A sampled drum sound can get pretty boring. There’s even a name for triggering the same sound repeatedly—“the machine gun effect.” Sometimes you want this, but often, it’s preferable to have a sound that responds to velocity and is more expressive.
There are two ways to address this with Impact XT, depending on whether you have multiple samples recorded at different intensities (i.e., softer and harder hits), or only one sample, which then means you have to “fake” it sounds like it was recorded with different intensities.
Multiple Drum Samples
This is the most common way to create expressive drum parts. Drum sample libraries often include multiple versions of the same drum sound—like soft, medium, and hard hits. The technique we’ll describe here works for more than three samples, but limiting it to three is helpful for the sake of illustration.
Impact XT makes it super-simple to take advantage of sounds recorded at different intensities because you can load multiple samples on a single pad. However, note that if a pad already contains a sample and you drag a new sample to a pad, it will replace, not supplement, the existing sample. So, you need to use a different approach.
Figure 1: Click on the + sign to load another sample on to a pad.
Figure 2: The splitter bar between samples can alter the velocity range to which a sample responds.
Now you’ll trigger different drum samples, depending on the velocity.
How to Fake Multiple Drum Samples
If you have a single drum sample with a hard hit, then you can use Impact XT’s sample start parameter to fake softer hits by changing the sample start time. (Starting sample playback later in the sample cuts off part of the attack, which sounds like a drum that’s hit softer.)
Figure 3: Click on the sample start line, and drag right to start sample playback past the initial attack. The readout toward the lower right shows the amount of offset, in samples.
Play the drum at different velocities. Tweak sample start times, and/or velocities, to obtain a smooth change from lower to higher velocities.
But Wait…There’s More!
Let’s add two more elements to emphasize the dynamics. These parameters affect all samples loaded on the pad, and are also effective with pads that have only a single sample.
Figure 4: Assigning velocity to Pitch and Filter Cutoff can enhance dynamics even further.
At the Pitch module, turn up the Velocity to Pitch parameter by around 0.26 semitones (Fig. 4). This raises the pitch slightly when you hit the drum harder, which emulates acoustic drums (the initial strike raises the tension on the head, which increases pitch slightly, depending on how hard you hit the drum).
Similarly, back off on the Filter Cutoff slightly, and turn up the Filter’s Vel parameter a little bit (e.g., 10%). This will make the sound brighter with higher velocities.
Done! Now go forth, and give your music more expressive drum sounds.