes to a synth sound from note to note, some of the most exciting working right down at the oscillator level. Xfer Records’ Serum is very well equipped in this regard thanks to its flexible wavetable oscillators, enabling velocity modulation of Wavetable Position and/or Warp amount, amongst other things. 5 If your synth features built-in effects – as Serum does with its impressive ten-strong rack – their parameters might well be available as modulation targets, too. Assigning Velocity to multiple effects controls, each with its own carefully set depth, can deliver spectacular results. 6 Velocity can even be used to modulate other modulators. Back in Dune 2’s mod matrix, we can assign it to three transformative LFO parameters: Amount, Rate and Initial Phase, each of which has a very different effect on the output of the LFO. Of course, there’s nothing stopping you applying different amounts of velocity modulation to all three at the same time. 7 The average sampler is also loaded with velocity modulation possibilities, opening it up to all sorts of audio playback and manipulation trickery. Despite its modest feature set, Ableton Live’s Impulse drum sampler is surprisingly capable in this area, with Velocity mod depth spinners housed under five of its main parameters. Let’s use them to mess with the hi-hats in a programmed drum loop… 8 First we’ll modulate the panning. Start by lowering the Velocity-to- Volume amount to 0, so that the hi-hat hits are all at the same volume, regardless of velocity – it would sound odd having volume follow pan position. Then, simply raise the Velocity-to- Pan spinner to hear the hats shift from left to right depending on their note velocity, with 1 being fully left and 127 fully right. 9 Even more fun than that is the Stretch parameter, which can be set to timestretch the triggered sample by velocity. Again, the assignment is already made – we just have to raise or lower the Velocity spinner under the Stretch control to have the sound progressively stretch or compress as the velocity increases. Of the two stretch modes, Mode B is the better suited to high-pitched sounds.