TECH TIP: Liven Up Your Electronic Drums
by Craig Anderton
In today’s rhythm-based music, there’s nothing worse than a dull drum pattern that doesn’t do what it’s supposed to do: Get people moving! Even if you come up with a good part, though, what about your sounds? Real drums have complex timbre changes that add excitement; if you want electronic drums to have the same kind of excitement, you need to create those timbral variations yourself.
Fortunately, today’s soft synths, samplers, and groove boxes have rich editing options. By tweaking a few parameters, you can create more expressive, powerful, and personalized sounds. Here are some of my favorite drum tweaks.
Pitch Shifting
Pitch control parameters are very useful. You can:
* Accommodate different musical styles. Some house music pitches drums lower, whereas drum ’n’ bass often pitches them up. You may not need a new set of samples – try retuning the ones you have.
* Create multiple drum sounds from one. Want to play a two-hand shaker part, but you have only one shaker sample? Copy it, then detune the copy by a semitone or so to provide a slight sonic variation. Detuning can also create a family of toms out of one tom sample.
* Tune drums to the song’s key, particularly with toms and resonant kick drums (such as the famously overused TR-808 "hum drum"). If the kick is out of tune with the bass, the sound can be muddy, and weaken the entire rhythm section. If fine tuning is not available as a control (sometimes you can change tuning only in semitones), you may be able to feed in a constant amount of pitch bend instead.
* Use radical transpositions to create new sounds. Most drum boxes don’t have a gong sound, but here’s how to create one. First, take your longest cymbal sound and detune it by 12 to 20 semitones. Create another version of the cymbal and detune it by about 3 semitones. Layer the two together; the slightly detuned cymbal gives a convincing attack, while the highly detuned one provides the necessary sustain.
* If your drum sound source can assign velocity to pitch modulation, you can increase dynamics by programming high velocity levels to add a very slight upward pitch shift. This works best if you apply velocity to the pitch envelope amount, then modulate the drum’s pitch from the envelope. This way, after attacking at a higher pitch, the drum will fall back to the normal pitch. A small increase emulates a drum’s skin being stretched, hence pitched higher, when it’s first hit.
Changing the Sample Start Point
Altering a sample’s start point under velocity control can add convincing dynamics.
Most drum machines won’t do this, but many synths and samplers will. Generally, you set the initial sample start point several tens, or even hundreds, of milliseconds "late" into the sample so it’s past where the attack occurs. Now assign negative velocity to modulate the sample start point. At low velocities, you don’t hear the signal’s initial attack; higher velocities kick the sample point further toward the beginning, until at maximum velocity you hear the entire attack.
If you already have a good MIDI drum part but it lacks dynamics, you can add sample start modulation after recording. Overdub a controller track using a mod wheel or MIDI fader, and assign the controller to sample start time.
Filter Modulation
For additional dynamic control, assign velocity to filter cutoff so that hitting the drum harder produces a slightly brighter sound. This gives extra emphasis to the hardest hits, making the drums feel more "alive." Soft taps will sound a bit muted.
Hi-Hat Amplitude Envelope Decay Modulation
One of the most annoying "features" of electronic drums is the hi-hat. A real drummer is constantly working the hi-hat, opening and closing it with the pedal, but the electronic version is an unchanging snapshot. Sure, you can program a combination of open, half-closed, and closed hi-hat notes, and assign them to a mute group (see below) so each will cut off the others, but programming a rhythm with three hat sounds is boring, and doesn’t always sound that realistic.
A more expressive option is to use a MIDI controller, such as mod wheel, to vary an open hi-hat sound’s envelope decay time. Close the decay for a closed hi-hat; as you increase the decay, the hi-hat opens gradually. I usually play the hi-hat note with my right hand and move the mod wheel with my left, but this is also an operation that lends itself well to "post-processing" – record the part, then overdub the controller changes necessary to create a more expressive track.
Overdrive
Most drums have a quick initial attack, followed by an abrupt decay. Adding a little bit of overdrive distortion will "crunch" the attack’s first few milliseconds, while leaving the decay untouched. You can do this with an overdrive or distortion plug-in, or modify the sample itself using a digital audio editor, then loading it into the drum module.
This affects the sound in three important ways:
* You can raise the overall average level of the drum for a louder perceived sound, because the overdrive effect will limit the percussive attack. This is like using a dynamic range limiter.
* It creates a short period of time where the sound is at its maximum level, thus contributing a feeling of "punch."
* It increases the attack’s harmonic content, producing a brighter attack.
Mute Groups
When drums are assigned to a mute group, hitting a drum that’s part of the group will cut off any other drum from the group that’s still sounding. This is mostly intended for hi-hats, so that playing a closed hi-hat sound will shut off an open hi-hat. But there are other uses for mute groups:
* Assign toms with long decays to the same mute group. Too many simultaneous tom decays can muddy up a track. When you assign them to the same mute group, not only do tom rolls sound cleaner, but you conserve polyphony.
* If you have some rhythmic loops loaded into your sampler along with individual drum sounds, make the loops part of a mute group (assuming, of course, you don’t plan to layer them). This is particularly important if you’re playing live. Suppose you have a bunch of four-measure loops, but you’re hitting a build and you want to switch quickly between the first measure, or first two measures, of various loops. Assigning loops to the same mute group means you can start them whenever you like, knowing that the other ones will shut up when you do.
Single-Cycle Looping
This sampling-oriented trick can turn a quick hit into one with a loooooooong decay, particularly with toms and kicks.
Loop a single cycle in the drum’s decay tail so it repeats indefinitely. Then, apply an amplitude envelope to give the decay the desired length. Try different individual cycles for looping; they may appear almost identical in the waveform display, but some will usually loop better than others, and the harmonic content may differ as well. Also try adding some pitch shift to the decay so it goes lower in pitch as it decays.
Click Layering
Sometimes modulating an existing sample just isn’t enough to create serious dynamics. This is where a click sample or sound can come in handy.
For samplers, create a click sample. I made mine by simply drawing some spikes in a digital audio editor for about 35ms, and saved that as a file. With synthesized drums, you can make a good click by applying maximum, extremely short pitch modulation to a white noise source or buzzy oscillator, then impose a very quick amplitude decay.
The goal is to layer the click with another sound, such as kick. But choose a velocity curve where the click is very quiet at lower velocity levels, so that the click appears only in the upper dynamic range of the sound with which it is layered. As you play harder, the click will become more audible, adding punch to the drum sound. A little lowpass filtering on the click will help blend the two sounds to taste.
Remember, machines don’t make dull music – people do. If you want your drum parts to really grab your listeners, use some of these tricks to help your sounds come alive.
